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1.
Clin Radiol ; 78(8): 576-583, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37308350

RESUMO

AIM: To generate standardised coronal minimum intensity projection (MinIP) computed tomography (CT) reconstructions, and compare these with flexible bronchoscopy in children with lymphobronchial tuberculosis (LBTB). MATERIALS AND METHODS: Standardised coronal MinIP reconstructions were performed from CT images in children with LBTB and the findings of three readers were compared with the reference standard, flexible bronchoscopy (FB), regarding airway narrowing. Intraluminal lesions, the site of the stenosis, and the degree of stenosis were also evaluated. The length of stenosis was evaluated by CT MinIP only. RESULTS: Sixty-five children (38 males; 58.5% and 27 females; 41.5%), with ages ranging from 2.5 to 144 months were evaluated. Coronal CT MinIP demonstrated a sensitivity of 96% and specificity of 89% against FB. The most common site of stenosis was the bronchus intermedius (91%), followed by the left main bronchus (85%), the right upper lobe bronchus RUL (66%), and the trachea (60%). CONCLUSION: Coronal CT MinIP reconstruction is useful in demonstrating airway stenosis in children with lymphobronchial TB, with high sensitivity and specificity. CT MinIP had additional advantages over FB in that it allowed objective measurement of the diameter of stenosis, measurement of the length of stenosis, and evaluation of post-stenotic segments of the airways and lung parenchymal abnormalities.


Assuntos
Broncoscopia , Tuberculose , Masculino , Feminino , Humanos , Criança , Broncoscopia/métodos , Constrição Patológica/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Brônquios/diagnóstico por imagem
2.
Nanotechnology ; 32(6): 065704, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33108770

RESUMO

Exchange bias (EB) effects linked to surface spin freezing (SSF) are commonly found in iron oxide nanoparticles, while signatures of SSF in low-field temperature-dependent magnetization curves have been much less frequently reported. Here, we present magnetic properties of dense assemblies of similar-sized (∼8 nm diameter) particles synthesized by a magnetite (sample S1) and a maghemite (sample S2) method, and the influence of long-term (4 year) sample aging under ambient conditions on these properties. The size of the EB field of the different sample (fresh or aged) states is found to correlate with (a) whether a low-temperature hump feature signaling the SSF transition is detected in out-of-phase ac susceptibility or zero-field-cooled (ZFC) dc magnetization recorded at low field and with (b) the prominence of irreversibility between FC and ZFC curves recorded at high field. Sample S1 displays a lower magnetization than S2, and it is in S1 where the largest SSF effects are found. These effects are significantly weakened by aging but remain larger than the SSF effects in S2, where the influence of aging is considerably smaller. A non-saturating component due to spin disorder in S1 also weakens with aging, accompanied by, we infer, an increase in the superspin and the radius of the ordered nanoparticle cores. X-ray diffraction and Mössbauer spectroscopy provide indication of maghemite-like stoichiometry in both aged samples as well as thicker disordered particle shells in aged-S1 relative to aged-S2 (crystallographically-disordered and spin-disordered according to diffraction and Mössbauer, respectively). The pronounced diminution in SSF effects with aging in S1 is attributed to a (long-term) transition, caused by ambient oxidation, from magnetite-like to maghemite-like stoichiometry, and a concomitant softening of the spin-disordered shell anisotropy. We assess the impact of this anisotropy on the nature of the blocking of the nanoparticle superspins.

3.
Clin Radiol ; 76(4): 315.e1-315.e7, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33558027

RESUMO

AIM: To determine the normal range of head and neck lymph nodes in a paediatric population. MATERIALS AND METHODS: A retrospective review was undertaken of 200 brain magnetic resonance imaging (MRI) examinations in patients aged between 5 months to 16 years. Exclusion criteria included possible causes for lymphadenopathy. Studies were reported previously as normal. Eight regions were assessed for the presence of nodes, short and long axis of the largest node measured, and the ratio was calculated. RESULTS: Most commonly identifiable nodes were the deep cervical, submandibular, and posterior cervical in 100%, 99.5%, and 92.5% of studies. In the long axis, the three largest were the submandibular, deep, and posterior cervical with mean values of 19.7, 18.1, and 15.4 mm, respectively. For the S/L ratio, the three with the most oval shape were the pre-auricular, occipital, and submental with ratios of 0.64, 0.63, and 0.6, respectively. A positive correlation between the occipital and deep cervical lymph node groups with age was found to be stronger than the rest of localisations. CONCLUSION: This study characterises the normal distribution, size, and shape of head and neck lymph nodes in a healthy paediatric population, demonstrating that rounder and larger lymph nodes may be a normal finding, depending on their location and patient age.


Assuntos
Cabeça/diagnóstico por imagem , Linfonodos/anatomia & histologia , Linfonodos/diagnóstico por imagem , Pescoço/diagnóstico por imagem , Adolescente , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Valores de Referência , Estudos Retrospectivos
4.
Clin Radiol ; 76(3): 163-171, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33097229

RESUMO

Term neonatal bowel obstruction is common, and absence of treatment is potentially catastrophic. There is a relatively narrow differential diagnosis, with causes categorised as either low or high bowel obstruction. The commonest causes of low bowel obstruction include anorectal malformations (ARM), Hirschsprung's disease, ileal atresia, meconium ileus, meconium plug, and colonic atresia. The commonest causes of high bowel obstruction include duodenal atresia, duodenal stenosis/web, jejunal atresia, and malrotation with volvulus (and hypertrophic pyloric stenosis usually presenting in slightly older infants). Diagnosis can be decided using a step-wise binary decision tool that includes the appropriate imaging steps and evaluation of bowel calibre. This paper presents the decision-making tool from the presenting features, through plain radiographic findings and, where necessary, the additional radiological investigations to assist the general radiologist, novice paediatric radiologist and paediatric surgeon. The tool is pictorial, with the radiological findings accompanied by eight schematics, serving as a simplified visual aid for memorizing the imaging patterns of the differential diagnosis. The imaging and decision-making steps allow for a rapid, simplified diagnosis that can benefit patients by recommending when to perform surgery, when to perform further imaging, and when imaging can act in a therapeutic manner.


Assuntos
Tomada de Decisão Clínica/métodos , Diagnóstico por Imagem/métodos , Obstrução Intestinal/diagnóstico por imagem , Humanos , Recém-Nascido , Intestinos/diagnóstico por imagem
5.
Int J Mol Sci ; 22(14)2021 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-34298909

RESUMO

To ascertain the role of Zn(II) as an allosteric modulator on P2X4R, QM/MM molecular dynamic simulations were performed on the WT and two P2X4R mutants suggested by previous electrophysiological data to affect Zn(II) binding. The Gibbs free energy for the reduction of the putative P2X4R Zn(II) binding site by glutathione was estimated at -22 kcal/mol. Simulations of the WT P2X4R head domain revealed a flexible coordination sphere dominated by an octahedral geometry encompassing C126, N127, C132, C149, C159 and a water molecule. The C132A mutation disrupted the metal binding site, leading to a coordination sphere with a majority of water ligands, and a displacement of the metal ion towards the solvent. The C132A/C159A mutant exhibited a tendency towards WT-like stability by incorporating the R148 backbone to the coordination sphere. Thus, the computational findings agree with previous experimental data showing Zn(II) modulation for the WT and C132A/C159A variants, but not for the C132A mutant. The results provide molecular insights into the nature of the Zn(II) modulation in P2X4R, and the effect of the C132A and C132A/C159A mutations, accounting for an elusive modulation mechanism possibly occurring in other extracellular or membrane protein.


Assuntos
Cisteína/metabolismo , Domínios Proteicos/fisiologia , Proteína Ribossômica L10/metabolismo , Zinco/metabolismo , Ligantes , Proteínas de Membrana/metabolismo , Metais/metabolismo , Simulação de Dinâmica Molecular , Ligação Proteica/fisiologia , Receptores Purinérgicos P2X4 , Água/metabolismo
6.
Int J Mol Sci ; 21(18)2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32971737

RESUMO

P2 × 4R is allosterically modulated by Zn(II), and despite the efforts to understand the mechanism, there is not a consensus proposal; C132 is a critical amino acid for the Zn(II) modulation, and this residue is located in the receptor head domain, forming disulfide SS3. To ascertain the role of the SS2/SS3 microenvironment on the rP2 × 4R Zn(II)-induced allosteric modulation, we investigated the contribution of each individual SS2/SS3 cysteine plus carboxylic acid residues E118, E160, and D170, located in the immediate vicinity of the SS2/SS3 disulfide bonds. To this aim, we combined electrophysiological recordings with protein chemical alkylation using thiol reagents such as N-ethylmaleimide or iodoacetamide, and a mutation of key amino acid residues together with P2 × 4 receptor bioinformatics. P2 × 4R alkylation in the presence of the metal obliterated the allosteric modulation, a finding supported by the site-directed mutagenesis of C132 and C149 by a corresponding alanine. In addition, while E118Q was sensitive to Zn(II) modulation, the wild type receptor, mutants E160Q and D170N, were not, suggesting that these acid residues participate in the modulatory mechanism. Poisson-Boltzmann analysis indicated that the E160Q and D170N mutants showed a shift towards more positive electrostatic potential in the SS2/SS3 microenvironment. Present results highlight the role of C132 and C149 as putative Zn(II) ligands; in addition, we infer that acid residues E160 and D170 play a role attracting Zn(II) to the head receptor domain.


Assuntos
Receptores Purinérgicos P2X4/metabolismo , Zinco/metabolismo , Regulação Alostérica/fisiologia , Substituição de Aminoácidos , Animais , Humanos , Mutação de Sentido Incorreto , Domínios Proteicos , Receptores Purinérgicos P2X4/genética , Xenopus laevis
7.
BMC Urol ; 19(1): 92, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31619215

RESUMO

BACKGROUND: Fatigue is one of the most prevalent symptoms among cancer patients. Specifically, in metastatic castration-resistant prostate cancer (mCRPC) patients, fatigue is the most common adverse event associated with current treatments. The purpose of this study is to describe the prevalence of fatigue and its impact on quality of life (QoL) in patients with CRPC in routine clinical practice. METHODS: This was a cross-sectional, multicentre study. Male chemo-naïve adults with high-risk non-metastatic (M0) CRPC and metastatic (M1) CRPC (mCRPC) were eligible. Fatigue was measured using the Brief Fatigue Inventory (BFI) and QoL was assessed using the Functional Assessment of Cancer Therapy questionnaire for patients with prostate cancer (FACT-P) and the FACT-General (FACT-G) questionnaire. Data were analysed using Mann-Whitney or Kruskal-Wallis tests (non-parametric distribution), a T-test or an ANOVA (parametric distribution) and the Fisher or chi-squared tests (categorical variables). RESULTS: A total of 235 eligible patients were included in the study (74 [31.5%] with M0; and 161 [68.5%] with M1). Fatigue was present in 74%, with 38.5% of patients reporting moderate-to-severe fatigue. Mean FACT-G and FACT-P overall scores were 77.6 ± 16.3 and 108.7 ± 21.4, respectively, with no differences between the CRPC M0 and CRPC M1 subgroups. Fatigue intensity was associated with decreased FACT-G/P scores, with no differences between groups. Among 151 mCRPC patients with available treatment data, those treated with abiraterone-prednisone ≥3 months showed a significant reduction in fatigue intensity (p = 0.043) and interference (p = 0.04) compared to those on traditional hormone therapy (HT). Patients on abiraterone-prednisone ≥3 months showed significantly better FACT-G/P scores than patients on HT (p = 0.046 and 0.018, respectively). CONCLUSION: Our data show a high prevalence and intensity of fatigue and its impact on QoL in chemo-naïve CRPC patients. There is an association between greater fatigue and less QoL, irrespective of the presence or absence of metastasis. Chemo-naïve mCRPC patients receiving more than 3 months of abiraterone acetate plus prednisone showed an improvement of fatigue and QoL when compared to those on traditional HT. TRIAL REGISTRATION: Not applicable since it is not an interventional study.


Assuntos
Fadiga/epidemiologia , Fadiga/etiologia , Neoplasias de Próstata Resistentes à Castração/complicações , Qualidade de Vida , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência
8.
Purinergic Signal ; 14(2): 121-139, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29349673

RESUMO

Endothelial cells participate in extracellular ATP release elicited by mechanosensors. To characterize the dynamic interactions between mechanical and chemical factors that modulate ATP secretion by the endothelium, we assessed and compared the mechanisms participating in the spontaneous (basal) and mechanically stimulated secretion using primary cultures of rat mesentery endothelial cells. ATP/metabolites were determined in the cell media prior to (basal) and after cell media displacement or a picospritzer buffer puff used as mechanical stimuli. Mechanical stimulation increased extracellular ATP that peaked within 1 min, and decayed to basal values in 10 min. Interruption of the vesicular transport route consistently blocked the spontaneous ATP secretion. Cells maintained in media lacking external Ca2+ elicited a spontaneous rise of extracellular ATP and adenosine, but failed to elicit a further extracellular ATP secretion following mechanical stimulation. 2-APB, a TRPV agonist, increased the spontaneous ATP secretion, but reduced the mechanical stimulation-induced nucleotide release. Pannexin1 or connexin blockers and gadolinium, a Piezo1 blocker, reduced the mechanically induced ATP release without altering spontaneous nucleotide levels. Moreover, thrombin or related agonists increased extracellular ATP secretion elicited by mechanical stimulation, without modifying spontaneous release. In sum, present results allow inferring that the spontaneous, extracellular nucleotide secretion is essentially mediated by ATP containing vesicles, while the mechanically induced secretion occurs essentially by connexin or pannexin1 hemichannel ATP transport, a finding fully supported by results from Panx1-/- rodents. Only the latter component is modulated by thrombin and related receptor agonists, highlighting a novel endothelium-smooth muscle signaling role of this anticoagulant.


Assuntos
Trifosfato de Adenosina/metabolismo , Células Endoteliais/metabolismo , Mecanotransdução Celular/fisiologia , Canais de Cátion TRPV/metabolismo , Trombina/metabolismo , Animais , Células Cultivadas , Masculino , Mesentério/citologia , Mesentério/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Ratos , Ratos Sprague-Dawley
9.
Phys Chem Chem Phys ; 20(45): 28634-28643, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30406239

RESUMO

This paper aims to analyze the competition of single particle anisotropy and interparticle interactions in nanoparticle ensembles using a random anisotropy model. The model is first applied to ideal systems of non-interacting and strongly dipolar interacting ensembles of maghemite nanoparticles. The investigation is then extended to more complex systems of pure cobalt ferrite CoFe2O4 (CFO) and mixed cobalt-nickel ferrite (Co,Ni)Fe2O4 (CNFO) nanoparticles. Both samples were synthetized by the polyol process and exhibit the same particle size (DTEM ≈ 5 nm), but with different interparticle interaction strengths and single particle anisotropy. The implementation of the random anisotropy model allows investigation of the influence of single particle anisotropy and interparticle interactions, and sheds light on their complex interplay as well as on their individual contribution. This analysis is of fundamental importance in order to understand the physics of these systems and to develop technological applications based on concentrated magnetic nanoparticles, where single and collective behaviors coexist.

10.
Clin Exp Dermatol ; 42(4): 403-405, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28247460

RESUMO

Urticarial vasculitis (UV) is a mainly leucocytoclastic vasculitis with urticarial plaques. Treating these patients is challenging as the available treatments have poor efficacy. Oral corticosteroids are considered the first-line treatment, but H1 antihistamines, dapsone, colchicine, antimalarials, ciclosporin and antileucotrienes have all been tried also. However, because of their adverse effects and/or lack of efficacy, new agents are still needed. Omalizumab, an anti-IgE antibody, shows efficacy in chronic spontaneous urticaria, and might also be a good treatment for angio-oedema and urticarial vasculitis. To our knowledge, there have been only seven relevant case reports published in the English literature. We add a new case of severe chronic recurrent urticarial vasculitis refractory to all of the drugs mentioned above. We started the patient on subcutaneous omalizumab 300 mg every 4 weeks, which produced clinical improvement within the first month and total remission in the fifth month. The patient has remained stable for 23 months, and follow-up is ongoing.

11.
Nanotechnology ; 25(10): 105702, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24532090

RESUMO

Porous films of Co/CoO magnetic nanoparticles have been obtained by inert gas condensation and partially oxidized in situ in the deposition chamber. These nanoparticle films were subjected to thermal treatments in high vacuum and the chemical and structural changes monitored by x-ray diffraction, transmission electron microscopy, transport and magnetic measurements (with a focus on the exchange-bias phenomenon), which evidence that for vacuum annealing temperatures above 360 °C, most of the CoO phase is reduced to metallic Co without requiring the presence of an external reducing agent (e.g., H2) or a plasma. Additionally, there is a certain degree of particle coalescence resulting in the formation of greater nanoparticles as the annealing temperature increases. This yields a smaller proportion of CoO compared to metallic Co and a reduction of the Co/CoO interface density, pinpointed by a drastic decrease of the exchange-bias field. The crucial roles of the vacuum level and the surface-to-volume ratio are evidenced by magnetic measurements, highlighting the potential of magnetometry as a probe for the reduction/oxidation of composite nanostructures.

12.
Pharmacol Rev ; 63(3): 641-83, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21737531

RESUMO

Mammalian ATP-gated nonselective cation channels (P2XRs) can be composed of seven possible subunits, denoted P2X1 to P2X7. Each subunit contains a large ectodomain, two transmembrane domains, and intracellular N and C termini. Functional P2XRs are organized as homomeric and heteromeric trimers. This review focuses on the binding sites involved in the activation (orthosteric) and regulation (allosteric) of P2XRs. The ectodomains contain three ATP binding sites, presumably located between neighboring subunits and formed by highly conserved residues. The detection and coordination of three ATP phosphate residues by positively charged amino acids are likely to play a dominant role in determining agonist potency, whereas an AsnPheArg motif may contribute to binding by coordinating the adenine ring. Nonconserved ectodomain histidines provide the binding sites for trace metals, divalent cations, and protons. The transmembrane domains account not only for the formation of the channel pore but also for the binding of ivermectin (a specific P2X4R allosteric regulator) and alcohols. The N- and C- domains provide the structures that determine the kinetics of receptor desensitization and/or pore dilation and are critical for the regulation of receptor functions by intracellular messengers, kinases, reactive oxygen species and mercury. The recent publication of the crystal structure of the zebrafish P2X4.1R in a closed state provides a major advance in the understanding of this family of receptor channels. We will discuss data obtained from numerous site-directed mutagenesis experiments accumulated during the last 15 years with reference to the crystal structure, allowing a structural interpretation of the molecular basis of orthosteric and allosteric ligand actions.


Assuntos
Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/metabolismo , Agonistas do Receptor Purinérgico P2X/farmacologia , Antagonistas do Receptor Purinérgico P2X/farmacologia , Receptores Purinérgicos P2X/química , Receptores Purinérgicos P2X/metabolismo , Animais , Sítios de Ligação , Humanos , Metais/farmacologia , Metais/toxicidade , Proteínas do Tecido Nervoso/genética , Conformação Proteica , Isoformas de Proteínas/agonistas , Isoformas de Proteínas/antagonistas & inibidores , Isoformas de Proteínas/química , Isoformas de Proteínas/metabolismo , Receptores Purinérgicos P2X/genética
13.
Actas Urol Esp (Engl Ed) ; 48(3): 218-227, 2024 Apr.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-37574011

RESUMO

INTRODUCTION: The management of patients with prostate cancer (PCa) is established in clinical practice guidelines, which are based on randomized studies according to the level of evidence. In Spain, the degree of compliance with these guidelines in clinical practice is unknown. OBJECTIVES: To describe the profiles of PCa patients at the time of diagnosis and the management of patients with localized PCa and those with BCR in Spain. MATERIALS & METHODS: A medical survey was conducted in specialized care (85 urologists [UROs], 64 radiation oncologists [ROs], and 21 medical oncologists [MOs]). Three questionnaires were developed for this study with 22 (UROs and ROs) or 21 questions (MOs). RESULTS: The annual incidence of PCa was 24,057 in participating hospitals (N = 131). The extrapolated annual incidence in Spain is 40,531 cases. The estimated prevalence of PCa in Spain is 221,689. Of note, 79% and 80% of patients seen by UROs and ROs, respectively had localized PCa at diagnosis. Biopsy was the most used diagnostic test among the three specialties, followed by abdominopelvic computer tomography. More than 90% of patients with BCR underwent standard tests. Next generation imaging tests and PET-choline/PSMA are still used residually. Most patients with localized PCa are currently treated with either surgery or radiotherapy, while for BCR patients, UROs and ROs prefer radiotherapy and MOs androgen deprivation therapy alone or in combination. CONCLUSION: This study describes patient profiles at the time of diagnosis and provides an overview of the current therapeutic management of localized PCa and BCR in clinical practice in Spain.


Assuntos
Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/epidemiologia , Neoplasias da Próstata/terapia , Espanha/epidemiologia , Antagonistas de Androgênios , Espécies Reativas de Oxigênio , Inquéritos e Questionários
14.
Eur J Pharmacol ; 975: 176636, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38729417

RESUMO

Endothelial cells express multiple receptors mediating estrogen responses; including the G protein-coupled estrogen receptor (GPER). Past studies on nitric oxide (NO) production elicited by estrogens raised the question whether 17-ß-estradiol (E2) and natural phytoestrogens activate equivalent mechanisms. We hypothesized that E2 and phytoestrogens elicit NO production via coupling to distinct intracellular pathways signalling. To this aim, perfusion of E2 and phytoestrogens to the precontracted rat mesentery bed examined vasorelaxation, while fluorescence microscopy on primary endothelial cells cultures quantified single cell NO production determined following 4-amino-5-methylamino-2',7'-difluoroescein diacetate (DAF) incubation. Daidzein (DAI) and genistein (GEN) induced rapid vasodilatation associated to NO production. Multiple estrogen receptor activity was inferred based on the reduction of DAF-NO signals; G-36 (GPER antagonist) reduced 75 % of all estrogen responses, while fulvestrant (selective nuclear receptor antagonist) reduced significantly more the phytoestrogens responses than E2. The joint application of both antagonists abolished the E2 response but not the phytoestrogen-induced DAF-NO signals. Wortmannin or LY-294002 (PI3K inhibitors), reduced by 90% the E2-evoked signal while altering significantly less the DAI-induced response. In contrast, H-89 (PKA inhibitor), elicited a 23% reduction of the E2-induced signal while blocking 80% of the DAI-induced response. Desmethylxestospongin-B (IP3 receptor antagonist), decreased to equal extent the E2 or the DAI-induced signal. Epidermal growth factor (EGF) induced NO production, cell treatment with AG-1478, an EGF receptor kinase inhibitor reduced 90% DAI-induced response while only 53% the E2-induced signals; highlighting GPER induced EGF receptor trans-modulation. Receptor functional selectivity may explain distinct signalling pathways mediated by E2 and phytoestrogens.


Assuntos
Proteínas Quinases Dependentes de AMP Cíclico , Receptores ErbB , Estradiol , Óxido Nítrico , Fosfatidilinositol 3-Quinases , Fitoestrógenos , Transdução de Sinais , Vasodilatação , Animais , Fitoestrógenos/farmacologia , Estradiol/farmacologia , Óxido Nítrico/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Vasodilatação/efeitos dos fármacos , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Receptores ErbB/metabolismo , Masculino , Isoflavonas/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Genisteína/farmacologia , Receptores de Estrogênio/metabolismo , Ratos Wistar
15.
Br J Cancer ; 108(6): 1378-86, 2013 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-23361049

RESUMO

BACKGROUND: The chromosome 9p21.3 region has been implicated in the pathogenesis of multiple cancers. METHODS: We systematically examined up to 203 tagging SNPs of 22 genes on 9p21.3 (19.9-32.8 Mb) in eight case-control studies: thyroid cancer, endometrial cancer (EC), renal cell carcinoma, colorectal cancer (CRC), colorectal adenoma (CA), oesophageal squamous cell carcinoma (ESCC), gastric cardia adenocarcinoma and osteosarcoma (OS). We used logistic regression to perform single SNP analyses for each study separately, adjusting for study-specific covariates. We combined SNP results across studies by fixed-effect meta-analyses and a newly developed subset-based statistical approach (ASSET). Gene-based P-values were obtained by the minP method using the Adaptive Rank Truncated Product program. We adjusted for multiple comparisons by Bonferroni correction. RESULTS: Rs3731239 in cyclin-dependent kinase inhibitors 2A (CDKN2A) was significantly associated with ESCC (P=7 × 10(-6)). The CDKN2A-ESCC association was further supported by gene-based analyses (Pgene=0.0001). In the meta-analyses by ASSET, four SNPs (rs3731239 in CDKN2A, rs615552 and rs573687 in CDKN2B and rs564398 in CDKN2BAS) showed significant associations with ESCC and EC (P<2.46 × 10(-4)). One SNP in MTAP (methylthioadenosine phosphorylase) (rs7023329) that was previously associated with melanoma and nevi in multiple genome-wide association studies was associated with CRC, CA and OS by ASSET (P=0.007). CONCLUSION: Our data indicate that genetic variants in CDKN2A, and possibly nearby genes, may be associated with ESCC and several other tumours, further highlighting the importance of 9p21.3 genetic variants in carcinogenesis.


Assuntos
Biomarcadores Tumorais/genética , Cromossomos Humanos Par 9/genética , Inibidor de Quinase Dependente de Ciclina p15/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Humanos , Metanálise como Assunto , Prognóstico
16.
Nat Genet ; 28(4): 376-80, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11455388

RESUMO

Hermansky-Pudlak syndrome (HPS) is a rare autosomal recessive disorder characterized by oculocutaneous albinism and a storage pool deficiency due to an absence of platelet dense bodies. Lysosomal ceroid lipofuscinosis, pulmonary fibrosis and granulomatous colitis are occasional manifestations of the disease. HPS occurs with a frequency of one in 1800 in north-west Puerto Rico due to a founder effect. Several non-Puerto Rican patients also have mutations in HPS1, which produces a protein of unknown function. Another gene, ADTB3A, causes HPS in the pearl mouse and in two brothers with HPS-2 (refs. 11,12). ADTB3A encodes a coat protein involved in vesicle formation, implicating HPS as a disorder of membrane trafficking. We sought to identify other HPS-causing genes. Using homozygosity mapping on pooled DNA of 6 families from central Puerto Rico, we localized a new HPS susceptibility gene to a 1.6-cM interval on chromosome 3q24. The gene, HPS3, has 17 exons, and a putative 113.7-kD product expected to reveal how new vesicles form in specialized cells. The homozygous, disease-causing mutation is a large deletion and represents the second example of a founder mutation causing HPS on the small island of Puerto Rico. We also present an allele-specific assay for diagnosing individuals heterozygous or homozygous for this mutation.


Assuntos
Proteínas de Transporte/genética , Cromossomos Humanos Par 3/genética , Síndrome de Hermanski-Pudlak/genética , Alelos , Sequência de Aminoácidos , Northern Blotting , Análise Mutacional de DNA , Feminino , Efeito Fundador , Triagem de Portadores Genéticos , Predisposição Genética para Doença , Genótipo , Síndrome de Hermanski-Pudlak/epidemiologia , Homozigoto , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Dados de Sequência Molecular , Mutação , Especificidade de Órgãos , Linhagem , Fenótipo , Mapeamento Físico do Cromossomo , Porto Rico/epidemiologia , Deleção de Sequência
17.
Nucleic Acids Res ; 38(2): 618-32, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19889724

RESUMO

In this study, we demonstrate the identification of an internal ribosome entry site (IRES) within the 5'-untranslated region (5'-UTR) of the mouse mammary tumor virus (MMTV). The 5'-UTR of the full-length mRNA derived from the infectious, complete MMTV genome was cloned into a dual luciferase reporter construct containing an upstream Renilla luciferase gene (RLuc) and a downstream firefly luciferase gene (FLuc). In rabbit reticulocyte lysate, the MMTV 5'-UTR was capable of driving translation of the second cistron. In vitro translational activity from the MMTV 5'-UTR was resistant to the addition of m(7)GpppG cap-analog and cleavage of eIF4G by foot-and-mouth disease virus (FMDV) L-protease. IRES activity was also demonstrated in the Xenopus laevis oocyte by micro-injection of capped and polyadenylated bicistronic RNAs harboring the MMTV-5'-UTR. Finally, transfection assays showed that the MMTV-IRES exhibits cell type-dependent translational activity, suggesting a requirement for as yet unidentified cellular factors for its optimal function.


Assuntos
Regiões 5' não Traduzidas , Vírus do Tumor Mamário do Camundongo/genética , Iniciação Traducional da Cadeia Peptídica , RNA Viral/química , Animais , Linhagem Celular , Humanos , Luciferases de Vaga-Lume/análise , Luciferases de Vaga-Lume/genética , Proteínas de Transporte Nucleocitoplasmático/metabolismo , Oócitos/metabolismo , Plasmídeos/genética , Regiões Promotoras Genéticas , Capuzes de RNA/antagonistas & inibidores , RNA Mensageiro/química , Coelhos , Xenopus laevis , Produtos do Gene rev do Vírus da Imunodeficiência Humana/metabolismo
19.
Front Pharmacol ; 13: 1031223, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36744214

RESUMO

The vesicular nucleotide transporter (VNUT) is critical for sympathetic co-transmission and purinergic transmission maintenance. To examine this proposal, we assessed whether the bisphosphonate clodronate, claimed as a potent in vitro VNUT blocker, modified spontaneous and/or the electrically evoked overflow of ATP/metabolites and NA from mesentery sympathetic perivascular nerve terminals. Additionally, in primary endothelial cell cultures derived from this tissue, we also evaluated whether clodronate interfered with ATP/metabolite cell outflow and metabolism of N6-etheno adenosine 5'-triphosphate (eATP), N6-etheno adenosine (eADO), and adenosine deaminase enzyme activity. Rat mesenteries were perfused in the absence or presence of .01-1,000 nM clodronate, 1-1,000 nM Evans blue (EB), and 1-10 µM DIDS; tissue perfusates were collected to determine ATP/metabolites and NA before, during, and after perivascular electrical nerve terminal depolarization. An amount of 1-1,000 nM clodronate did not modify the time course of ATP or NA overflow elicited by nerve terminal depolarization, and only 10 nM clodronate significantly augmented perfusate adenosine. Electrical nerve terminal stimulation increased tissue perfusion pressure that was significantly reduced only by 10 nM clodronate [90.0 ± 18.6 (n = 8) to 35.0 ± 10.4 (n = 7), p = .0277]. As controls, EB, DIDS, or reserpine treatment reduced the overflow of ATP/metabolites and NA in a concentration-dependent manner elicited by nerve terminal depolarization. Moreover, mechanical stimulation of primary endothelial cell cultures from the rat mesentery added with 10 or 100 nM clodronate increased adenosine in the cell media. eATP was metabolized by endothelial cells to the same extent with and without 1-1,000 nM clodronate, suggesting the bisphosphonate did not interfere with nucleotide ectoenzyme metabolism. In contrast, extracellular eADO remained intact, indicating that this nucleoside is neither metabolized nor transported intracellularly. Furthermore, only 10 nM clodronate inhibited (15.5%) adenosine metabolism to inosine in endothelial cells as well as in a commercial crude adenosine deaminase enzyme preparation (12.7%), and both effects proved the significance (p < .05). Altogether, present data allow inferring that clodronate inhibits adenosine deaminase activity in isolated endothelial cells as in a crude extract preparation, a finding that may account for adenosine accumulation following clodronate mesentery perfusion.

20.
Med Intensiva (Engl Ed) ; 46(4): 179-191, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35461665

RESUMO

OBJECTIVE: The objective of the study is to identify the risk factors associated with mortality at six weeks, especially by analyzing the role of antivirals and munomodulators. DESIGN: Prospective descriptive multicenter cohort study. SETTING: 26 Intensive care units (ICU) from Andalusian region in Spain. PATIENTS OR PARTICIPANTS: Consecutive critically ill patients with confirmed SARS-CoV-2 infection were included from March 8 to May 30. INTERVENTIONS: None. VARIABLES: Variables analyzed were demographic, severity scores and clinical condition. Support therapy, drug and mortality were analyzed. An univariate followed by multivariate Cox regression with propensity score analysis was applied. RESULTS: 495 patients were enrolled, but 73 of them were excluded for incomplete data. Thus, 422 patients were included in the final analysis. Median age was 63 years and 305 (72.3%) were men. ICU mortality: 144/422 34%; 14 days mortality: 81/422 (19.2%); 28 days mortality: 121/422 (28.7%); 6-week mortality 152/422 36.5%. By multivariable Cox proportional analysis, factors independently associated with 42-day mortality were age, APACHE II score, SOFA score at ICU admission >6, Lactate dehydrogenase at ICU admission >470U/L, Use of vasopressors, extrarenal depuration, %lymphocytes 72h post-ICU admission <6.5%, and thrombocytopenia whereas the use of lopinavir/ritonavir was a protective factor. CONCLUSION: Age, APACHE II, SOFA>value of 6 points, along with vasopressor requirements or renal replacement therapy have been identified as predictor factors of mortality at six weeks. Administration of corticosteroids showed no benefits in mortality, as did treatment with tocilizumab. Lopinavir/ritonavir administration is identified as a protective factor.


Assuntos
COVID-19 , SARS-CoV-2 , Estudos de Coortes , Estado Terminal , Feminino , Mortalidade Hospitalar , Humanos , Lactente , Lopinavir/uso terapêutico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Ritonavir/uso terapêutico
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