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1.
BMC Infect Dis ; 23(1): 110, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36823583

RESUMO

BACKGROUND: Rapid determination of an individual's antibody status can be beneficial in understanding an individual's immune response to SARS-CoV-2 and for initiation of therapies that are only deemed effective in sero-negative individuals. Antibody lateral flow tests (LFTs) have potential to address this need as a rapid, point of care test. METHODS: Here we present a proof-of-concept evaluation of eight LFT brands using sera from 95 vaccinated individuals to determine sensitivity for detecting vaccination generated antibodies. Samples were analysed on eight different brands of antibody LFT and an automated chemiluminescent microparticle immunoassay (CMIA) that identifies anti-spike antibodies which was used as our reference standard. RESULTS: All 95 (100%) participants tested positive for anti-spike antibodies by the chemiluminescent microparticle immunoassay (CMIA) reference standard post-dose two of their SARS-CoV-2 vaccine: BNT162b2 (Pfizer/BioNTech, n = 60), AZD1222 (AstraZeneca, n = 31), mRNA-1273 (Moderna, n = 2) and Undeclared Vaccine Brand (n = 2). Sensitivity increased from dose one to dose two in six out of eight LFTs with three tests achieving 100% sensitivity at dose two in detecting anti-spike antibodies. CONCLUSIONS: These tests are demonstrated to be highly sensitive to detect raised antibody levels in vaccinated individuals. RDTs are low cost and rapid alternatives to ELISA based systems.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , Vacina BNT162 , ChAdOx1 nCoV-19 , COVID-19/diagnóstico , COVID-19/prevenção & controle , SARS-CoV-2 , Anticorpos Antivirais , Vacinação
2.
J Endocr Soc ; 6(6): bvac043, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35506145

RESUMO

Context: Meta-analyses report that the low dose short Synacthen test (LDSST) is more sensitive but less specific than the standard dose test for the diagnosis of adrenal insufficiency, and there are concerns regarding the accuracy of dosing in the LDSST. Objective: Perform a retrospective, observational study to review the outcomes of LDSSTs performed in a tertiary endocrine service from 2008 to 2014 (N = 335) and 2016 to 2020 (N = 160), and examine for relationships between cortisol measurements and indication for testing, age and sex. Methods: LDSST were performed by endocrine nurses. Synacthen 500 ng/1.73m2 administered as IV bolus, sampling at 0, 15, 25, and 35 minutes. Results: Mean (± 1SD) baseline cortisol was 221 ± 120 nmol/L, peak 510 ± 166 nmol/L and increment 210 ± 116 nmol/L. 336 (70%) patients had a normal response (baseline cortisol >100 nmol/L, peak >450 nmol/L), 78 (16%) a suboptimal response (peak cortisol 350-450 nmol/L) and were prescribed hydrocortisone to during periods of stress only, 67 (14%) an abnormal response (baseline <100nmol/L or peak <350nmol/L) and were prescribed daily hydrocortisone. Basal, peak, and incremental increases in cortisol were higher in females (P = .03, P < .001, P = .03, respectively). Abnormal results occurred most frequently in patients treated previously with pharmacological doses of glucocorticoids or structural brain abnormalities (P < .001). Conclusion: The low prevalence and strong association of abnormal results with indication for testing, suggests that over diagnosis occurred infrequently in this clinical setting.

3.
Br Dent J ; 231(11): 675-679, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34893725

RESUMO

We are a diverse collective of researchers who are committed to improving the health and wellbeing of marginalised individuals. This article is a response to, and critique of, the DentalSlim Diet Control research. This device revises a controversial 1970s weight-loss technology connected to poor health outcomes, which is indicative of a culture that consistently promotes harm to fat and other marginalised communities.We address the historical context in which unruly bodies, particularly fat, and Indigenous bodies have been the site of unethical investigation conducted under the auspices of medical research. Existence outside the normative white, male, cis physical ideal demands regulation, and disciplinary measures. We demonstrate how Brunton et al.'s research is underpinned by anti-fat attitudes and assumptions which impose this punitive physical intervention onto healthy people in a way that should not be acceptable in medical research.Further, we address a range of harms, giving attention to Maori and to individuals with eating disorders, along with issues of research integrity. We argue that no ethics committee should have approved this research, no academic journal should have published it, and no member of the dental and medical community should promote or prescribe this device.


Assuntos
Formação de Conceito , Mastigação , Humanos , Masculino
4.
Lancet ; 396(10264): 1734-1735, 2020 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-33248491
5.
Movimento (Porto Alegre) ; 25(1): e25065, jan.- dez. 2019.
Artigo em Inglês | LILACS | ID: biblio-1047345

RESUMO

Neste artigo, nós refletimos sobre as possibilidade e responsabilidades da pedagogia crítica em relação ao neoliberalismo e a Educação Física. Ao explorar essas ideias, nós também discutimos os problemas da definição, bem como o colapso e confusão de termos como pedagogia crítica, pesquisa crítica e saúde crítica e Educação Física, bem como a problemática posição do neoliberalismo nos estudos críticos. Embora exista um crescente corpo de pesquisas que iluminam as nuanças e onipresença das políticas e práticas neoliberais em HPE -tanto em contextos globais e em contextos sociais específicos ­ nós argumentamos que ainda existe mais trabalho a ser feito para identificar como o trabalho pedagógico crítico pode dirigir-se (ou ao menos tentar) aos efeitos do neoliberalismo. Ao fim, continua a existir o perigo de que a pedagogia crítica em tempos neoliberais possa transmitir, em vez de contestar, os piores efeitos da escolarização neoliberal e do neoliberalismo em saúde e Educação Física


In this article, we reflect on the possibilities and responsibilities of critical pedagogy in relation to neoliberalism and physical education. In exploring these ideas, we also discuss problems of definition, such as the collapse and confusion of terms like critical pedagogy, critical research, and critical health and PE, as well the problematic positioning of 'neoliberalism' in critical scholarship. Although there is a growing body of research that illuminates the nuances and pervasiveness of neoliberal HPE policies and practices ­ both globally and in specific social contexts ­ we argue that there is still more work to be done to identify how critical pedagogical work may address (or at least attend to) the effects of neoliberalism. After all, there remains a 'danger' that critical pedagogy in neoliberal times may forward, rather than contest, the worst effects of neoliberal schooling and neoliberal HPE


En este artículo, reflexionamos sobre las posibilidades y las responsabilidades de la pedagogía crítica en relación al neoliberalismo y la Educación Física. Además de explorar estas ideas, debatimos los problemas de la definición, así como el colapso y la confusión de los términos como pedagogía crítica, investigación crítica, salud crítica y Educación Física, así como la problemática del neoliberalismo en los estudios críticos. Si bien hay un creciente cuerpo de investigaciones que iluminan los matices y la omnipresencia de las políticas y practicas neoliberales en HPE ­ tanto en los contextos globales como sociales específicos ­ nosotros argumentamos que ha todavia más trabajo por hacer para identificar como el trabajo pedagógico puede dirigirse (o por lo menos intentar) a los efectos del neoliberalismo. Al ultimo, sigue existiendo el peligro de que la pedagogía crítica en tiempos neoliberales pueda transmitir, en lugar de cuestionar, los peores efectos de la escolarización neoliberal y del neoliberalismo en salud y Educación Física


Assuntos
Humanos , Educação Física e Treinamento , Ensino , Educação em Saúde , Economia/tendências
6.
BMJ Case Rep ; 20172017 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-28963385

RESUMO

We report a case of accidental ingestion of model car fuel (Optifuel) resulting in an apparent elevation of serum creatinine of 274 µmol/L (3.1 mg/dL) as measured by the Jaffe (alkaline picrate) reaction, which resulted in an acute kidney injury (AKI) stage 3 alert being reported. Optifuel contains nitromethane, which has been reported to interfere in the Jaffe reaction causing falsely high creatinine measurements. The laboratory staff were vigilant about this potential interfering substance so repeated the analysis of the creatinine using an enzymatic method that showed a markedly lower result of 47 µmol/L (0.5 mg/dL). This report highlights the ability of nitromethane to potentially mimic AKI and the importance of being aware of the limitations of biochemical tests to avoid misinterpretation of results and instigating inappropriate treatment.


Assuntos
Injúria Renal Aguda/diagnóstico , Creatinina/sangue , Óleos Combustíveis/intoxicação , Metano/análogos & derivados , Nitroparafinas/intoxicação , Injúria Renal Aguda/induzido quimicamente , Erros de Diagnóstico , Reações Falso-Positivas , Feminino , Humanos , Indicadores e Reagentes , Metano/intoxicação , Pessoa de Meia-Idade , Picratos
7.
J Exp Clin Cancer Res ; 29: 10, 2010 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-20144232

RESUMO

SIAH proteins are the human members of an highly conserved family of E3 ubiquitin ligases. Several data suggest that SIAH proteins may have a role in tumor suppression and apoptosis. Previously, we reported that SIAH-1 induces the degradation of Kid (KIF22), a chromokinesin protein implicated in the normal progression of mitosis and meiosis, by the ubiquitin proteasome pathway. In human breast cancer cells stably transfected with SIAH-1, Kid/KIF22 protein level was markedly reduced whereas, the Kid/KIF22 mRNA level was increased. This interaction has been further elucidated through analyzing SIAH and Kid/KIF22 expression in both paired normal and tumor tissues and cell lines. It was observed that SIAH-1 protein is widely expressed in different normal tissues, and in cells lines but showing some differences in western blotting profiles. Immunofluorescence microscopy shows that the intracellular distribution of SIAH-1 and Kid/KIF22 appears to be modified in human tumor tissues compared to normal controls. When mRNA expression of SIAH-1 and Kid/KIF22 was analyzed by real-time PCR in normal and cancer breast tissues from the same patient, a large variation in the number of mRNA copies was detected between the different samples. In most cases, SIAH-1 mRNA is decreased in tumor tissues compared to their normal counterparts. Interestingly, in all breast tumor tissues analyzed, variations in the Kid/KIF22 mRNA levels mirrored those seen with SIAH-1 mRNAs. This concerted variation of SIAH-1 and Kid/KIF22 messengers suggests the existence of an additional level of control than the previously described protein-protein interaction and protein stability regulation. Our observations also underline the need to re-evaluate the results of gene expression obtained by qRT-PCR and relate it to the protein expression and cellular localization when matched normal and tumoral tissues are analyzed.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Mama/metabolismo , Proteínas de Ligação a DNA/metabolismo , Cinesinas/metabolismo , Proteínas Nucleares/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Linhagem Celular Tumoral , Feminino , Humanos , Pessoa de Meia-Idade , Proteínas Nucleares/genética , RNA Mensageiro/metabolismo
8.
Anticancer Drugs ; 19(4): 369-79, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18454047

RESUMO

The platinum(II)-based complex cisplatin is one of the most frequently used antitumour agents; however, a high incidence of harmful side effects and the frequent emergence of acquired resistance are the major clinical problems. The novel platinum(IV)-based complex LA-12 exhibits a high efficacy against cancer cell lines, including cisplatin-insensitive cells, but the mechanisms by which LA-12 perturbs cell growth are unclear. We tested the effects of LA-12 on the p53 response and demonstrate that LA-12 induces unique changes in the profile of gene expression compared with cisplatin and doxorubicin. Furthermore, the ability of LA-12 to disrupt cellular proliferation is greatly enhanced by the expression of p53 and p53/47 indicating both p53-dependent and p53-independent effects of LA-12. Exposure of the human cancer cell lines H1299, A2780, BT549 and BT474 to LA-12 alters the expression of p53 and p53/47 in both a time-dependent and dose-dependent manner. Treatment of cells with a low concentration of the drug results in accumulation of p53 and p53/47 concomitant with their posttranslational modification, whereas a high dose results in the disappearance of both the forms of p53. The distinct p53 activation profile of LA-12 compared with cisplatin and doxorubicin provides a molecular explanation for the ability of this drug to treat cisplatin-resistant cells and indicates its potential usefulness as an alternative antitumour agent in first-line therapy or as a second-line therapy in patients with acquired cisplatin resistance.


Assuntos
Amantadina/análogos & derivados , Antineoplásicos/farmacologia , Cisplatino/farmacologia , Compostos Organoplatínicos/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Amantadina/farmacologia , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Doxorrubicina/farmacologia , Resistencia a Medicamentos Antineoplásicos , Citometria de Fluxo , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Processamento de Proteína Pós-Traducional , Transdução de Sinais , Proteína Supressora de Tumor p53/genética
9.
Cell Cycle ; 7(7): 950-9, 2008 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-18414054

RESUMO

P53 plays a key role in the cellular response to damage exposure and in preventing the development of human cancers. Activation of p53 results in changes in the expression of a large number of gene products. However, relatively little is still known how p53 activation differentiates between different types of damages in different types of tissues or how this triggers either an apoptotic response or cell cycle arrest and DNA repair. The p53 message is translated into two products with distinct activities and stabilities through alternative mechanisms of initiation. P53/47 is initiated 40 codons down stream of the full length p53 and does not include the binding site for the E3 ubiquitin ligase Mdm2 or the transactivation domain I but retains the capacity to form p53 hetero- and homo-oligomers. Here we report that p53/47 controls the folding, the oligomerisation and the post-translational modification of p53 complexes and that it diversifies p53 properties in a cell stress-dependent fashion. P21 expression, for example, is under normal conditions not affected by p53/47 but is induced 18-fold after treatment of cells with the DNA damaging drug doxorubicin. This is accompanied by the recruitment of p53/47 to the p21 promoter.


Assuntos
Processamento Alternativo/genética , Dano ao DNA/fisiologia , Regulação Neoplásica da Expressão Gênica/genética , Complexos Multiproteicos/metabolismo , Dobramento de Proteína , Proteína Supressora de Tumor p53/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Dano ao DNA/genética , Primers do DNA/genética , Humanos , Immunoblotting , Análise de Sequência com Séries de Oligonucleotídeos , Isoformas de Proteínas/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína Supressora de Tumor p53/genética
10.
Nat Cell Biol ; 10(9): 1098-105, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19160491

RESUMO

The E3 ubiquitin ligase Mdm2 is a focal regulator of p53 tumour suppressor activity. It binds p53, promoting its polyubiquitination and degradation, and also controls p53 synthesis. However, it is not known how this dual function of Mdm2 on p53 synthesis and degradation is achieved. Here we show that the p53 mRNA region encoding the Mdm2-binding site interacts directly with the RING domain of Mdm2. This impairs the E3 ligase activity of Mdm2 and promotes p53 mRNA translation. We also show that introduction of cancer-derived single silent point-mutations in the p53 mRNA weakens its binding to Mdm2 and results in reduced p53 activity. These data are consistent with a mechanism by which changes in silent nucleotides can affect the function of the encoded protein, and indicate that Mdm2-mediated control of p53 synthesis and degradation has evolved in the p53 mRNA sequence and its encoded amino acids.


Assuntos
Proteínas Proto-Oncogênicas c-mdm2/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Sequência de Bases , Regulação da Expressão Gênica , Humanos , Modelos Biológicos , Ligação Proteica , Biossíntese de Proteínas , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas c-mdm2/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ubiquitina-Proteína Ligases/metabolismo
11.
FASEB J ; 19(3): 461-3, 2005 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15611152

RESUMO

Skeletal muscle is a major insulin target tissue and has a prominent role in the control of body amino acid economy, being the principal store of free and protein-bound amino acids and a dominant locus for amino acid metabolism. Interplay between diverse stimuli (e.g., hormonal/nutritional/mechanical) modulates muscle insulin action to serve physiological need through the action of factors such as intramuscular signaling molecules. Ceramide, a product of sphingolipid metabolism and cytokine signaling, has a potent contra-insulin action with respect to the transport and deposition of glucose in skeletal muscle, although ceramide effects on muscle amino acid turnover have not previously been documented. Here, membrane permeant C2-ceramide is shown to attenuate the basal and insulin-stimulated activity of the Na+-dependent System A amino acid transporter in rat muscle cells (L6 myotubes) by depletion of the plasma membrane abundance of SNAT2 (a System A isoform). Concomitant with transporter down-regulation, ceramide diminished both intramyocellular amino acid abundance and the phosphorylation of translation regulators lying downstream of mTOR. The physiological outcome of ceramide signaling in this instance is a marked reduction in cellular protein synthesis, a result that is likely to represent an important component of the processes leading to muscle wasting in catabolic conditions.


Assuntos
Sistema A de Transporte de Aminoácidos/antagonistas & inibidores , Ceramidas/farmacologia , Células Musculares/metabolismo , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Sistema A de Transporte de Aminoácidos/efeitos dos fármacos , Sistema A de Transporte de Aminoácidos/metabolismo , Sistemas de Transporte de Aminoácidos/análise , Sistemas de Transporte de Aminoácidos/antagonistas & inibidores , Sistemas de Transporte de Aminoácidos/fisiologia , Aminoácidos/análise , Aminoácidos/metabolismo , Animais , Linhagem Celular , Membrana Celular/química , Glucose/metabolismo , Células Musculares/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/química , Músculo Esquelético/efeitos dos fármacos , Proteínas Quinases/metabolismo , Ratos , Transdução de Sinais/efeitos dos fármacos , Serina-Treonina Quinases TOR
12.
Biochem J ; 382(Pt 2): 619-29, 2004 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-15193147

RESUMO

Non-esterified fatty acids (NEFAs) have been implicated in the pathogenesis of skeletal muscle insulin resistance that may develop, in part, as a consequence of a direct inhibitory effect on early insulin signalling events. Here we report work investigating the mechanism by which palmitate (a saturated free fatty acid) inhibits insulin action in rat L6 myotubes. Palmitate suppressed the insulin-induced plasma membrane recruitment and phosphorylation of protein kinase B (PKB) and this was associated with a loss in insulin-stimulated glucose transport. The inhibition in PKB was not due to a loss in insulin receptor substrate (IRS)1 tyrosine phosphorylation, IRS-1/p85 (phosphoinositide 3-kinase) association or suppression in phosphatidyl 3,4,5 triphosphate synthesis, but was attributable to an elevated intracellular synthesis of ceramide (6-fold) from palmitate and a concomitant activation of protein kinase PKCzeta (5-fold). Inhibitors of serine palmitoyl transferase suppressed the intracellular synthesis of ceramide from palmitate, prevented PKCzeta activation, and antagonized the inhibition in PKB recruitment/phosphorylation and the loss in insulin-stimulated glucose transport elicited by the NEFA. Inhibiting the palmitate-induced activation of PKCzeta with Ro 31.8220, also prevented the loss in the insulin-dependent phosphorylation of PKB caused by palmitate. These findings indicate that intracellular ceramide synthesis and PKCzeta activation are important aspects of the mechanism by which palmitate desensitizes L6 muscle cells to insulin.


Assuntos
Ceramidas/biossíntese , Resistência à Insulina/fisiologia , Espaço Intracelular/enzimologia , Espaço Intracelular/metabolismo , Fibras Musculares Esqueléticas/enzimologia , Fibras Musculares Esqueléticas/metabolismo , Palmitatos/metabolismo , Proteína Quinase C/fisiologia , Células 3T3-L1 , Adipócitos , Animais , Linhagem Celular , Ativação Enzimática/fisiologia , Camundongos , Músculo Esquelético/enzimologia , Músculo Esquelético/metabolismo , Ratos
13.
Mol Cell Biol ; 23(21): 7794-808, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14560023

RESUMO

Ceramide is generated in response to numerous stress-inducing stimuli and has been implicated in the regulation of diverse cellular responses, including cell death, differentiation, and insulin sensitivity. Recent evidence indicates that ceramide may regulate these responses by inhibiting the stimulus-mediated activation of protein kinase B (PKB), a key determinant of cell fate and insulin action. Here we show that inhibition of this kinase involves atypical PKCzeta, which physically interacts with PKB in unstimulated cells. Insulin reduces the PKB-PKCzeta interaction and stimulates PKB. However, dissociation of the kinase complex and the attendant hormonal activation of PKB were prevented by ceramide. Under these circumstances, ceramide activated PKCzeta, leading to phosphorylation of the PKB-PH domain on Thr(34). This phosphorylation inhibited phosphatidylinositol 3,4,5-trisphosphate (PIP(3)) binding to PKB, thereby preventing activation of the kinase by insulin. In contrast, a PKB-PH domain with a T34A mutation retained the ability to bind PIP(3) even in the presence of a ceramide-activated PKCzeta and, as such, expression of PKB T34A mutant in L6 cells was resistant to inhibition by ceramide treatment. Inhibitors of PKCzeta and a kinase-dead PKCzeta both antagonized the inhibitory effect of ceramide on PKB. Since PKB confers a prosurvival signal and regulates numerous pathways in response to insulin, suppressing its activation by a PKCzeta-dependent process may be one mechanism by which ceramide promotes cell death and induces insulin resistance.


Assuntos
Ceramidas/metabolismo , Fosfatos de Fosfatidilinositol/metabolismo , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Ativação Enzimática , Inibidores Enzimáticos/metabolismo , Insulina/metabolismo , Substâncias Macromoleculares , Modelos Moleculares , Dados de Sequência Molecular , Peptídeos/genética , Peptídeos/metabolismo , Fosfatos de Fosfatidilinositol/química , Fosforilação , Ligação Proteica , Isoformas de Proteínas/metabolismo , Proteína Quinase C/genética , Estrutura Terciária de Proteína , Proteínas Proto-Oncogênicas/química , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas c-akt , Ratos , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Transdução de Sinais
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