RESUMO
Acquired aplastic anemia (AA) is a life-threatening bone marrow aplasia caused by the autoimmune destruction of hematopoietic stem and progenitor cells. There are no existing diagnostic tests that definitively establish AA, and diagnosis is currently made via systematic exclusion of various alternative etiologies, including inherited bone marrow failure syndromes (IBMFSs). The exclusion of IBMFSs, which requires syndrome-specific functional and genetic testing, can substantially delay treatment. AA and IBMFSs can have mimicking clinical presentations, and their distinction has significant implications for treatment and family planning, making accurate and prompt diagnosis imperative to optimal patient outcomes. We hypothesized that AA could be distinguished from IBMFSs using 3 laboratory findings specific to the autoimmune pathogenesis of AA: paroxysmal nocturnal hemoglobinuria (PNH) clones, copy-number-neutral loss of heterozygosity in chromosome arm 6p (6p CN-LOH), and clonal T-cell receptor (TCR) γ gene (TRG) rearrangement. To test our hypothesis, we determined the prevalence of PNH, acquired 6p CN-LOH, and clonal TRG rearrangement in 454 consecutive pediatric and adult patients diagnosed with AA, IBMFSs, and other hematologic diseases. Our results indicated that PNH and acquired 6p CN-LOH clones encompassing HLA genes have â½100% positive predictive value for AA, and they can facilitate diagnosis in approximately one-half of AA patients. In contrast, clonal TRG rearrangement is not specific for AA. Our analysis demonstrates that PNH and 6p CN-LOH clones effectively distinguish AA from IBMFSs, and both measures should be incorporated early in the diagnostic evaluation of suspected AA using the included Bayesian nomogram to inform clinical application.
Assuntos
Anemia Aplástica , Hemoglobinúria Paroxística , Anemia Aplástica/diagnóstico , Anemia Aplástica/genética , Teorema de Bayes , Criança , Células Clonais , Rearranjo Gênico , Hemoglobinúria Paroxística/diagnóstico , Hemoglobinúria Paroxística/genética , HumanosRESUMO
ABSTRACT: Loturco, I, Suchomel, T, Kobal, R, Arruda, AFS, Guerriero, A, Pereira, LA, and Pai, CN. Force-velocity relationship in three different variations of prone row exercises. J Strength Cond Res 35(2): 300-309, 2021-This study examined the force-velocity relationship and tested the possibility of determining the relative loading intensity percentage of 1 repetition maximum (%1RM) in 3 different variations of prone row exercises. Thirty male top-level athletes from 2 different sports (National Team rugby union players and professional mixed martial arts fighters) were submitted to maximum dynamic strength assessments in the free prone bench pull, bent-over barbell row, and bent-over Smith machine row, after standard procedures encompassing lifts performed from 40 to 100% of 1RM. The mean velocity, mean propulsive velocity, and peak velocity were measured in all attempts. Linear regression analyses were performed to establish the relationships between the different measures of bar velocities and %1RM. The actual (obtained during the assessments) and predicted 1RM values (based on the predictive equations) for each exercise were compared using a paired t-test. In all exercises, the predicted 1RM scores-based on all velocity variables-were not different from their respective actual values. The close linear relationships between bar velocities and distinct %1RM (coefficient of determination ≥80%, in all experimental conditions) allow precise determination of relative load and maximum dynamic strength, and enable coaches and sports scientists to use the different velocity outputs to rapidly and accurately monitor their athletes on a daily basis.
Assuntos
Treinamento Resistido , Levantamento de Peso , Atletas , Exercício Físico , Humanos , Masculino , Força MuscularRESUMO
Prostate cancer cells were transfected with plasmids [empty plasmids, wild-type pcDNA3.1-p53 (V/V), mutant type pcDNA3.1- p53 (G/G)] to analyze the effect of p53 gene polymorphisms on the proliferation, cycle, and apoptosis of prostatic cancer cells. Empty plasmids containing wild-type pcDNA3.1-p53 (V/V) and mutant type pcDNA3.1- p53 (G/G) were used to transfect PC3 and LNCaP cells, respectively. Cell proliferation was detected at 0, 24, 48, and 72 h using the MTT method. Cells were collected at 24 and 72 h. The distribution of cell cycles in various groups was detected using flow cytometry (propidium iodide staining method) and the apoptosis rate was detected using annexin V + propidium iodide double staining. Compared with the control group, wild-type pcDNA3.1-p53 (V/V) and mutant type pcDNA3.1-p53 (G/G) showed a significant inhibitory effect on cell proliferation (P < 0.05); the inhibitory effect of the mutant type was stronger than that of the wild-type. There was no significant difference between PC3 cells and LNCaP cells. After transfection with wild-type pcDNA3.1-p53 (V/V) and mutant type pcDNA3.1-p53 (G/G), PC3 and LNCaP cells were arrested in the G0/G1 stage. Transfection with pcDNA3.1-p53 (G/G) showed a more significant effect than transfection with pcDNA3.1-p53 (V/V). Both the wild-type pcDNA3.1-p53 (V/V) and mutant-type pcDNA3.1-p53 (G/G) led to an increased apoptosis rate of PC3 and LNCaP cells. The p53 gene polymorphism affects the proliferation, apoptosis, and cycle of prostate cancer cells and may serve as a reliable index for the diagnosis and treatment of prostate cancer.
Assuntos
Proliferação de Células/genética , Células Epiteliais/metabolismo , Regulação Neoplásica da Expressão Gênica , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Apoptose , Linhagem Celular Tumoral , Células Epiteliais/patologia , Citometria de Fluxo , Pontos de Checagem da Fase G1 do Ciclo Celular , Humanos , Masculino , Mutação , Plasmídeos/química , Plasmídeos/metabolismo , Próstata/metabolismo , Próstata/patologia , Transfecção , Proteína Supressora de Tumor p53/metabolismoRESUMO
This study examined the mechanism of action of amiloride, a urokinase-type plasminogen activator receptor inhibitor, in lowering proteinuria. Podocytes were resuscitated to allow for their proliferation and were observed for morphological changes. In the in vitro experiment, control, lipopolysaccharide, and lipopolysaccharide + amiloride groups were established. The expression of urokinase-type plasminogen activator receptor (uPAR) in podocytes was detected with a flow cytometer and cell motility was detected with the transwell migration assay. In the in vivo test, the urine protein volume of the model was detected at 24 h using Coomassie brilliant blue staining and the morphological changes of the podocytes were detected with immunofluorescence. The protein expression rate of uPAR in the lipopolysaccharide group was significantly higher than those in the control and lipopolysaccharide + amiloride groups (P < 0.05). The viability of cells in the lipopolysaccharide group was significantly higher than those in the control and lipopolysaccharide + amiloride groups (P < 0.05). Compared with the urine protein level in the control group at 24 h, the level in the lipopolysaccharide group increased significantly (P < 0.05), whereas compared with the urine protein level in the lipopolysaccharide group, the level in the lipopolysaccharide + amiloride group decreased (P < 0.05). uPAR expression was significantly downregulated, and the fusion of the podocyte-specific skelemin synaptopodin on the glomerulus podocytes was significantly decreased in the lipopolysaccharide + amiloride group. These results suggest that amiloride is able to reduce cell motility and thus lower proteinuria by inhibiting the expression of uPAR in podocytes.
Assuntos
Amilorida/farmacologia , Podócitos/efeitos dos fármacos , Podócitos/metabolismo , Proteinúria/metabolismo , Receptores de Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Amilorida/administração & dosagem , Animais , Linhagem Celular Transformada , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , Modelos Animais de Doenças , Expressão Gênica , Camundongos , Podócitos/patologia , Proteinúria/tratamento farmacológico , Proteinúria/urina , Receptores de Ativador de Plasminogênio Tipo Uroquinase/genética , Receptores de Ativador de Plasminogênio Tipo Uroquinase/metabolismoRESUMO
Brain cancer stem cells are a subset of tumor cells present in several types of brain tumor that evade treatment regimens and are responsible for tumor recurrence. Recent reports on several tumors have suggested that Hoechst 33342 dye exclusion is a powerful technique for isolating cancer stem cell-like side population (SP) cells. In the present study, we attempted to isolate the SP cells from medulloblastoma, a malignant brain tumor in children. The tumor samples obtained were subjected to fluorescence-activated cell sorting analysis for SP cell isolation. Further, the SP cells were characterized by a sphere-formation assay and analyzed for expression of stem cell genes by reverse transcription-polymerase chain reaction (RT-PCR). Using flow cytometry, we isolated 2.9% of cancer stem-like SP cells from malignant medulloblastoma, which was reduced to 0.4% in the presence of verapamil, an inhibitor of ABC transporter. These SP cells undergo rapid proliferation and have a high tendency to form tumor spheres when compared with non-SP cells. Further, RT-PCR analysis revealed that the isolated SP cells have increased expression of neural stem cell markers such as nestin, Notch1, and the ABC transporter protein ABCG2. Therefore, our findings suggest that SP cells of medulloblastoma share the characteristics of cancer stem cells. The increased expression of stem cell markers and ABCG2 protein may function collectively and be responsible for drug and apoptosis resistance, as well as tumor recurrence and invasion.
Assuntos
Meduloblastoma/patologia , Células-Tronco Neoplásicas/fisiologia , Membro 2 da Subfamília G de Transportadores de Cassetes de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Pré-Escolar , Expressão Gênica , Humanos , Meduloblastoma/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismo , Células da Side Population/metabolismo , Esferoides Celulares/metabolismoRESUMO
During an epidemic outbreak of neuropathy in Cuba during 1992-1993, blood and urine samples were collected from 107 persons with confirmed neuropathy, from 106 control subjects without clinical abnormality who were broadly matched with the affected persons by age and domicile, and from 537 unmatched subjects, also free from clinical abnormality. The unmatched subjects lived in two locations in Cuba; at each location they were drawn from two age ranges: 11-15-y-old secondary school students and 16-64-y-old adults. Measurements of urinary thiamine and blood transketolase and its activation with thiamine pyrophosphate were made. For the neuropathy subjects, these measurements were repeated after 3 wk of rehabilitation. All groups showed biochemical evidence of thiamine depletion affecting 30-70% of their members, which is a high prevalence. Severity of biochemical depletion was, however, no greater in the neuropathy subjects than in the control subjects (P > 0.05). However, it was greater in Pinar del Rio, where the incidence of disease was higher, than in the city of Havana, where less disease was seen. Although the majority of the affected subjects responded biochemically to a daily oral multivitamin supplement containing thiamine (P < 0.001), in some cases normal biochemical status was not achieved even after 3 wk of intensive treatment. In the affected group, thiamine status was inversely correlated with the amount of alcohol consumed (P = 0.007). Thiamine status at the outset was correlated with clinical outcome after treatment. Although neither thiamine depletion nor alcohol abuse were likely to have been the sole cause of the neuropathy epidemic, they may have been contributory factors. Thiamine supplementation or food fortification may therefore be necessary in Cuba.