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1.
Nanoscale Adv ; 6(15): 3878-3886, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39050953

RESUMO

We employed Density Functional Theory (DFT) to investigate the electronic, magnetic, and optical characteristics of armchair graphene nanoribbons (AGNRs) decorated with neptunium (Np) and plutonium (Pu). Our analysis delves deeply into the intricate orbital hybridizations associated with C-Np, C-Pu, C-C, Np-Np, and Pu-Pu chemical bonds. Through this approach, we explore the electronic band structure, band-decomposed charge densities, spin-charge distributions, and Van Hove singularities in the density of states. Furthermore, our examination successfully correlates optical excitation with electronic band energy. Our results indicated that these rare-earth atoms are strongly bound to the edge structure of AGNRs, significantly altering their electronic, magnetic, and optical properties. Theoretical exploration not only reveals the intriguing physical and chemical properties of rare-earth (Np/Pu) decorated AGNRs but also presents a practical pathway for synthesizing novel materials.

2.
RSC Adv ; 14(23): 16445-16458, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38774611

RESUMO

Using DFT calculations, the structural and electronic properties of the ZZ7 p-PdSe2 nanoribbons (ZZ7) with the four kinds of vacancy defects, including ZZ7-VPd, ZZ7-VSe, ZZ7-VPd+Se, and ZZ7-V2Se are studied, in which their stability, diverse geometries, and altered electronic properties are determined through the formation energies, optimal structural parameters, electronic band structures, and DOSs. Specifically, the formation energies of all studied systems show significant negative values around -3.9 eV, evidencing their good thermal stability. The geometries of four defective structures exhibit different diversification, whereas only the ZZ7-V2Se structure possesses the highly enhanced feature, identified as the most effective substrate for the acetone and acetonitrile adsorption. On the electronic behaviors, the ZZ7 band structure displays the nonmagnetic metallic characteristics that become the ferromagnetic half-metallic band structures for the ZZ7-VPd and ZZ7-VSe and the ferromagnetic semi-metallic band structures for the ZZ7-VPd+Se and ZZ7-V2Se. For adsorption of the acetone and acetonitrile on the ZZ7-V2Se structure, the energetic stability, adsorption sites, adsorption distances, charge transfers, and electronic characteristics of the adsorbed systems are determined by the adsorption energies, optimal adsorption sites, adsorption distances, Mulliken populations, and DOSs. The adsorption energies of the acetone- and acetonitrile-adsorbed ZZ7-V2Se systems display significant values at -1.2 eV and -0.86 eV at the preferable sites of 8 and 11, respectively, indicating their great adsorption ability. The adsorption mechanism of the acetone- and acetonitrile-adsorbed systems belongs to the physisorption owing to absence of chemical bonds, in which the bond lengths of the ZZ7-V2Se substrate show a very small deviation. Under the acetone and acetonitrile adsorptions, the ferromagnetic semi-metallic DOSs of the ZZ7-V2Se become the ferromagnetic half-metallic DOSs for the ZZ7-V2Se-acetone-8 and the ferromagnetic semiconducting DOSs for the ZZ7-V2Se-acetonitrile-11. Our systematic results can provide a complete understanding of the acetone- and acetonitrile adsorptions on the potential ZZ7-V2Se structure, which is very useful for nanosensor application.

3.
AJNR Am J Neuroradiol ; 42(11): 2062-2069, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34556478

RESUMO

BACKGROUND AND PURPOSE: Asymmetries in the circle of Willis have been associated with several conditions, including migraines and stroke, but they may also be age-dependent. This study examined the impact of age and age-dependent changes in cerebral perfusion on circle of Willis anatomy in healthy children and adults. MATERIALS AND METHODS: We performed an observational, cross-sectional study of bright and black-blood imaging of the proximal cerebral vasculature using TOF-MRA and T2 sampling perfection with application-optimized contrasts by using different flip angle evolution (T2-SPACE) imaging at the level of the circle of Willis in 23 healthy children and 43 healthy adults (4-74 years of age). We compared arterial diameters measured manually and cerebral perfusion via pseudocontinuous arterial spin-labeling between children and adults. RESULTS: We found that the summed cross-sectional area of the circle of Willis is larger in children than in adults, though the effect size was smaller with T2-SPACE-based measurements than with TOF-MRA. The circle of Willis is also more symmetric in children, and nonvisualized segments occur more frequently in adults than in children. Moreover, the size and symmetry of the circle of Willis correlate with cerebral perfusion. CONCLUSIONS: Our results demonstrate that the circle of Willis is different in size and symmetry in healthy children compared with adults, likely associated with developmental changes in cerebral perfusion. Further work is needed to understand why asymmetric vasculature develops in some but not all adults.


Assuntos
Círculo Arterial do Cérebro , Angiografia por Ressonância Magnética , Adulto , Criança , Círculo Arterial do Cérebro/diagnóstico por imagem , Estudos Transversais , Humanos , Imageamento por Ressonância Magnética , Marcadores de Spin
4.
Hum Reprod ; 36(10): 2732-2742, 2021 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-34411244

RESUMO

STUDY QUESTION: How is the localisation of ovarian follicles affected by ageing and chronic diseases? SUMMARY ANSWER: Ovarian follicles shift deeper towards the medulla, due to thickening of the tunica albuginea (TA), with ageing and some major common chronic diseases. WHAT IS KNOWN ALREADY: The ovary undergoes morphological and functional changes with ageing. The follicular pool follows these changes with alterations in the amount and distribution of residual follicles. Diseases causing a chronic inflammatory process are associated with morphological changes and impaired ovarian function. STUDY DESIGN, SIZE, DURATION: We conducted a cross-sectional study, examining 90 ovaries from 90 female monkeys. The samples were collected from April 2018 to March 2019 at Tsukuba Primate Research Center in National Institutes of Biomedical Innovation, Health and Nutrition, Japan. PARTICIPANTS/MATERIALS, SETTING, METHODS: Ovarian samples were obtained from cynomolgus monkeys that died from natural causes or were euthanised. Ovarian sections were stained with haematoxylin and eosin (H&E) for histological analyses. In ovarian sections from 64 female macaques aged 0-25 years, a total of 13 743 follicles at different developmental stages (primordial, intermediary, primary, early secondary and late secondary) were assessed to determine the depth of each follicle from the outer surface of the ovarian cortex to the far end of the follicle, by using a digital imaging software. TA thickness was measured as sum of basal membrane and tunica collagen layer for each ovary under H&E staining. To explore the possibility of age-related trends in ovarian morphometric characteristics, samples were divided into four different age groups (0-3 years (pre-menarche), 4-9 years, 10-14 years and 15-20 years). To evaluate the effect of common chronic diseases on ovarian morphometric characteristics, macaques with diabetes mellitus (DM) (n = 10), endometriosis (n = 8) or inflammatory bowel disease (IBD) (n = 8) were compared to age-matched controls without chronic diseases. MAIN RESULTS AND THE ROLE OF CHANCE: Ovarian morphometric analysis revealed that the relative location of follicles became deeper in all age groups according to development of follicles (P < 0.05). Total follicle distance from the ovarian surface was increased with ageing (P < 0.05). In a sub-analysis according to developmental stage, only primordial and intermediary follicles were localised deeper with increasing age (P < 0.05). TA thickness was also increased with ageing (P < 0.05). The localisation of the total number of follicles became deeper in ovaries from monkeys with DM, endometriosis or IBD as compared to the control group (P < 0.05). With DM, analysis of follicles distance at almost each developmental stage was significantly deeper compared to controls (P < 0.05) with the exception of early secondary follicles. With endometriosis, follicles at primary and early and late secondary stages were significantly deeper compared to controls (P < 0.05). Also with IBD, follicles at primary and early and late secondary follicles were significantly deeper compared to controls (P < 0.001). The TA was thicker with DM and endometriosis compared to controls (P < 0.05), but not with IBD (P = 0.16). LARGE SCALE DATA: NA. LIMITATIONS, REASONS FOR CAUTION: Two-dimensional histology was used to assess follicle localisation. The possibility of minimal variations between the measured distance to the actual distance in a spherical structure cannot be excluded. Additionally, the severity of disease was not assessed. WIDER IMPLICATIONS OF THE FINDINGS: This study is the first step towards enhancing our understanding of how ageing and chronic diseases affect the relative localisation of dormant and developing follicles. These observations, combined with possible future human studies, may have managerial implications in the field of fertility preservation and other conditions involving ovarian tissue cryopreservation. STUDY FUNDING/COMPETING INTEREST(S): The present work was supported by the Grant-in-Aid for Scientific Research B (19H03801) (to K.K.), Challenging Exploratory Research (18K19624), Japan Agency for Medical Research and Development, Mochida Memorial Foundation for Medical and Pharmaceutical Research, Takeda Science Foundation and Naito Foundation (to K.K.). All authors have no conflicts of interest directly relevant to the content of this article.


Assuntos
Preservação da Fertilidade , Folículo Ovariano , Animais , Doença Crônica , Estudos Transversais , Feminino , Macaca fascicularis
6.
Clin Transl Sci ; 10(3): 201-207, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28181420

RESUMO

Identifying noninvasive biomarkers of kidney disease is valuable for diagnostic and therapeutic purposes. Hypoxia inducible factor 1 (HIF-1) expression is known to be elevated in the kidneys in several renal disease pathologies. We hypothesized that the urinary HIF-1a mRNA level may be a suitable biomarker for expression of this protein in chronic kidney disease (CKD). We compared HIF-1a mRNA levels from urine pellets of CKD and healthy subjects. To ensure that urinary HIF-1a mRNA is of kidney origin, we examined colocalization of HIF-1a mRNA with two kidney specific markers in urine cells. We found that HIF-1a mRNA is readily quantifiable in urine pellets and its expression was significantly higher in CKD patients compared with healthy adults. We also showed that the urinary HIF-1a mRNA comes primarily from cells of renal origin. Our data suggest that urinary HIF-1a mRNA is a potential biomarker in CKD and can be noninvasively assessed in patients.


Assuntos
Biomarcadores/urina , Fator 1 Induzível por Hipóxia/urina , Insuficiência Renal Crônica/urina , Adulto , Idoso , Caderinas/metabolismo , Creatinina/sangue , Demografia , Feminino , Genes Essenciais , Receptor Celular 1 do Vírus da Hepatite A/genética , Receptor Celular 1 do Vírus da Hepatite A/metabolismo , Humanos , Fator 1 Induzível por Hipóxia/genética , Fator 1 Induzível por Hipóxia/metabolismo , Hibridização in Situ Fluorescente , Rim/metabolismo , Masculino , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Padrões de Referência , Insuficiência Renal Crônica/sangue , Insuficiência Renal Crônica/genética
7.
AJNR Am J Neuroradiol ; 36(12): 2206-13, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26427831

RESUMO

In April 2015, the American Roentgen Ray Society and the American Society of Neuroradiology cosponsored a unique program designed to evaluate the state of the art in the imaging work-up of acute stroke. This topic has grown in importance because of the recent randomized controlled trials demonstrating the clear efficacy of endovascular stroke treatment. The authors, who were participants in that symposium, will highlight the points of emphasis in this article.


Assuntos
Imagem Multimodal/métodos , Acidente Vascular Cerebral/diagnóstico , Embolectomia/métodos , Procedimentos Endovasculares/métodos , Humanos , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/métodos
8.
Cell Tissue Res ; 362(3): 623-32, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26202892

RESUMO

In most pre-clinical animal studies investigating stem cell therapy in acute myocardial infarction (AMI), the administered stem cells are isolated from healthy donors. In clinical practice, however, patients who suffer from AMI will receive autologous cells, for example using adipose-derived stem cells (ASC). During AMI, inflammation is induced and we hypothesized that this might affect characteristics of ASC. To investigate this, ASC were isolated from rat adipose tissue 1 day (1D group, n = 5) or 7 days (7D group, n = 6) post-AMI, and were compared with ASC from healthy control rats (Control group, n = 6) and sham-operated rats (Sham 1D group, n = 5). We found that significantly fewer ASC were present 1 day post-AMI in the stromal vascular fraction (SVF), determined by a colony-forming-unit assay (p < 0.001 vs. Control and 7D). These data were confirmed by flow cytometry, showing fewer CD90-positive cells in SVF of the 1D group. When cultured, no differences were found in proliferation rate and cell size between the groups in the first three passages. Also, no difference in the differentiation capacity of ASC was found. In conclusion, it was shown that significantly fewer stem cells were present in the SVF 1 day post-AMI; however, the stem cells that were present showed no functional differences.


Assuntos
Tecido Adiposo/citologia , Infarto do Miocárdio/patologia , Células-Tronco/citologia , Animais , Contagem de Células , Diferenciação Celular , Linhagem da Célula , Células Cultivadas , Masculino , Ratos Wistar , Células Estromais/citologia
9.
AJNR Am J Neuroradiol ; 35(6): 1045-51, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23598836

RESUMO

Evidence-based medicine has emerged as a valuable tool to guide clinical decision-making, by summarizing the best possible evidence for both diagnostic and treatment strategies. Imaging plays a critical role in the evaluation and treatment of patients with acute ischemic stroke, especially those who are being considered for thrombolytic or endovascular therapy. Time from stroke-symptom onset to treatment is a strong predictor of long-term functional outcome after stroke. Therefore, imaging and treatment decisions must occur rapidly in this setting, while minimizing unnecessary delays in treatment. The aim of this review was to summarize the best available evidence for the diagnostic and therapeutic management of patients with acute ischemic stroke.


Assuntos
Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Terapia Trombolítica/estatística & dados numéricos , Tomografia Computadorizada por Raios X/métodos , Ensaios Clínicos como Assunto , Medicina Baseada em Evidências , Humanos , Prevalência , Prognóstico , Resultado do Tratamento
10.
Haemophilia ; 19(1): 71-5, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23005346

RESUMO

Heavy menstrual bleeding (HMB) is a frequent complaint in adolescence. Although HMB is often caused by immaturity of the hypothalamic-pituitary-ovarian axis, bleeding disorders are another common yet often unidentified cause. The aim of this study was to examine the bleeding patterns and prevalence of inherited bleeding disorders among females referred for HMB to a multidisciplinary adolescent haematology clinic. We retrospectively reviewed the first 105 patients (ages 8-18 years) referred to this specialty clinic from February 2009 to December 2011. Using menstrual bleeding questionnaires and medical records, data were extracted regarding demographics, bleeding patterns, frequency and types of bleeding disorders identified, and prescribed interventions. Sixty-two per cent of patients were diagnosed with a bleeding disorder, including platelet storage pool deficiency (36%), von Willebrand's disease (9%), other platelet function defect (8%), Ehlers-Danlos syndrome (7%) and combined bleeding disorders (2%). Comparison of the bleeding profiles for females with and without a bleeding disorder revealed only three factors that were significantly different, including the reported regularity of patients' periods (P = 0.02), description of period flow (P = 0.04) and number of days of each period that the bleeding was described as 'heavy' (P = 0.007). Bleeding disorders are prevalent in adolescent females presenting to a specialty clinic. Specifically, a relatively high proportion of adolescents were diagnosed with platelet storage pool deficiency. In our small population, menstrual bleeding profiles, as examined by a standardized questionnaire, could not identify females with an underlying bleeding disorder, demonstrating the important role of haemostasis testing in the evaluation of adolescents with HMB.


Assuntos
Transtornos Herdados da Coagulação Sanguínea/epidemiologia , Distúrbios Menstruais/epidemiologia , Menstruação , Adolescente , Criança , Feminino , Humanos , Menstruação/fisiologia , Distúrbios Menstruais/fisiopatologia , Ohio/epidemiologia , Deficiência do Pool Plaquetário/complicações , Prevalência , Estudos Retrospectivos
11.
Stem Cell Res ; 7(3): 219-29, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21907165

RESUMO

Stem cell therapy is a promising tool to improve outcome after acute myocardial infarction (AMI), but needs to be optimized since results from clinical applications remain ambiguous. A potent source of stem cells is the stromal vascular fraction of adipose tissue (SVF), which contains high numbers of adipose derived stem cells (ASC). We hypothesized that: 1) intravenous injection can be used to apply stem cells to the heart. 2) Uncultured SVF cells are easier and safer when cultured ASCs. 3) Transplantation after the acute inflammation period of AMI is favorable over early injection. For this, AMI was induced in rats by 40min of coronary occlusion. One or seven days after AMI, rats were intravenously injected with vehicle, 5×10(6) uncultured rat SVF cells or 1×10(6) rat ASCs. Rats were analyzed 35 days after AMI. Intravenous delivery of both fresh SVF cells and cultured ASCs 7 days after AMI significantly reduced infarct size compared to vehicle. Similar numbers of stem cells were found in the heart, after treatment with fresh SVF cells and cultured ASCs. Importantly, no adverse effects were found after injection of SVF cells. Using cultured ASCs, however, 3 animals had shortness of breath, and one animal died during injection. In contrast to application at 7 days post AMI, injection of SVF cells 1 day post AMI resulted in a small but non-significant infarct reduction (p=0.35). Taken together, intravenous injection of uncultured SVF cells subsequent to the acute inflammation period, is a promising stem cell therapy for AMI.


Assuntos
Tecido Adiposo/citologia , Infarto do Miocárdio/patologia , Infarto do Miocárdio/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Biomarcadores/metabolismo , Vasos Sanguíneos/patologia , Contagem de Células , Diferenciação Celular , Células Cultivadas , Modelos Animais de Doenças , Testes de Função Cardíaca , Injeções Intravenosas , Macrófagos/patologia , Masculino , Infarto do Miocárdio/fisiopatologia , Miócitos Cardíacos/patologia , Ratos , Ratos Wistar , Transplante de Células-Tronco/efeitos adversos , Células Estromais/citologia , Células Estromais/transplante , Tromboembolia/etiologia , Tromboembolia/patologia , Fatores de Tempo
12.
J Neuroimmunol ; 239(1-2): 28-36, 2011 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21890220

RESUMO

IL-6 is an important signaling molecule in the CNS. CNS neurons express IL-6 receptors and their signal transduction molecules, consistent with a role for IL-6 in neuronal physiology. Research indicates that IL-6 levels are low in the normal brain but can be significantly elevated in CNS injury and disease. Relatively little is known about how the elevated levels of IL-6 affect neurons. In the current study we show that under conditions of chronic exposure, IL-6 induces alterations in the level of protein expression in developing CNS cells. Such changes may play a role in the altered CNS function observed in CNS conditions associated with elevated levels of IL-6 in the CNS.


Assuntos
Adaptação Fisiológica/imunologia , Córtex Cerebelar/citologia , Córtex Cerebelar/imunologia , Interleucina-6/farmacologia , Animais , Diferenciação Celular/imunologia , Células Cultivadas , Córtex Cerebelar/metabolismo , Feminino , Interleucina-6/biossíntese , Masculino , Camundongos , Camundongos Transgênicos , Neuroglia/citologia , Neuroglia/imunologia , Neuroglia/metabolismo , Biossíntese de Proteínas/imunologia , Ratos , Ratos Sprague-Dawley , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/farmacologia , Fatores de Tempo
13.
Mol Hum Reprod ; 15(10): 625-31, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19692421

RESUMO

Endometriosis is a common gynecologic disorder characterized by pain and infertility. In addition to estrogen dependence, progesterone resistance is an emerging feature of this disorder. Specifically, a delayed transition from the proliferative to secretory phase as evidenced by dysregulation of progesterone target genes and maintenance of a proliferative molecular fingerprint in the early secretory endometrium (ESE) has been reported. MicroRNAs (miRNAs) are small noncoding RNAs that collectively represent a novel class of regulators of gene expression. In an effort to investigate further the observed progesterone resistance in the ESE of women with endometriosis, we conducted array-based, global miRNA profiling. We report distinct miRNA expression profiles in the ESE of women with versus without endometriosis in a subset of samples previously used in global gene expression analysis. Specifically, the miR-9 and miR-34 miRNA families evidenced dysregulation. Integration of the miRNA and gene expression profiles provides unique insights into the molecular basis of this enigmatic disorder and, possibly, the regulation of the proliferative phenotype during the early secretory phase of the menstrual cycle in affected women.


Assuntos
Endometriose/genética , Endométrio/metabolismo , MicroRNAs/genética , Adulto , Feminino , Humanos , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
14.
Biol Reprod ; 80(1): 105-14, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18815356

RESUMO

Identification of mechanisms underlying endometriosis pathogenesis will facilitate understanding and treatment of infertility and pain associated with this disorder. Herein, we investigated the expression of steroidogenic pathway enzymes and key decidualization biomarkers in endometrial tissue and in eutopic endometrial stromal fibroblasts (hESFs) from women with vs. those without endometriosis, and subsequently treated in vitro with 8-bromo-cAMP (8-Br-cAMP) or progesterone (P4). Real-time quantitative PCR, immunohistochemistry, ELISA, and radiometric aromatase activity assay were used. The results demonstrate significantly increased (14.5-fold; P=0.037) expression of aromatase in eutopic endometrium of women with disease. In 8-Br-cAMP-treated hESF from eutopic endometrium of women with endometriosis, the balance in estradiol (E2) and P4 biosynthetic and metabolizing enzymes is disturbed (decreased HSD3B1 and HSD17B2, and increased HSD17B1 and aromatase), with the equilibrium being shifted towards an E2-enriched milieu. However, hESF from the same group of women treated with P4 did not demonstrate such responsiveness. Lower expression of IGFBP1 and prolactin mRNA and protein was observed in hESF from women with vs. those without endometriosis in response to 8-Br-cAMP, but not P4, suggesting a blunted response of these decidual biomarkers to activation of the PKA pathway in eutopic endometrium in women with disease. The dichotomy of 8-Br-cAMP regulation of select steroidogenic enzymes leading to an enriched E2 milieu within the endometrium and a blunted response of decidual biomarkers to this decidualizing agent of hESF from women with endometriosis suggests resistance to full decidualization of the stromal fibroblasts and mechanisms underlying implantation failure and the pathophysiology of this disorder.


Assuntos
Aromatase/metabolismo , Endometriose/metabolismo , Endométrio/metabolismo , Estradiol Desidrogenases/metabolismo , 8-Bromo Monofosfato de Adenosina Cíclica/farmacologia , Adulto , Aromatase/biossíntese , Aromatase/genética , Decídua/enzimologia , Decídua/metabolismo , Endometriose/enzimologia , Endometriose/patologia , Endométrio/citologia , Endométrio/efeitos dos fármacos , Endométrio/enzimologia , Ensaio de Imunoadsorção Enzimática , Estradiol/biossíntese , Estradiol Desidrogenases/biossíntese , Estradiol Desidrogenases/genética , Feminino , Humanos , Imuno-Histoquímica , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Pessoa de Meia-Idade , Progesterona/biossíntese , Progesterona/farmacologia , Prolactina/metabolismo , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/efeitos dos fármacos , Células Estromais/enzimologia , Células Estromais/metabolismo , Células Estromais/patologia , Adulto Jovem
15.
AJNR Am J Neuroradiol ; 29(1): 18-22, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17925367

RESUMO

Histologically identified intracellular and extracellular inclusions and structures often provide a tissue diagnosis of a specific disease process. Moreover, these deposits may provide clues about the pathogenesis of the disease in which they are found. Two distinctive structures seen within the brains of patients clinically diagnosed with dementia of the Alzheimer type are extracellular plaques and intracellular neurofibrillary tangles. The purpose of this report is to review the significance of plaques and neurofibrillary tangles in the context of Alzheimer disease.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Modelos Neurológicos , Emaranhados Neurofibrilares/metabolismo , Emaranhados Neurofibrilares/patologia , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Doença de Alzheimer/diagnóstico por imagem , Humanos , Modelos Anatômicos , Emaranhados Neurofibrilares/diagnóstico por imagem , Placa Amiloide/diagnóstico por imagem , Radiografia
16.
Endocrinology ; 147(3): 1097-121, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16306079

RESUMO

Histological evaluation of endometrium has been the gold standard for clinical diagnosis and management of women with endometrial disorders. However, several recent studies have questioned the accuracy and utility of such evaluation, mainly because of significant intra- and interobserver variations in histological interpretation. To examine the possibility that biochemical or molecular signatures of endometrium may prove to be more useful, we have investigated whole-genome molecular phenotyping (54,600 genes and expressed sequence tags) of this tissue sampled across the cycle in 28 normo-ovulatory women, using high-density oligonucleotide microarrays. Unsupervised principal component analysis of all samples revealed that samples self-cluster into four groups consistent with histological phenotypes of proliferative (PE), early-secretory (ESE), mid-secretory (MSE), and late-secretory (LSE) endometrium. Independent hierarchical clustering analysis revealed equivalent results, with two major dendrogram branches corresponding to PE/ESE and MSE/LSE and sub-branching into the four respective phases with heterogeneity among samples within each sub-branch. K-means clustering of genes revealed four major patterns of gene expression (high in PE, high in ESE, high in MSE, and high in LSE), and gene ontology analysis of these clusters demonstrated cycle-phase-specific biological processes and molecular functions. Six samples with ambiguous histology were identically assignable to a cycle phase by both principal component analysis and hierarchical clustering. Additionally, pairwise comparisons of relative gene expression across the cycle revealed genes/families that clearly distinguish the transitions of PE-->ESE, ESE-->MSE, and MSE-->LSE, including receptomes and signaling pathways. Select genes were validated by quantitative RT-PCR. Overall, the results demonstrate that endometrial samples obtained by two different sampling techniques (biopsy and curetting hysterectomy specimens) from subjects who are as normal as possible in a human study and including those with unknown histology, can be classified by their molecular signatures and correspond to known phases of the menstrual cycle with identical results using two independent analytical methods. Also, the results enable global identification of biological processes and molecular mechanisms that occur dynamically in the endometrium in the changing steroid hormone milieu across the menstrual cycle in normo-ovulatory women. The results underscore the potential of gene expression profiling for developing molecular diagnostics of endometrial normalcy and abnormalities and identifying molecular targets for therapeutic purposes in endometrial disorders.


Assuntos
Endométrio/metabolismo , Regulação da Expressão Gênica , Ciclo Menstrual/fisiologia , Modelos Biológicos , Ovulação , Doenças Uterinas/genética , Adulto , Algoritmos , Biópsia , Análise por Conglomerados , Regulação para Baixo , Neoplasias do Endométrio/metabolismo , Endométrio/fisiologia , Feminino , Perfilação da Expressão Gênica , Genoma , Humanos , Pessoa de Meia-Idade , Família Multigênica , Análise de Sequência com Séries de Oligonucleotídeos , Fenótipo , Análise de Componente Principal , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Esteroides/metabolismo , Regulação para Cima , Doenças Uterinas/patologia , Útero/metabolismo , Útero/fisiologia
18.
J Comb Chem ; 2(2): 182-5, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10757097

RESUMO

Several substituted 2- and 4-hydroxyacetophenones are linked to Wang resin via a modified Mitsunobu protocol. These resin-bound acetophenones are condensed with aromatic aldehydes, and the resulting chalcones 5 are used for the synthesis of 2-dialkylamino- (9a-d) and 2-alkylamino-4,6-diarylpyridines (11a-f), and 2-alkyl-4,6-diaryl- (14a) and 2,4,6-triarylpyrimidines (14b,c) in a manner suitable for combinatorial applications.


Assuntos
Chalcona/química , Piridinas/síntese química , Pirimidinas/síntese química , Acetofenonas , Aldeídos/síntese química , Indicadores e Reagentes , Resinas Vegetais
19.
Carcinogenesis ; 20(11): 2051-6, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10545405

RESUMO

Scid/scid mice have a mutation in the gene encoding the catalytic subunit of DNA-dependent protein kinase (DNAPK(cs)) and are defective in end joining of DNA double-strand breaks. As a consequence, they are radiosensitive, lack mature T and B lymphocytes and are predisposed to lymphomagenesis. To determine if this DNA repair defect also increased predisposition to skin tumor formation, we treated the dorsal skin of scid/scid mice with the carcinogen 7,12-dimethylbenz[a]anthracene followed by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA). Contrary to expectations, we observed a 5-fold reduction in skin tumor multiplicity in scid/scid mice. We addressed whether this was related to their immunodeficiency by similarly treating Rag1(-/-) and Rag2(-/-) knockout mice which also lack mature T and B lymphocytes. We observed no difference in skin tumor multiplicity for either strain compared with control littermates. This indicates a lack of a significant role for T or B lymphocyte mediated immunity on either papilloma or carcinoma formation. We observed a significant increase in apoptotic and necrotic cell death in follicular and interfollicular epithelial cells of scid/scid mice following TPA treatment. This hypersensitivity of SCID (severe combined immunodeficient) cells to TPA indicates that the resistance to skin tumor formation in scid/scid mice is due to loss of initiated cells through TPA-induced cell killing.


Assuntos
Apoptose/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/genética , Neoplasias Cutâneas/patologia , Acetato de Tetradecanoilforbol/farmacologia , Animais , Proteína Quinase Ativada por DNA , Proteínas de Ligação a DNA/genética , Epiderme/efeitos dos fármacos , Epiderme/patologia , Proteínas de Homeodomínio/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Camundongos SCID , Neoplasias Cutâneas/imunologia
20.
Oncogene ; 18(33): 4689-98, 1999 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-10467416

RESUMO

p27Kip1 and p21Cip1 are cyclin dependent kinase inhibitors which can arrest cell proliferation and p27 is a tumor suppressor gene. To address the mechanism of tumor suppression by p27 and to determine if p21 has a tumor suppressor phenotype, we utilized the two stage skin carcinogenesis model on p27 and p21 knockout mice. In this model, initiation, which involves mutation of H-ras induced by DMBA, can be distinguished from promotion induced by TPA, and progression to carcinoma. The mean number of papillomas did not differ between p27-/- and control littermates, but papilloma growth rate was increased and carcinomas developed earlier. Thus, p27 deficiency did not enhance initiation, but resulted in more rapid clonal expansion of initiated cells during promotion. TPA treatment reduced p27 expression in keratinocytes also supporting a role for p27 during promotion. Tumors from p27-/- mice contained mutant H-ras indicating that p27 deficiency did not substitute for mutant ras and further, that during ras driven tumor growth, p27 is partially antagonistic since its removal led to faster growth. The treated p27-/- mice also developed intestinal adenomas. p21-/- mice did not display a significant increase in tumor numbers, growth rate or progression to carcinomas and these tumors also had mutated H-ras. Carcinomas from p21-/- mice were more poorly differentiated with a high frequency of anaplastic spindle cell carcinomas. Thus p21 deficiency mainly resulted in higher grade undifferentiated tumors.


Assuntos
9,10-Dimetil-1,2-benzantraceno/farmacologia , Proteínas de Ciclo Celular , Transformação Celular Neoplásica , Ciclinas/genética , Proteínas Associadas aos Microtúbulos/genética , Neoplasias Cutâneas/induzido quimicamente , Proteínas Supressoras de Tumor , Adenoma , Animais , Carcinógenos/farmacologia , Carcinoma/induzido quimicamente , Inibidor de Quinase Dependente de Ciclina p21 , Inibidor de Quinase Dependente de Ciclina p27 , Quinases Ciclina-Dependentes/antagonistas & inibidores , Ciclinas/metabolismo , Genes Supressores de Tumor , Genes ras , Neoplasias Intestinais , Queratinócitos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Proteínas Associadas aos Microtúbulos/metabolismo , Mutação , Papiloma/induzido quimicamente , Acetato de Tetradecanoilforbol/farmacologia
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