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1.
Intern Med J ; 53(7): 1105-1109, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37032307

RESUMO

Diffuse large B-cell lymphoma (DLBCL) is the most frequent aggressive lymphoma seen in clinical practice. Despite huge strides in understanding its biology, front-line therapy has remained unchanged for decades. Roughly one-third of patients have primary refractory or relapse following the end of conventional first-line therapy. The outcome of patients with primary refractory disease and those with early relapse (defined as relapse less than 1 year from the end of therapy) is markedly inferior to those with later relapse and is exemplified by dismal overall survival. In this article, the authors term patients with features that identify them as being at particularly high-risk for either primary refractory disease or early relapse, as 'ultra-high-risk'. As new treatment options become established (e.g. bispecific T-cell engagers, chimeric antigen receptor 'CAR' T-cells and antibody-drug conjugates), it is likely that there will be a push to incorporate some of these agents into the first-line setting for patients identified as ultra-high-risk. In this review, the authors outline advances in positron emission tomography, widely available laboratory assays and clinical prognosticators, which can detect a high proportion of patients with ultra-high-risk disease. Since these approaches are pragmatic and able to be adopted widely, they could be incorporated into routine clinical practice.


Assuntos
Linfoma Difuso de Grandes Células B , Recidiva Local de Neoplasia , Humanos , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/terapia
2.
Brain Behav ; 12(11): e2801, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36259950

RESUMO

INTRODUCTION: Endothelial nitric oxide synthase (eNOS) produces nitric oxide, which is essential for a variety of physiological functions in the brain. Previous work has demonstrated the detrimental effects of eNOS deficiency on brain function in male eNOS knockout (eNOS KO) mice. However, the effect of eNOS deficiency on brain structure and any association between these effects and sex is unknown. METHODS: This study used three-dimensional high-resolution ex vivo magnetic resonance imaging and behavioral tests of anxiety and cognitive performance to investigate structure-function relationships in the brain of female and male eNOS KO mice in young adulthood. RESULTS: While there were no differences in anxiety-like behavior or locomotion, there was a sex-specific deficit in contextual fear memory retention in male, but not in female, eNOS mice compared to wild-type controls. Moreover, we found that eNOS deficiency induced changes in multiple brain regions that are involved in learning and fear memory including the hippocampus, amygdala, hypothalamus, and areas of the cortex. Several of these MRI-detectable neuroanatomical changes were dependent on sex. CONCLUSION: The observation that eNOS deficiency impacts brain structure at an early age demonstrates the importance of eNOS for healthy brain development.


Assuntos
Encéfalo , Óxido Nítrico Sintase Tipo III , Animais , Feminino , Masculino , Camundongos , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico , Óxido Nítrico Sintase Tipo III/genética
3.
Placenta ; 128: 36-38, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36058049

RESUMO

Placental metabolism determines the amount of nutrients available to the fetus and may be altered in pregnancies complicated by fetal growth restriction (FGR). To study which metabolites are associated with FGR, we performed 1H high-resolution magic angle spinning magnetic resonance spectroscopy of placental tissue from endothelial nitric oxide synthase knockout (eNOS KO) mice, a model of FGR, and C57BL/6J controls at embryonic day 17.5 (n = 24/genotype). The relative concentration of glucose was increased in the placentas of eNOS KO mice compared to controls (p = 0.006). This study highlights the potential for glucose as a biomarker of abnormal placental metabolism that leads to FGR.


Assuntos
Óxido Nítrico Sintase Tipo III , Placenta , Animais , Feminino , Retardo do Crescimento Fetal/patologia , Glucose/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo III/genética , Óxido Nítrico Sintase Tipo III/metabolismo , Placenta/metabolismo , Gravidez
4.
R Soc Open Sci ; 9(3): 211637, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35360348

RESUMO

The design of bioinspired polymers has long been an area of intense study, however, applications to the design of concrete admixtures for improved materials performance have been relatively unexplored. In this work, we functionalized poly(acrylic acid) (PAA), a simple analogue to polycarboxylate ether admixtures in concrete, with dopamine to form a catechol-bearing polymer (PAA-g-DA). Synthetic routes using hydroxybenzotriazole (HOBt) as an activating agent were examined for their ability in grafting dopamine to the PAA backbone. Previous literature using the traditional coupling reagent 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide (EDC) to graft dopamine to PAA were found to be inconsistent and the sensitivity of EDC coupling reactions necessitated a search for an alternative. Additionally, HOBt allowed for greater control over per cent functionalization of the backbone, is a simple, robust reaction, and showed potential for scalability. This finding also represents a novel synthetic pathway for amide bond formation between dopamine and PAA. Finally, we performed preliminary adhesion studies of our polymer on rose granite specimens and demonstrated a 56% improvement in the mean adhesion strength over unfunctionalized PAA. These results demonstrate an early study on the potential of PAA-g-DA to be used for improving the bonds within concrete.

5.
mBio ; 13(2): e0359521, 2022 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-35311534

RESUMO

Due to its high transmissibility, Klebsiella pneumoniae is one of the leading causes of nosocomial infections. Here, we studied the biological cost of colistin resistance, an antibiotic of last resort, in this opportunistic pathogen using a murine model of gut colonization and transmission. Colistin resistance in K. pneumoniae is commonly the result of the inactivation of the small regulatory protein MgrB. Without a functional MgrB, the two-component system PhoPQ is constitutively active, leading to an increase in lipid A modifications and subsequent colistin resistance. Using an isogenic mgrB deletion mutant (MgrB-), we demonstrate that the mutant's colistin resistance is not associated with a fitness defect under in vitro growth conditions. However, in our murine model of K. pneumoniae gastrointestinal (GI) colonization, the MgrB- colonizes the gut poorly, allowing us to identify a fitness cost. Moreover, the MgrB- mutant has higher survival outside the host compared with the parental strain. We attribute this enhanced survivability to dysregulation of the PhoPQ two-component system and accumulation of the master stress regulator RpoS. The enhanced survival of MgrB- may be critical for its rapid host-to-host transmission observed in our model. Together, our data using multiple clinical isolates demonstrate that MgrB-dependent colistin resistance in K. pneumoniae comes with a biological cost in gut colonization. However, this cost is mitigated by enhanced survival outside the host and consequently increases its host-to-host transmission. Additionally, it underscores the importance of considering the entire life cycle of a pathogen to determine the actual biological cost associated with antibiotic resistance. IMPORTANCE The biological cost associated with colistin resistance in Klebsiella pneumoniae was examined using a murine model of K. pneumoniae gut colonization and fecal-oral transmission. A common mutation resulting in colistin resistance in K. pneumoniae is a loss-of-function mutation of the small regulatory protein MgrB that regulates the two-component system PhoPQ. Even though colistin resistance in K. pneumoniae comes with a fitness defect in gut colonization, it increases bacterial survival outside the host enabling it to transmit more effectively to a new host. The enhanced survival is dependent upon the accumulation of RpoS and dysregulation of the PhoPQ. Hence, our study expands our understanding of the underlying molecular mechanism contributing to the transmission of colistin-resistant K. pneumoniae.


Assuntos
Colistina , Infecções por Klebsiella , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Colistina/metabolismo , Colistina/farmacologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/metabolismo , Camundongos
6.
Metabolomics ; 18(1): 10, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34993719

RESUMO

INTRODUCTION: During pregnancy, appropriate placental metabolism is essential for fetuses to reach their growth potential. However, metabolic mechanisms during pregnancy remain poorly understood. Determination of the levels of placental metabolites in healthy pregnancy and how they change throughout gestation is critical for understanding placental function. OBJECTIVE: To determine the effects of gestational age on placental metabolites using healthy pregnant mice. METHODS: In the present study, we collected placental tissue samples from healthy pregnant mice at three timepoints in late gestation (n = 16 placentas per gestational age). Metabolite profiles were determined using 1H high-resolution magic angle spinning magnetic resonance spectroscopy (HRMAS MRS). RESULTS: Using HRMAS MRS, we identified 14 metabolites in murine placental tissue samples. The relative concentration of 12 of the 14 metabolites remains unchanged throughout late gestation. Lysine was found to decrease significantly (p = 0.04) and glucose showed an inverted U-shape relationship (p = 0.03) with gestational age. CONCLUSION: This study demonstrated the feasibility of HRMAS MRS to determine relative metabolite concentrations in murine placental tissue. These findings establish baseline levels of placental tissue metabolite profiles and will serve as reference ranges for future studies using mouse models of fetal distress.


Assuntos
Metabolômica , Placenta , Animais , Feminino , Idade Gestacional , Espectroscopia de Ressonância Magnética/métodos , Camundongos , Placenta/metabolismo , Placenta/patologia , Gravidez
7.
J Autism Dev Disord ; 52(2): 553-568, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33761060

RESUMO

We report a Delphi Consensus modification and first validation study of the Autism Diagnostic Observation Schedule - 2 with deaf children and young people (ADOS-2 Deaf adaptation). Validation included 122 deaf participants (aged 2-18 years), 63 with an Autism Spectrum Disorder (ASD). This was compared to a National Institute for Health and Clinical Excellence (NICE) guideline standard clinical assessment by blinded independent specialist clinicians. Results showed overall sensitivity 73% (95%CI 60%, 83%); specificity 71% (95%CI 58%, 82%), and for the more common modules 1-3 (combined as in previous studies) sensitivity 79% (95% CI 65-89%); specificity 79% (95% CI 66-89%) suggesting this instrument will be a helpful addition for use with deaf children and young people.


Assuntos
Transtorno do Espectro Autista , Transtorno Autístico , Adolescente , Transtorno do Espectro Autista/diagnóstico , Criança , Humanos , Sensibilidade e Especificidade , Especialização
8.
PLoS One ; 16(12): e0260660, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34928958

RESUMO

There has been significant interest in researching the pharmaceutical applications of Industrial hemp since its legalization three years ago. The crop is mostly dioecious and known for its production of phytocannabinoids, flavonoids, and terpenes. Although many scientific reports have showed gene expression analysis of hemp through OMICs approaches, unreliable reference genes for normalization of qRT-PCR data make it difficult to validate the OMICs data. Four software packages: geNorm, NormFinder, BestKeeper, and RefFinder were used to evaluate the differential gene expression patterns of 13 candidate reference genes under osmotic, heavy metal, hormonal, and UV stresses. EF-1α ranked as the most stable reference gene across all stresses, TUB was the most stable under osmotic stress, and TATA was the most stable under both heavy metal stress and hormonal stimuli. The expression patterns of two cannabinoid pathway genes, AAE1 and CBDAS, were used to validate the reliability of the selected reference genes. This work provides useful information for gene expression characterization in hemp and future research in the synthesis, transport, and accumulation of secondary metabolites.


Assuntos
Cannabis/genética , Genes de Plantas , Proteínas de Plantas/normas , Reação em Cadeia da Polimerase em Tempo Real/normas , Canabinoides/química , Canabinoides/metabolismo , Regulação da Expressão Gênica de Plantas , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/normas , Proteínas de Plantas/genética , RNA de Plantas/metabolismo , Estresse Fisiológico/genética , Tubulina (Proteína)/genética , Tubulina (Proteína)/normas
9.
Muscle Nerve ; 64(4): 428-434, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34076273

RESUMO

INTRODUCTION/AIMS: Since 2016, six states have legalized physician-hastened death (PHD). Neuromuscular disorders, including amyotrophic lateral sclerosis (ALS), are common diagnoses for patients who use PHD, but how patients with ALS view PHD in California has not been systematically studied. We aimed to quantify how many patients with ALS and their caregivers have considered PHD and to assess reasons to consider using or not using it. METHODS: This is a cross-sectional study at one ALS center surveying patients with ALS and their caregivers. Data on disease characteristics, demographics, quality of life, and depression were also collected. Descriptive statistics were used to analyze the data. Qualitative data were also collected and analyzed. Patients were followed up longitudinally to assess if they died or if they used PHD. RESULTS: A small majority of ALS patients surveyed had considered or would consider using PHD (16/30). Patients most commonly described having intolerable symptoms, being a burden on their loved ones, and losing independence as reasons to consider using PHD. Many patients shared that "their life has purpose" and "they are making the most of their lives" as to why they are not considering PHD. Considering PHD was not related to disease severity or depression. On longitudinal follow-up, 10 of the 30 patients have died, and none have used PHD. DISCUSSION: Pursuing PHD is a personal decision for each individual patient. This study shows that considering PHD is relatively common in ALS patients, independent of disease severity or presence of depression.


Assuntos
Esclerose Lateral Amiotrófica/psicologia , Cuidadores/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Participação do Paciente/psicologia , Papel do Médico/psicologia , Suicídio Assistido/psicologia , Adaptação Psicológica/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Esclerose Lateral Amiotrófica/epidemiologia , Esclerose Lateral Amiotrófica/terapia , California/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Participação do Paciente/métodos
10.
J Mol Biol ; 433(10): 166953, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33771571

RESUMO

Aberrant aggregation and amyloid formation of tar DNA binding protein (TDP-43) and α-synuclein (αS) underlie frontotemporal dementia (FTD) and Parkinson's disease (PD), respectively. Amyloid inclusions of TDP-43 and αS are also commonly co-observed in amyotrophic lateral sclerosis (ALS), dementia with Lewy bodies (DLB) and Alzheimer disease (AD). Emerging evidence from cellular and animal models show colocalization of the TDP-43 and αS aggregates, raising the possibility of direct interactions and co-aggregation between the two proteins. In this report, we set out to answer this question by investigating the interactions between αS and prion-like pathogenic C-terminal domain of TDP-43 (TDP-43 PrLD). PrLD is an aggregation-prone fragment generated both by alternative splicing as well as aberrant proteolytic cleavage of full length TDP-43. Our results indicate that two proteins interact in a synergistic manner to augment each other's aggregation towards hybrid fibrils. While monomers, oligomers and sonicated fibrils of αS seed TDP-43 PrLD monomers, TDP-43 PrLD fibrils failed to seed αS monomers indicating selectivity in interactions. Furthermore, αS modulates liquid droplets formed by TDP-43 PrLD and RNA to promote insoluble amyloid aggregates. Importantly, the cross-seeded hybrid aggregates show greater cytotoxicity as compared to the individual homotypic aggregates suggesting that the interactions between the two proteins have a discernable impact on cellular functions. Together, these results bring forth insights into TDP-43 PrLD - αS interactions that could help explain clinical and pathological presentations in patients with co-morbidities involving the two proteins.


Assuntos
Amiloide/química , Proteínas de Ligação a DNA/química , Neurônios/efeitos dos fármacos , RNA/química , alfa-Sinucleína/química , Processamento Alternativo , Amiloide/genética , Amiloide/metabolismo , Amiloide/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Proteínas de Ligação a DNA/toxicidade , Humanos , Gotículas Lipídicas/química , Gotículas Lipídicas/metabolismo , Neurônios/citologia , Neurônios/metabolismo , Príons/química , Príons/genética , Príons/metabolismo , Príons/toxicidade , Agregados Proteicos/genética , Ligação Proteica , Domínios Proteicos , Proteólise , RNA/genética , RNA/metabolismo , Sonicação , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo , alfa-Sinucleína/toxicidade
11.
Biol Sex Differ ; 12(1): 26, 2021 03 10.
Artigo em Inglês | MEDLINE | ID: mdl-33691774

RESUMO

BACKGROUND: Fetal sex is known to affect pregnancy outcomes. In current clinical practice, monitoring of fetal well-being is based on Doppler ultrasound measurements of major placental and fetal vessels. The objective of this study was to investigate the effect of fetal sex on Doppler parameters throughout gestation in healthy pregnancy. METHODS: A prospective study was conducted in 240 pregnant women with ultrasound examinations at a 4-weekly interval between 12 and 38 weeks of gestation. Pulsed Doppler spectra were collected for the umbilical arteries (UAs), middle cerebral artery (MCA), descending abdominal aorta (DAo), and ductus venosus (DV). Linear mixed effects models were used to determine if the pulsatility indices (PIs) of these vessels depended on gestational age and fetal sex. RESULTS: While there were no differences in the MCA PI and DV PIV over gestation between female and male fetuses, the trajectory of the UA and DAo PIs differed by fetal sex (p = 0.02 and p = 0.01, respectively). CONCLUSIONS: Doppler ultrasound parameters were found to be dependent on fetal sex for some vessels and not for others in healthy pregnancies. Further investigations are needed to understand the physiological mechanisms for these sex differences and the relevance for disease processes in pregnancy.


Assuntos
Caracteres Sexuais , Ultrassonografia Pré-Natal , Feminino , Humanos , Masculino , Placenta/diagnóstico por imagem , Gravidez , Estudos Prospectivos , Ultrassonografia Doppler
12.
Front Plant Sci ; 11: 580621, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33363552

RESUMO

Industrial hemp (Cannabis sativa L.) is a diploid (2n = 20), dioecious plant that is grown for fiber, seed, and oil. Recently, there has been a renewed interest in this crop because of its panoply of cannabinoids, terpenes, and other phenolic compounds. Specifically, hemp contains terpenophenolic compounds such as cannabidiol (CBD) and cannabigerol (CBG), which act on cannabinoid receptors and positively regulate various human metabolic, immunological, and physiological functions. CBD and CBG have an effect on the cytokine metabolism, which has led to the examination of cannabinoids on the treatment of viral diseases, including COVID-19. Based on genomic, transcriptomic, and metabolomic studies, several synthetic pathways of hemp secondary metabolite production have been elucidated. Nevertheless, there are few reports on hemp metabolic engineering despite obvious impact on scientific and industrial sectors. In this article, recent status and current perspectives on hemp metabolic engineering are reviewed. Three distinct approaches to expedite phytochemical yield are discussed. Special emphasis has been placed on transgenic and transient gene delivery systems, which are critical for successful metabolic engineering of hemp. The advent of new tools in synthetic biology, particularly the CRISPR/Cas systems, enables environment-friendly metabolic engineering to increase the production of desirable hemp phytochemicals while eliminating the psychoactive compounds, such as tetrahydrocannabinol (THC).

13.
Biomacromolecules ; 21(10): 4280-4293, 2020 10 12.
Artigo em Inglês | MEDLINE | ID: mdl-32786526

RESUMO

Saccharide stereochemistry plays an important role in carbohydrate functions such as biological recognition processes and protein binding. Synthetic glycopolymers with pendant saccharides of controlled stereochemistry provide an attractive approach for the design of polysaccharide-inspired biomaterials. Acrylamide-based polymers containing either ß,d-glucose or ß,d-galactose pendant groups, designed to mimic GM1 ganglioside saccharides, and their small-molecule analogues were used to evaluate the effect of stereochemistry on glycopolymer solution aggregation processes alone and in the presence of Aß42 peptide using dynamic light scattering, gel permeation chromatography-multiangle laser light scattering, and fluorescence assays. Fourier transform infrared and nuclear magnetic resonance (NMR) were employed to determine hydrogen bonding patterns of the systems. The galactose-containing polymer displayed significant intramolecular hydrogen bonding and self-aggregation and minimal association with Aß42, while the glucose-containing glycopolymers showed intermolecular interactions with the surrounding environment and association with Aß42. Saturation transfer difference NMR spectroscopy demonstrated different binding affinities for the two glycopolymers to Aß42 peptide.


Assuntos
Peptídeos beta-Amiloides , Polímeros , Gangliosídeo G(M1) , Galactose , Ligação de Hidrogênio
14.
Elife ; 92020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32720894

RESUMO

Precise control and maintenance of population size is fundamental for organismal development and homeostasis. The three cell types of the mammalian blastocyst are generated in precise proportions over a short time, suggesting a mechanism to ensure a reproducible outcome. We developed a minimal mathematical model demonstrating growth factor signaling is sufficient to guarantee this robustness and which anticipates an embryo's response to perturbations in lineage composition. Addition of lineage-restricted cells both in vivo and in silico, causes a shift of the fate of progenitors away from the supernumerary cell type, while eliminating cells using laser ablation biases the specification of progenitors toward the targeted cell type. Finally, FGF4 couples fate decisions to lineage composition through changes in local growth factor concentration, providing a basis for the regulative abilities of the early mammalian embryo whereby fate decisions are coordinated at the population level to robustly generate tissues in the right proportions.


Assuntos
Blastocisto/metabolismo , Diferenciação Celular/genética , Linhagem da Célula/genética , Embrião de Mamíferos/embriologia , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Animais , Camundongos , Modelos Biológicos , Transdução de Sinais
15.
Reprod Toxicol ; 93: 137-145, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32084500

RESUMO

Chronic kidney disease (CKD) affects over 15 % of the adults in the United States. Pregnant women with CKD present an additional challenge in that they are at increased risk for adverse events such as preterm birth. Exposure to environmental toxicants, such as methylmercury, may exacerbate maternal disease and increase the risk of adverse fetal outcomes. We hypothesized that fetuses of mothers with CKD are more susceptible to accumulation of methylmercury than fetuses of healthy mothers. The current data show that when mothers are in a state of renal insufficiency, uptake of mercury in fetal kidneys is enhanced significantly. Accumulation of Hg in fetal kidneys may be related to the flow of amniotic fluid, maternal handling of Hg, and/or underdeveloped mechanisms for cellular export and urinary excretion. The results of this study indicate that renal insufficiency in mothers leads to significant alterations in the way toxicants such as mercury are handled by maternal and fetal organs.


Assuntos
Poluentes Ambientais/farmacocinética , Feto/metabolismo , Troca Materno-Fetal , Mercúrio/metabolismo , Compostos de Metilmercúrio/farmacocinética , Insuficiência Renal Crônica/metabolismo , Líquido Amniótico/química , Animais , Encéfalo/metabolismo , Poluentes Ambientais/toxicidade , Fezes/química , Feminino , Humanos , Recém-Nascido , Rim/efeitos dos fármacos , Rim/metabolismo , Rim/patologia , Masculino , Mercúrio/sangue , Mercúrio/urina , Compostos de Metilmercúrio/toxicidade , Placenta/química , Gravidez , Ratos Wistar , Distribuição Tecidual , Útero/metabolismo
16.
Biol Trace Elem Res ; 195(1): 187-195, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31332705

RESUMO

Mercury (Hg) is a common environmental toxicant to which humans are exposed regularly through occupational and dietary means. Although selenium supplementation has been reported to prevent the toxic effects of Hg in animals, the mechanisms for this prevention are not well understood. The purpose of the current study was to determine the effects of selenium on the disposition and toxicity of Hg. Wistar rats were injected intravenously with a non-nephrotoxic dose (0.5 µmol kg-1) or a nephrotoxic dose (2.5 µmol kg-1) of HgCl2 (containing radioactive Hg) with or without co-administration of sodium selenite (Na2SeO3). Twenty-four hours after exposure, rats were euthanized, and organs were harvested. Co-administration of SeO32- with HgCl2 reduced the renal burden of Hg and the urinary excretion of Hg while increasing the amount of Hg in blood and spleen. We propose that Hg reacts with reduced selenite in the blood to form large Hg-Se complexes that are unable to be filtered at the glomerulus. Consequently, these complexes remain in the blood and are able to accumulate in blood-rich organs. These complexes, which may have fewer toxic effects than other species of Hg, may be eliminated slowly over the course of weeks to months.


Assuntos
Cloreto de Mercúrio/toxicidade , Mercúrio/metabolismo , Selenito de Sódio/farmacologia , Animais , Feminino , Injeções Intravenosas , Íons/metabolismo , Rim/efeitos dos fármacos , Rim/metabolismo , Masculino , Cloreto de Mercúrio/administração & dosagem , Cloreto de Mercúrio/sangue , Ratos , Ratos Wistar , Selenito de Sódio/administração & dosagem , Selenito de Sódio/sangue , Baço/efeitos dos fármacos , Baço/metabolismo , Distribuição Tecidual
17.
Front Psychol ; 10: 997, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143143

RESUMO

Disturbance in how one's body shape and size is experienced, usually including over-estimation of one's own body size, is a core feature of the diagnostic criteria of anorexia nervosa (AN). Is this over-estimation specific to women with AN's judgments of their own body? Or is it just a general feature of their judgments about all bodies? If the latter, it would be consistent with a general error in the perception of body size potentially linked to the use of a different set of visual cues for judging body size. If the former, then this suggests that the over-estimation of own body size has a strong attitudinal component and may be part of the psycho-pathology of their condition. To test this hypothesis, 20 women with AN and 80 control observers estimated the body size of 46 women. The results show a strong effect of perceptual factors in estimating body size for both controls and women with AN. This result is consistent with size over-estimation of own body in AN having a strong attitudinal basis and being a core feature of the psycho-pathology of the condition.

18.
J Hand Ther ; 32(1): 103-109, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29102478

RESUMO

STUDY DESIGN: Clinical measurement study. INTRODUCTION: The push-off test (POT) was recently conceived and found to be reliable and valid for assessing weight bearing through injured wrist or elbow. However, further research with larger sample can lend credence to the preliminary findings supporting the use of the POT. PURPOSE OF THE STUDY: This study examined the interrater reliability, construct validity, and measurement error for the POT in patients with wrist conditions. METHODS: Participants with musculoskeletal (MSK) wrist conditions were recruited. The performance on the POT, grip isometric strength of wrist extensors was assessed. The shortened version of the Disabilities of the Arm, Shoulder and Hand and numeric pain rating scale were completed. The intraclass correlation coefficient assessed interrater reliability of the POT. Pearson correlation coefficients (r) examined the concurrent relationships between the POT and other measures. The standard error of measurement and the minimal detectable change at 90% confidence interval were assessed as measurement error and index of true change for the POT. RESULTS: A total of 50 participants with different elbow or wrist conditions (age: 48.1 ± 16.6 years) were included in this study. The results of this study strongly supported the interrater reliability (intraclass correlation coefficient: 0.96 and 0.93 for the affected and unaffected sides, respectively) of the POT in patients with wrist MSK conditions. The POT showed convergent relationships with the grip strength on the injured side (r = 0.89) and the wrist extensor strength (r = 0.7). The POT showed smaller standard error of measurement (1.9 kg). The minimal detectable change at 90% confidence interval for the POT was 4.4 kg for the sample. CONCLUSIONS: This study provides additional evidence to support the reliability and validity of the POT. This is the first study that provides the values for the measurement error and true change on the POT scores in patients with wrist MSK conditions. Further research should examine the responsiveness and discriminant validity of the POT in patients with wrist conditions.


Assuntos
Teste de Esforço , Extremidade Superior/fisiologia , Suporte de Carga/fisiologia , Articulação do Cotovelo/fisiopatologia , Feminino , Força da Mão/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Dinamômetro de Força Muscular , Reprodutibilidade dos Testes , Articulação do Punho/fisiopatologia
19.
J Toxicol Environ Health A ; 81(24): 1246-1256, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30507365

RESUMO

Humans throughout the world are exposed regularly to mixtures of environmental toxicants. Four of the most common heavy metal toxicants in the environment are mercury (Hg), cadmium (Cd), lead (Pb), and arsenic (As). Numerous studies have assessed the effects and disposition of individual metals in organ systems; however, humans are usually exposed to mixtures of toxicants or metals rather than to a single toxicant. Therefore, the purpose of the current study was to test the hypothesis that exposure to a mixture of toxic heavy metals alters the disposition of single metals in target organs. Wistar rats (Rattus norvegicus) were exposed to Hg, Cd, Pb, or As as a single metal or as a mixture of metals. Rats were injected intravenously for three days, following which kidneys, liver, brain, and blood were harvested. Samples were analyzed for content of Hg, Cd, Pb, and As via inductively coupled plasma mass spectrometry. In general, exposure to a mixture of metals reduced accumulation of single metals in target organs. Interestingly, exposure to mixtures of metals with Pb and/or As increased the concentration of these metals specifically in the liver. The findings from this study indicate that exposure to mixtures of toxic heavy metals may alter significantly the distribution and accumulation of these metals in target organs and tissues.

20.
Biol Trace Elem Res ; 186(1): 9-11, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29478229

RESUMO

Methylmercury (CH3Hg+), a common environmental toxicant, has serious detrimental effects in numerous organ systems. We hypothesize that a significant physiological change, like pregnancy, can alter the disposition and accumulation of mercury. To test this hypothesis, pregnant and non-pregnant female Wistar rats were exposed orally to CH3Hg+. The amount of mercury in blood and total renal mass was significantly lower in pregnant rats than in non-pregnant rats. This finding may be due to expansion of plasma volume in pregnant rats and dilution of mercury, leading to lower levels of mercury in maternal blood and kidneys.


Assuntos
Rim/metabolismo , Compostos de Metilmercúrio/sangue , Compostos de Metilmercúrio/metabolismo , Administração Oral , Animais , Feminino , Compostos de Metilmercúrio/administração & dosagem , Gravidez , Ratos , Ratos Wistar
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