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1.
J Neuroinflammation ; 20(1): 295, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-38082296

RESUMEN

The role of high mobility group box 1 (HMGB1) in inflammation is well characterized in the immune system and in response to tissue injury. More recently, HMGB1 was also shown to initiate an "inflammatory signaling cascade" in the brain parenchyma after a mild and brief disturbance, such as cortical spreading depolarization (CSD), leading to headache. Despite substantial evidence implying a role for inflammatory signaling in prevalent neuropsychiatric disorders such as migraine and depression, how HMGB1 is released from healthy neurons and how inflammatory signaling is initiated in the absence of apparent cell injury are not well characterized. We triggered a single cortical spreading depolarization by optogenetic stimulation or pinprick in naïve Swiss albino or transgenic Thy1-ChR2-YFP and hGFAP-GFP adult mice. We evaluated HMGB1 release in brain tissue sections prepared from these mice by immunofluorescent labeling and immunoelectron microscopy. EzColocalization and Costes thresholding algorithms were used to assess the colocalization of small extracellular vesicles (sEVs) carrying HMGB1 with astrocyte or microglia processes. sEVs were also isolated from the brain after CSD, and neuron-derived sEVs were captured by CD171 (L1CAM). sEVs were characterized with flow cytometry, scanning electron microscopy, nanoparticle tracking analysis, and Western blotting. We found that HMGB1 is released mainly within sEVs from the soma of stressed neurons, which are taken up by surrounding astrocyte processes. This creates conditions for selective communication between neurons and astrocytes bypassing microglia, as evidenced by activation of the proinflammatory transcription factor NF-ĸB p65 in astrocytes but not in microglia. Transmission immunoelectron microscopy data illustrated that HMGB1 was incorporated into sEVs through endosomal mechanisms. In conclusion, proinflammatory mediators released within sEVs can induce cell-specific inflammatory signaling in the brain without activating transmembrane receptors on other cells and causing overt inflammation.


Asunto(s)
Astrocitos , Proteína HMGB1 , Animales , Ratones , Astrocitos/metabolismo , Proteína HMGB1/metabolismo , Inflamación/etiología , Neuronas/metabolismo , Transducción de Señal
2.
Eur J Obstet Gynecol Reprod Biol ; 287: 36-45, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37276727

RESUMEN

BACKGROUND: Despite its routine and frequent application, cryopreservation of human sperm is far from the desired efficacy, as freezing and thawing impair motility, viability, acrosomal unity, and DNA integrity. OBJECTIVES: In this study, the authors aimed to investigate whether adding antioxidants, coenzyme Q10, and curcumin into the freezing medium provide better efficacy in the cryopreservation of human sperm. METHODS: The semen samples from 40 healthy men aged 18-45 were collected in sterile containers by masturbation. Samples within normal reference values for sperm concentration (≥15 million/mL) and motility (progressive motile ≥ 32% and total motility ≥ 40%) were included in the study. Semen samples were equally divided into five groups and evaluated; i) pre-freezing sperm suspension, ii) frozen-thawed control (Ctrl) without any supplementation in freezing medium, iii) frozen-thawed with curcumin supplementation of 0.25 mM (Cur), iv) frozen-thawed coenzyme Q10 supplementation of 25 µM (CoQ10) and v) frozen-thawed curcumin (0.25 mM) plus coenzyme Q10 (25 µM) supplementation (CurCoQ10) into the freezing medium. Liquid nitrogen vapour freezing and rapid thawing were performed in each group (ii-v). Sperm motility, viability, acrosome integrity, and DNA fragmentation rates were compared and ultrastructural evaluations by transmission electron microscopy were undertaken between the groups. Additionally, the total antioxidant capacity/total oxidant capacity values were measured. RESULTS: According to CASA results, progressive motility was significantly higher in the CoQ10 group (9.4 ± 7.6) when compared with the Ctrl (7.1 ± 6.3), Cur (6.4 ± 4.8) and CurCoQ10 (8.1 ± 7.7) groups (p < 0.05). Flow cytometry results showed no difference in the viability and acrosome integrity values after thawing, but DNA fragmentation was significantly increased in the curcumin-added groups (p < 0.05). Acrosomal changes and sub-acrosomal defects were seen in all groups after thawing at the ultrastructural level. Mitochondrial membrane structure was preserved in CoQ10 and CurCoQ10 groups. CONCLUSIONS: Our results suggested that sperm ultrastructural morphology and motility were better preserved in the CoQ10 group during cryopreservation. In curcumin groups, DNA fragmentation and head defects were increased.


Asunto(s)
Curcumina , Preservación de Semen , Humanos , Masculino , Congelación , Curcumina/farmacología , Semen , Motilidad Espermática , Preservación de Semen/métodos , Criopreservación/métodos , Espermatozoides , Antioxidantes/farmacología , Suplementos Dietéticos
3.
J Knee Surg ; 35(2): 222-230, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33930897

RESUMEN

Cell-free scaffolds used in cartilage regeneration are produced from different materials. The aim of this study is to compare the clinical and radiological results of two different scaffolds with hyaluronan- or chitosan-based structure used in the treatment of symptomatic condylar osteochondral lesions. The study comprises 69 patients who were operated for osteochondral lesion repair with hyaluronan- (n = 37) or chitosan-based (n = 32) scaffold. The International Knee Documentation Committee (IKDC), Lysholm Knee Scoring Scale and Visual Analog Scale (VAS) scores were collected for both groups at the preoperative and postoperative 3rd, 12th, and 24th months. Magnetic resonance imaging was performed between the 12th and 15th months postoperatively and this with magnetic resonance observation of cartilage repair tissue (MOCART) scoring were compared. Within group assessments demonstrate significant improvement in IKDC, Lysholm, and VAS scores at postoperative 3rd and 12th months. However, in both groups, IKDC, Lysholm and, VAS scores at the postoperative 24th month indicate no significant further improvement, compared with the 12th month results. There was no significant difference between the groups in terms of IKDC, Lysholm, VAS, and MOCART scores at any time period. This study shows that both scaffolds are useful in cartilage regeneration but have no clinical or radiological superiority to each other. Surgeons should select the method with which they feel comfortable. This is a level III, retrospective comparative study.


Asunto(s)
Cartílago Articular , Quitosano , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/cirugía , Estudios de Seguimiento , Humanos , Ácido Hialurónico , Articulación de la Rodilla , Imagen por Resonancia Magnética , Estudios Retrospectivos , Andamios del Tejido , Resultado del Tratamiento
4.
Cardiovasc Ther ; 2021: 5516185, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34737791

RESUMEN

OBJECTIVES: Transcriptomics of atrial fibrillation (AFib) in the setting of chronic primary mitral regurgitation (MR) remains to be characterized. We aimed to compare the gene expression profiles of patients with degenerative MR in AFib and sinus rhythm (SR) for a clearer picture of AFib pathophysiology. METHODS: After transcriptomic analysis and bioinformatics (n = 59), differentially expressed genes were defined using 1.5-fold change as the threshold. Additionally, independent datasets from GEO were included as meta-analyses. RESULTS: QRT-PCR analysis confirmed that AFib persistence was associated with increased expression molecular changes underlying a transition to heart failure (NPPB, P = 0.002; ANGPTL2, P = 0.002; IGFBP2, P = 0.010), structural remodeling including changes in the extracellular matrix and cellular stress response (COLQ, P = 0.003; COMP, P = 0.028; DHRS9, P = 0.038; CHGB, P = 0.038), and cellular stress response (DNAJA4, P = 0.038). Furthermore, AFib persistence was associated with decreased expression of the targets of structural remodeling (BMP7, P = 0.021) and electrical remodeling (CACNB2, P = 0.035; MCOLN3, P = 0.035) in both left and right atrial samples. The transmission electron microscopic analysis confirmed ultrastructural atrial remodeling and autophagy in human AFib atrial samples. CONCLUSIONS: Atrial cardiomyocyte remodeling in persistent AFib is closely linked to alterations in gene expression profiles compared to SR in patients with primary MR. Study findings may lead to novel therapeutic targets. This trial is registered with ClinicalTrials.gov identifier: NCT00970034.


Asunto(s)
Apéndice Atrial , Fibrilación Atrial , Remodelación Atrial , Insuficiencia de la Válvula Mitral , Canales de Potencial de Receptor Transitorio , Proteína 2 Similar a la Angiopoyetina , Proteínas Similares a la Angiopoyetina , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/genética , Atrios Cardíacos , Humanos , Insuficiencia de la Válvula Mitral/genética
5.
J Int Med Res ; 49(9): 3000605211044382, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34521239

RESUMEN

Coronavirus disease 2019 (COVID-19) following infection by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has caused a global pandemic that is still having serious effects worldwide. This virus, which targets the lungs in particular, can also damage other tissues. Angiotensin converting enzyme 2 (ACE-2) plays a key role in viral entry into host cells. The presence of ACE-2 in various tissues may permit viral infection. Studies of COVID-19 often make use of postmortem tissues. Although this information provides various useful results, it is also necessary to conduct in vitro studies to understand optimal treatment approaches. Because the virus may show species-specific differences, in vitro technologies using human cells are particularly important. Organoid technologies, three-dimensional structures that can be obtained from human cells, are playing increasingly important roles in studies of SARS-CoV-2. This technology offers a significant advantage in terms of mimicking in vivo tissue structures and testing antiviral compounds. In this mini-review, we summarize studies of SARS-CoV-2 using both histopathological and organoid technology approaches.


Asunto(s)
COVID-19 , Humanos , Organoides , Pandemias , Peptidil-Dipeptidasa A , SARS-CoV-2 , Tecnología
6.
Andrologia ; 52(7): e13636, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32453883

RESUMEN

Blood-testis barrier (BTB) is critical for maintaining fertility. The integrity of tight junctions (TJs) provides restricted permeability of BTB. The aim of this study was to evaluate the relationship between BTB and Sertoli cells. Testicular sperm extraction (TESE) obtained from nonobstructive azoospermia (NOA) patients was examined: Group I (spermatozoa+) and Group II (spermatozoa-). The tissues were stained with haematoxylin eosin, periodic acid-Schiff and Masson's trichrome for Johnsen's score evaluation. Apoptosis and adhesion molecules such as claudin-11, occludin and ZO-1 were assessed. In Group I, the integrity of the seminiferous tubules was intact. In Group II, some seminiferous tubule walls were lined only with Sertoli cells, had a thickening of the basement membrane, and oedema in interstitial spaces. In Group I, the seminiferous tubule consisted of a stratified columnar epithelium, claudin-11 expressions were observed as linear staining in the basal zone of the tubule, while seminiferous tubules, with low epithelium, displayed a punctate type of staining. Immunohistochemical observations were consistent with the ultrastructural findings. In Group II, high apoptosis and unstained/irregular TJ formation in claudin-11, occludin and ZO-1 were observed. In conclusion, disruption of relation between BTB and TJs may reveal inadequate spermatogenesis, which is one of the mechanisms behind azoospermia.


Asunto(s)
Azoospermia , Barrera Hematotesticular , Humanos , Masculino , Túbulos Seminíferos , Células de Sertoli , Espermatogénesis , Uniones Estrechas
7.
Sci Rep ; 8(1): 14770, 2018 10 03.
Artículo en Inglés | MEDLINE | ID: mdl-30282977

RESUMEN

The initial phase of neuronal death is not well characterized. Here, we show that expansion of the nuclear membrane without losing its integrity along with peripheralization of chromatin are immediate signs of neuronal injury. Importantly, these changes can be identified with commonly used nuclear stains and used as markers of poor perfusion-fixation. Although frozen sections are widely used, no markers are available to ensure that the observed changes were not confounded by perfusion-induced hypoxia/ischemia. Moreover, HMGB1 was immediately released and p53 translocated to mitochondria in hypoxic/ischemic neurons, whereas nuclear pore complex inhibitors prevented the nuclear changes, identifying novel neuroprotection targets.


Asunto(s)
Encéfalo/ultraestructura , Hipoxia-Isquemia Encefálica/genética , Neuronas/ultraestructura , Membrana Nuclear/ultraestructura , Animales , Animales Recién Nacidos , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Muerte Celular/genética , Núcleo Celular/genética , Núcleo Celular/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/ultraestructura , Cromatina/genética , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/ultraestructura , Modelos Animales de Enfermedad , Glucosa/genética , Proteína HMGB1/genética , Humanos , Hipoxia-Isquemia Encefálica/patología , Ratones , Microscopía Electrónica de Rastreo , Mitocondrias/genética , Mitocondrias/patología , Mitocondrias/ultraestructura , Neuronas/patología , Membrana Nuclear/patología , Fijación del Tejido/normas
8.
Turk J Haematol ; 35(4): 229-259, 2018 11 13.
Artículo en Inglés | MEDLINE | ID: mdl-30040071

RESUMEN

Objective: To examine granulocytic and non-granulocytic cells in children with severe congenital neutropenia (SCN) and their non-neutropenic parents. Materials and Methods: Fifteen patients with SCN and 21 non-neutropenic parents were evaluated for a) CD95, CD95 ligand, annexin V, propidium iodide, cell cycle, and lymphocyte subsets by flow cytometry; b) rapid cell senescence (of leukocytes) by senescence-associated ß-galactosidase stain; c) aggregation tests by aggregometer; d) in vitro bleeding time by PFA-100 instrument; e) mepacrine-labeled dense granule number of thrombocytes by fluorescence microscope; and f) hematomorphology by light and electron microscope. HAX1, ELANE, G6PC3, CSF3R, and JAGN1 mutations associated with SCN were studied in patients and several parents. Results: Significant increase in apoptosis and secondary necrosis in monocytes, lymphocytes, and granulocytes of the patients and parents was detected, irrespective of the mutation type. CD95 and CD95 ligand results implied that apoptosis was non-CD95-mediated. Leukocytes of 25%, 12.5%, and 0% of patients, parents, and controls showed rapid cell senescence. The cell cycle analysis testable in four cases showed G1 arrest and apoptosis in lymphocytes of three. The patients had HAX1 (n=6), ELANE (n=2), G6PC3 (n=2), and unidentified (n=5) mutations. The CD3, CD4, and NK lymphocytes were below normal levels in 16.6%, 8.3%, and 36.4% of the patients and in 0%, 0%, and 15.4% of the parents (controls: 0%, 0%, 5.6%). The thrombocytes aggregated at low rates, dense granule number/thrombocyte ratio was low, and in vitro bleeding time was prolonged in 37.5%-66.6% of patients and 33.3%-63.2% of parents (vs. 0% in controls). Under electron and/or light microscope, the neutrophils, monocytes, lymphocytes, and thrombocytes in the peripheral blood of both patients and parents were dysplastic and the bone marrow of patients revealed increased phagocytic activity, dysmegakaryopoiesis, and necrotic and apoptotic cells. Ultrastructurally, thrombocyte adhesion, aggregation, and release were inadequate. Conclusion: In cases of SCN, patients' pluripotent hematopoietic stem cells and their non-neutropenic parents are both affected irrespective of the genetic defect.


Asunto(s)
Granulocitos/patología , Linfocitos/patología , Neutropenia/congénito , Neutrófilos/patología , Adolescente , Adulto , Muerte Celular , Niño , Preescolar , Síndromes Congénitos de Insuficiencia de la Médula Ósea , Femenino , Granulocitos/metabolismo , Humanos , Lactante , Linfocitos/metabolismo , Masculino , Persona de Mediana Edad , Neutropenia/metabolismo , Neutropenia/patología , Neutrófilos/metabolismo , Adulto Joven
9.
Arch Med Sci ; 14(2): 381-387, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29593813

RESUMEN

INTRODUCTION: Bisphosphonates are widely used in metastatic cancer such as prostate and breast cancer, and their nephrotoxic effects have been established previously. In this study we aimed to evaluate both the nephrotoxic effects of zoledronic acid (ZA) and the protective effects of vitamin E (Vit-E) on this process under light and electron microscopy. MATERIAL AND METHODS: A total of 30 male Sprague-Dawley rats were divided into 3 groups. The first group constituted the control group. The second group was given i.v. ZA of 3 mg/kg once every 3 weeks for 12 weeks from the tail vein. The third group received the same dosage of ZA with an additional i.m. injection of 15 mg Vit-E every week for 12 weeks. Tissues were taken 4 days after the last dose of ZA for histopathological and ultrastructural evaluation. Paller score, tubular epithelial thickness and basal membrane thickness were calculated for each group. RESULTS: For group 2, the p-values are all < 0.001 for Paller score, epitelial thickness, and basal membrane thickness. For group 3 (ZA + Vit. E), the p-values are < 0.001 for Paller score, 0.996 for epitelial thickness, and < 0.001 basal membrane thickness. Significant differences were also observed in ultrastructural changes for group 2. However, adding Vit-E to ZA administration reversed all the histopathological changes to some degree, with statistical significance. CONCLUSIONS: Administration of ZA had nephrotoxic effects on rat kidney observed under both light and electron microscopy. Concomitant administration of Vit-E significantly reduces toxic histopathological effects of ZA.

10.
Exp Neurol ; 299(Pt A): 26-41, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28974375

RESUMEN

Tay-Sachs disease is a severe lysosomal storage disorder caused by mutations in Hexa, the gene that encodes for the α subunit of lysosomal ß-hexosaminidase A (HEXA), which converts GM2 to GM3 ganglioside. Unexpectedly, Hexa-/- mice have a normal lifespan and show no obvious neurological impairment until at least one year of age. These mice catabolize stored GM2 ganglioside using sialidase(s) to remove sialic acid and form the glycolipid GA2, which is further processed by ß-hexosaminidase B. Therefore, the presence of the sialidase (s) allows the consequences of the Hexa defect to be bypassed. To determine if the sialidase NEU3 contributes to GM2 ganglioside degradation, we generated a mouse model with combined deficiencies of HEXA and NEU3. The Hexa-/-Neu3-/- mice were healthy at birth, but died at 1.5 to 4.5months of age. Thin-layer chromatography and mass spectrometric analysis of the brains of Hexa-/-Neu3-/- mice revealed the abnormal accumulation of GM2 ganglioside. Histological and immunohistochemical analysis demonstrated cytoplasmic vacuolation in the neurons. Electron microscopic examination of the brain, kidneys and testes revealed pleomorphic inclusions of many small vesicles and complex lamellar structures. The Hexa-/-Neu3-/- mice exhibited progressive neurodegeneration with neuronal loss, Purkinje cell depletion, and astrogliosis. Slow movement, ataxia, and tremors were the prominent neurological abnormalities observed in these mice. Furthermore, radiographs revealed abnormalities in the skeletal bones of the Hexa-/-Neu3-/- mice. Thus, the Hexa-/-Neu3-/- mice mimic the neuropathological and clinical abnormalities of the classical early-onset Tay-Sachs patients, and provide a suitable model for the future pre-clinical testing of potential treatments for this condition.


Asunto(s)
Gangliosidosis GM2/genética , Hexosaminidasa B/genética , Neuraminidasa/genética , Enfermedad de Tay-Sachs/genética , Animales , Química Encefálica/genética , Vesículas Citoplasmáticas/patología , Gangliosidosis GM2/metabolismo , Gliosis/genética , Gliosis/patología , Glicoesfingolípidos/metabolismo , Cojera Animal/genética , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuraminidasa/deficiencia , Neuronas/patología , Células de Purkinje/patología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Enfermedad de Tay-Sachs/patología
11.
Cell Tissue Bank ; 19(1): 133-147, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29039070

RESUMEN

In this study, the efficiency of the "Needle Immersed Vitrification" technique was tested on cryopreserved feline ovarian tissue. For vitrification, ovarian fragments (0.5-1.5 mm2) from each ovary were collected; the grafts were exposed to 7.5-15% ethylene glycol and 7.5-15% dimethyl sulfoxide at room temperature and stored in liquid nitrogen at least 1 week. Morphologic examinations, expression of genes such as B cell lymphoma 2, B-cell lymphoma-2-associated X protein, Bone morphogenetic protein 15, zone of polarizing activity, zona pellucida C protein and DNA (cytosine-5)-methyltransferase 1, ultrastructural analysis and viability tests were carried out from collected grafts. Light microscopy examinations revealed the percentage of morphologically normal primordial follicles in a fresh group which was significantly higher than the treatment groups (p < 0.001). Terminal deoxynucleotidyl transferase dUTP nick end labeling and anti-caspase-3 staining observed in oocytes, follicle cells, interstitial tissue showed higher rates of apoptosis for post-vitrification and -transplantation groups than freshly grafted ovarian tissues. Furthermore, we observed significant downregulation of zone of polarizing activity and zona pellucida C protein gene expression in vitrified ovarian tissue grafts than in the fresh grafts (p < 0.05). In conclusion, we suggest that the needle immersed vitrification method is a convenient, cheap, and feasible vitrification method for cat ovarian tissues. However, further studies need to be performed to determine more optimal vitrification solutions and equilibration times for the needle immersed vitrification method in order to adapt it for cat ovaries.


Asunto(s)
Criopreservación/veterinaria , Ovario/trasplante , Trasplante Heterólogo/veterinaria , Vitrificación , Animales , Apoptosis , Gatos , Supervivencia Celular , Criopreservación/métodos , Femenino , Masculino , Ratones , Ratones Desnudos , Ovario/citología , Ovario/ultraestructura , Trasplante Heterólogo/métodos
12.
J Tissue Eng ; 8: 2041731417697500, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28694960

RESUMEN

Cartilage defects are a source of pain, immobility, and reduced quality of life for patients who have acquired these defects through injury, wear, or disease. The avascular nature of cartilage tissue adds to the complexity of cartilage tissue repair or regeneration efforts. The known limitations of using autografts, allografts, or xenografts further add to this complexity. Autologous chondrocyte implantation or matrix-assisted chondrocyte implantation techniques attempt to introduce cultured cartilage cells to defect areas in the patient, but clinical success with these are impeded by the avascularity of cartilage tissue. Biodegradable, synthetic scaffolds capable of supporting local cells and overcoming the issue of poor vascularization would bypass the issues of current cartilage treatment options. In this study, we propose a biodegradable, tri-layered (poly(glycolic acid) mesh/poly(l-lactic acid)-colorant tidemark layer/collagen Type I and ceramic microparticle-coated poly(l-lactic acid)-poly(ϵ-caprolactone) monolith) osteochondral plug indicated for the repair of cartilage defects. The porous plug allows the continual transport of bone marrow constituents from the subchondral layer to the cartilage defect site for a more effective repair of the area. Assessment of the in vivo performance of the implant was conducted in an ovine model (n = 13). In addition to a control group (no implant), one group received the implant alone (Group A), while another group was supplemented with hyaluronic acid (0.8 mL at 10 mg/mL solution; Group B). Analyses performed on specimens from the in vivo study revealed that the implant achieves cartilage formation within 6 months. No adverse tissue reactions or other complications were reported. Our findings indicate that the porous biocompatible implant seems to be a promising treatment option for the cartilage repair.

13.
Zygote ; 25(3): 358-375, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28669362

RESUMEN

According to classical knowledge of reproductive biology, in the ovary of female mammals there is a limited number of oocytes and there is no possibility of renewal if the oocytes are lost due to disease or injury. However, in recent years, the results of some studies on renewal and formation of oocytes and follicles in the adult mammalian ovary have led to the questioning of this opinion. The aim of our study is to demonstrate the presence of putative germline and pluripotent stem cells in the adult mouse ovary and their differentiation potential into germ and somatic cells. In ovary tissues and cells harvested from pre-differentiation step, the expression of pluripotent and germline stem cell markers was analysed by reverse transcription-polymerase chain reaction (RT-PCR), immunofluorescence staining and western blotting. Embryoid bodies that formed in this step were analysed using immunofluorescence staining and transmission electron microscopy. Ovarian stem cells were induced to differentiate into oocyte, osteoblast, chondrocyte and neural cells. Besides morphological observation, differentiated cells were analysed by RT-PCR, histochemical and immunofluorescence staining. Expression of germline and pluripotent stem cell markers both in mRNA and at the protein level were detected in the pre-differentiated cells and ovary tissues. As a result of the differentiation process, the formation of oocyte-like cells, osteoblasts, chondrocytes and neural cells was observed and characteristics of differentiated cells were confirmed using the methods mentioned above. Our study results revealed that the adult mouse ovary contains germline and pluripotent stem cells with the capacity to differentiate into oocyte-like cells, osteoblasts, chondrocytes and neural cells.


Asunto(s)
Diferenciación Celular/fisiología , Oocitos/citología , Ovario/citología , Células Madre Pluripotentes/citología , Animales , Biomarcadores/metabolismo , Células Cultivadas , Condrocitos/citología , Femenino , Expresión Génica , Marcadores Genéticos , Ratones Endogámicos BALB C , Oocitos/fisiología , Osteoblastos/citología , Células Madre Pluripotentes/fisiología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
15.
Reprod Fertil Dev ; 27(7): 1020-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24647037

RESUMEN

There are many reasons, including cancer therapy, for premature ovarian failure and infertility. Oocyte, embryo and ovarian cryopreservation are current options for fertility preservation. Ovarian tissue cryopreservation is essential in patients whose cancer therapy cannot be delayed, including prepubertal girls, and is mostly performed using slow freezing. In the present study, mouse ovarian tissues were vitrified on copper electron microscope grids (n=18) or conventionally slow frozen (n=18). Post-thaw tissues were examined histologically using light and electron microscopy and compared with the control group. According to light microscopy observations, antral follicles were found to be better preserved with the slow freezing technique rather than vitrification. Electron microscopy revealed swollen mitochondria in the oocyte cytoplasm, condensations in the zona pellucida, breakages in the junctions of granulosa cells and vacuolisation in the extracellular space in pathologic follicles, which were relatively more frequent, in the vitrification group after thawing. These results indicate that ovarian slow freezing is preferable than vitrification on copper electron microscope grids, especially for larger follicles. Conversely, vitrification of ovarian pieces using cooper grids is user-friendly and provided good protection for primordial follicles and stromal cells. There is a need for further studies into advanced tissue vitrification techniques and carriers.


Asunto(s)
Criopreservación/métodos , Preservación de la Fertilidad/métodos , Ovario/ultraestructura , Vitrificación , Animales , Cobre , Crioprotectores , Femenino , Ratones
16.
Zygote ; 23(3): 315-26, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24355650

RESUMEN

For decades, scientists have considered that female mammals are born with a lifetime reserve of oocytes in the ovary, irrevocably fated to decline after birth. However, controversy in the matter of the possible presence of oocytes and granulosa cells that originate from stem cells in the adult mammalian ovaries has been expanded. The restricted supply of oocytes in adult female mammals has been disputed in recent years by supporters of neo-oogenesis, who claim that germline stem cells (GSCs) exist in the ovarian surface epithelium (OSE) or the bone marrow (BM). Differentiation of ovarian stem cells (OSCs) into oocytes, fibroblast-like cells, granulosa phenotype, neural and mesenchymal type cells and generation of germ cells from OSCs under the contribution of an OSC niche that consists of immune system-related cells and hormonal signalling has been claimed. Although these arguments have met with intense suspicion, their confirmation would necessitate the revision of the current classic knowledge of female reproductive biology.


Asunto(s)
Oogénesis/fisiología , Ovario/citología , Ovario/fisiología , Animales , Femenino , Humanos , Mamíferos , Oocitos , Células Madre/fisiología
17.
J Pediatr Hematol Oncol ; 36(4): 281-92, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-23887025

RESUMEN

Iron overload in hereditary hemochromatosis and hematologic malignancy has unfavorable effects on morbidity. Herein, 53 children (age 108.4±58.3 mo, 25 girls and 28 boys) with acute myeloblastic and lymphoblastic leukemia, who received 4 different chemotherapy protocols, were evaluated for iron overload throughout chemotherapy. Iron overload arose: (1) before chemotherapy, which was dependent on neither chemotherapy nor packed red blood cell transfusions and (2) after chemotherapy, which was dependent on the duration and nature of chemotherapy and partially on transfusion of packed red blood cells. Iron overload was documented in 75% of patients with a ferritin level >1000 ng/mL, by liver and heart magnetic resonance imaging, and they were administered iron-chelation therapy with success. Three of 10 radiologically iron-overloaded patients were heterozygous for H63D mutation. Aminolevulinic acid and porphobilinogen levels were normal. Light microscopic examination of the bone marrow revealed increased iron granules in erythroblasts, platelets, and megakaryocytes, iron-laden macrophages, free iron in the matrix, dyshematopoiesis, and apoptotic cells. Electron microscopic examination revealed iron-laden secondary lysosomes and autolysosomes in normoblasts and iron-laden primary granules in promyelocytes, irrelevant to the ferritin level, implying autophagia due to chemotherapy as a source of the excess iron. We think that iron overload, which is an important complication of acute leukemia, should be evaluated separately from "transfusion overload," and the management principles specific to leukemia should be implemented.


Asunto(s)
Células de la Médula Ósea , Médula Ósea , Hemocromatosis , Quelantes del Hierro/administración & dosificación , Leucemia Mieloide Aguda , Leucemia-Linfoma Linfoblástico de Células Precursoras , Adolescente , Ácido Aminolevulínico/sangre , Médula Ósea/metabolismo , Médula Ósea/ultraestructura , Células de la Médula Ósea/metabolismo , Células de la Médula Ósea/ultraestructura , Niño , Femenino , Ferritinas/sangre , Hemocromatosis/sangre , Hemocromatosis/complicaciones , Hemocromatosis/tratamiento farmacológico , Hemocromatosis/genética , Hemocromatosis/patología , Humanos , Hierro/sangre , Quelantes del Hierro/efectos adversos , Leucemia Mieloide Aguda/sangre , Leucemia Mieloide Aguda/tratamiento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/patología , Lisosomas/metabolismo , Lisosomas/ultraestructura , Masculino , Mutación Missense , Porfobilinógeno/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras/patología
18.
Bosn J Basic Med Sci ; 13(4): 218-24, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24289756

RESUMEN

Liver ischemia reperfusion injury (IRI) is an important pathologic process leading to bodily systemic effects and liver injury. Our study aimed to investigate the protective effects of diosmin, a phlebotrophic drug with antioxidant and anti-inflammatory effects, in a liver IRI model. Forty rats were divided into 4 groups. Sham group, control group (ischemia-reperfusion), intraoperative treatment group, and preoperative treatment group. Ischemia reperfusion model was formed by clamping hepatic pedicle for a 60 minute of ischemia followed by liver reperfusion for another 90 minutes. Superoxide dismutase (SOD) and catalase (CAT) were measured as antioaxidant enzymes in the liver tissues, and malondialdehyde (MDA) as oxidative stress marker, xanthine oxidase (XO) as an oxidant enzyme and glutathione peroxidase (GSH-Px) as antioaxidant enzyme were measured in the liver tissues and the plasma samples. Hepatic function tests were lower in treatment groups than control group (p<0.001 for ALT and AST). Plasma XO and MDA levels were lower in treatment groups than control group, but plasma GSH-Px levels were higher (p<0.05 for all). Tissue MDA levels were lower in treatment groups than control group, but tissue GSH-Px, SOD, CAT and XO levels were higher (p<0.05 for MDA and p<0.001 for others). Samples in control group histopathologically showed morphologic abnormalities specific to ischemia reperfusion. It has been found that both preoperative and intraoperative diosmin treatment decreases cellular damage and protects cells from toxic effects in liver IRI. As a conclusion, diosmin may be used as a protective agent against IRI in elective and emergent liver surgical operations.


Asunto(s)
Diosmina/farmacología , Hígado/efectos de los fármacos , Hígado/lesiones , Daño por Reperfusión/prevención & control , Alanina Transaminasa/metabolismo , Animales , Antioxidantes/metabolismo , Antioxidantes/farmacología , Aspartato Aminotransferasas/metabolismo , Catalasa/metabolismo , Modelos Animales de Enfermedad , Femenino , Glutatión Peroxidasa/metabolismo , Hígado/irrigación sanguínea , Estrés Oxidativo/efectos de los fármacos , Ratas , Ratas Wistar , Daño por Reperfusión/patología , Daño por Reperfusión/fisiopatología
19.
Ann Gastroenterol ; 25(2): 123-127, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-24714139

RESUMEN

BACKGROUND: Excessive release of gastrin leads to hypertrophy and hyperplasia of enterochromaffin-like cells (ECL) and prolonged stimulation of these cells causes functional impairment. The purpose of this study was to investigate the effect of Helicobacter pylori (H. pylori) infection and long-term proton pump inhibitors (PPI) use on ECL cells. METHODS: Fifteen patients who underwent endoscopy because of dyspeptic symptoms were enrolled in the present study. Biopsies were taken from corpus and antrum and existence of H. pylori was investigated with culture, cytology and CLOtest. The patients were divided into 3 groups. Group-A: H. pylori-negative, never treated previously with PPI; Group-B: H. pylori-positive, never treated previously with PPI; and group-C: H. pylori-negative and continuously treated with PPI for more than 6 months before the subject recruitment period. The features of ECL cell in oxyntic glands were examined with electron microscopy on biopsy specimens. RESULTS: ECL cells were completely normal in Group A. In group B, moderate hyperplasia and vacuolization was seen in ECL cells. In group C, ECL cell hyperplasia was observed and vacuoles with greater amounts of granules in enlarged vesicles were found more intensely in cytoplasm. CONCLUSION: The use of PPI for a long period of time and presence of H. pylori infection are risk factors for ECL hyperplasia.

20.
J Radiat Res ; 52(5): 616-21, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21952316

RESUMEN

Vitamin D has a selective radio and chemosensitizing effect on tumor cells. In vitro and in vivo studies have shown that vitamin D inhibits collagen gel construction, induces type II pneumocyte proliferation and surfactant synthesis in the lungs, and decreases vascular permeability caused by radiation. The aim of this experimental study was to determine if vitamin D has a protective effect against radiation-induced pulmonary damage. Adult Wistar rats were divided into 4 groups. Group 1 was comprised of control animals. Group 2, which was administered 0.25 µg/kg/day of vitamin D3 for 8 weeks, was the vitamin D control group. Rats in groups 3 and 4 were given 20 Gy right hemithorax radiotherapy, and in addition group 4 was given vitamin D3 treatment, which began the day before the radiotherapy and continued for 8 weeks. At the 8(th) and the 12(th) weeks of the study 4 rats from each group were sacrificed. Right lungs were dissected for light and electron microscopic study. The electron microscopy examinations revealed statistically significant differences between group 3 and 4, and in group 4 there was less interstitial inflammation and collagen deposition, and the alveolar structure and the cells lining the alveolar walls were protected. These results confirm that vitamin D has a protective effect against radiation-induced pulmonary toxicity. These findings should be evaluated with further clinical studies.


Asunto(s)
Colecalciferol/farmacología , Neumonitis por Radiación/prevención & control , Animales , Masculino , Microscopía Electrónica de Transmisión , Traumatismos Experimentales por Radiación/patología , Traumatismos Experimentales por Radiación/prevención & control , Neumonitis por Radiación/patología , Protectores contra Radiación/farmacología , Ratas , Ratas Wistar
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