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1.
bioRxiv ; 2023 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-37577570

RESUMO

Western blot is a popular biomolecular analysis method for measuring the relative quantities of independent proteins in complex biological samples. However, variability in quantitative western blot data analysis poses a challenge in designing reproducible experiments. The lack of rigorous quantitative approaches in current western blot statistical methodology may result in irreproducible inferences. Here we describe best practices for the design and analysis of western blot experiments, with examples and demonstrations of how different analytical approaches can lead to widely varying outcomes. To facilitate best practices, we have developed the blotRig tool for designing and analyzing western blot experiments to improve their rigor and reproducibility. The blotRig application includes functions for counterbalancing experimental design by lane position, batch management across gels, and analytics with covariates and random effects.

2.
J Spinal Cord Med ; 46(6): 910-916, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-35604340

RESUMO

Activity-based recovery training (ABRT) reverses spinal cord injury (SCI) induced polyuria and alterations of biomarkers involved with fluid balance, including expression levels of kidney vasopressin 2 receptors. However, void volumes do not return to pre-injury baseline levels, indicating a combinatorial approach may be necessary.In the current study, acute effects of a pharmacological intervention versus placebo were examined in male rats that had received 70 daily ABRT sessions. The treatment, desmopressin (DDAVP - synthetic analogue of arginine vasopressin), an antidiuretic therapy used for the management of bedwetting in children and central diabetes insipidus, has previously shown some promise in a few limited cohorts of SCI individuals having nocturnal polyuria.A total of 70 sessions of ABRT over a 10-week timeframe again reduced the overproduction of urine, but not completely to pre-SCI baseline levels. DDAVP treatment maintained but did not further reduce the level of urine output in the ABRT group without continuous exercise, demonstrating either intervention/treatment alone is effective, despite no additive effect. Although intake did not change from pre-injury levels despite polyuria, DDAVP treatment also reduced drink volume.Further studies are needed as the mechanisms underlying changes in fluid and solute balance are likely multi-factorial involving a complex interaction between the neural (both central and peripheral) control of systems mediating thirst, urinary output, and cardiovascular regulation.


Assuntos
Desamino Arginina Vasopressina , Traumatismos da Medula Espinal , Humanos , Criança , Masculino , Ratos , Animais , Desamino Arginina Vasopressina/farmacologia , Desamino Arginina Vasopressina/uso terapêutico , Poliúria/tratamento farmacológico , Poliúria/etiologia , Ratos Wistar , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/tratamento farmacológico , Micção
3.
Neurotrauma Rep ; 3(1): 190-198, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35558732

RESUMO

Spinal cord injury (SCI) significantly impacts many systems attributable to disrupted autonomic regulation of the body. Of these disruptions, excessive production/passage of urine (polyuria) has been understudied. Pre-clinical animal studies investigating SCI-induced polyuria have been carried out in T8-T10 spinal-level contusive injuries, which directly impacts both supraspinal sympathetic inputs to the spinal circuitry mediating kidney function as well as local networks including pre-ganglionic sympathetic fibers to the kidney. The current study utilizes a higher-level (T3) contusion to narrow the potential source(s) of damage that induce(s) polyuria. Metabolic cage 24-h urine collections demonstrated that, starting 1 week post-SCI and lasting chronically through 6 weeks post-SCI, T3 contused adult male rats had a significant increase in void volume relative to pre-injury and surgical sham controls. Subsequent examination of previously identified biomarkers revealed levels reflecting the presence of polyuria. For example, urine atrial natriuretic peptide levels were significantly increased at 6 weeks post-SCI compared to baseline, and serum arginine vasopressin (AVP) levels were significantly decreased. Further, there was a significant decrease post-injury relative to shams in the number of AVP-labeled cells within the suprachiasmatic nucleus, a hypothalamic region responsible for significant disruptions of circadian rhythmicity post-SCI, including loss of the diurnal variation of AVP production, which clinical studies have identified as contributing to the emergence of nocturia after SCI. Together, the current results demonstrate that SCI-induced polyuria is present after a T3-level SCI, indicating that damage of descending supraspinal circuitries precipitates dysfunction of homeostatic mechanisms involved in salt and water balance.

4.
Neurotrauma Rep ; 2(1): 462-475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901942

RESUMO

Deficits in upper and lower urinary tract function, which include detrusor overactivity, urinary incontinence, detrusor-sphincter dyssynergia, and polyuria, are among the leading issues that arise after spinal cord injury (SCI) affecting quality of life. Given that overproduction of urine (polyuria) has been shown to be associated with an imbalance in key regulators of body fluid homeostasis, the current study examined the timing of changes in levels of various relevant hormones, peptides, receptors, and channels post-contusion injury in adult male Wistar rats. The results show significant up- or downregulation at various time points, beginning at 7 days post-injury, in levels of urinary atrial natriuretic peptide, serum arginine vasopressin (AVP), kidney natriuretic peptide receptor-A, kidney vasopressin-2 receptor, kidney aquaporin-2 channels, and kidney epithelial sodium channels (ß- and γ-, but not α-, subunits). The number of AVP-labeled neurons in the hypothalamus (supraoptic and -chiasmatic, but not paraventricular, nuclei) was also significantly altered at one or more time points. These data show significant fluctuations in key biomarkers involved in body fluid homeostasis during the post-SCI secondary injury phase, suggesting that therapeutic interventions (e.g., desmopressin, a synthetic analogue of AVP) should be considered early post-SCI.

5.
J Neurotrauma ; 37(3): 555-563, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31456470

RESUMO

Complications in upper and lower urinary function arise after spinal cord injury (SCI), which creates a significant impact on quality of life for those affected. One upper urinary complication is SCI-induced polyuria, or the overproduction of urine, of which the underlying mechanisms have yet to be elucidated. Activity-based training (ABT) has been utilized in both animal and clinical settings as a rehabilitative therapy to improve many issues that arise after SCI, including more recently urogenital function. The goal of the current study was to identify potential mechanisms contributing to previously identified improvements in polyuria with ABT, using a male rat moderate-severe spinal contusion model. Although ABT had no significant effect on reversing injury-induced alterations of serum arginine vasopressin and urinary atrial natriuretic peptide levels, there was a dramatic effect upon the receptors of these fluid balance hormones (vasopressin receptor 2 and natriuretic peptide A receptor), as well as kidney aquaporin 2 and sodium channels. ABT changes in densities of key receptors and kidney membrane proteins involved in fluid balance after chronic SCI support the likelihood of multiple mechanisms through which exercise can positively influence urinary tract function after SCI. By understanding the mechanisms, amount, and timing regarding how ABT improves different aspects of urinary function, more targeted training strategies can be developed to optimize the functional gains within the SCI population.


Assuntos
Rim/metabolismo , Proteínas de Membrana/metabolismo , Condicionamento Físico Animal/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/metabolismo , Animais , Teste de Esforço/métodos , Teste de Esforço/tendências , Rim/fisiologia , Masculino , Condicionamento Físico Animal/métodos , Condicionamento Físico Animal/tendências , Ratos , Ratos Wistar , Traumatismos da Medula Espinal/fisiopatologia , Traumatismos da Medula Espinal/reabilitação , Vértebras Torácicas/lesões , Micção/fisiologia
6.
Cancer Epidemiol Biomarkers Prev ; 28(12): 2055-2061, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31501149

RESUMO

BACKGROUND: Multiple myeloma is a common hematologic malignancy consistently preceded by monoclonal gammopathy of undetermined significance (MGUS). Little is known about postdiagnosis clinical predictors of progression of MGUS to multiple myeloma to guide MGUS management. This study aimed to investigate whether the rate of rise in serum monoclonal protein concentration during the year after MGUS diagnosis-M-protein velocity-predicts progression of MGUS to multiple myeloma. METHODS: Data from the U.S. Veterans Health Administration system were used. A retrospective cohort of patients with MGUS who progressed to multiple myeloma were matched on age at MGUS diagnosis and race in a 1:4 ratio to the patients with MGUS using incidence density sampling. Kaplan-Meier curves were plotted. Univariable and multivariable conditional logistic regression analyses were fitted from the matched risk sets. RESULTS: A total of 128 cases and 490 matched controls were included. The case group contained a higher percentage of patients with M-protein velocity >0.1 g/dL/year than the control group (44.5% vs. 28.2%, P <0.0001). M-protein velocity of >0.1 g/dL during the year following MGUS diagnosis was positively associated with progression of MGUS to multiple myeloma (multivariable-adjusted odds ratio = 2.15; 95% confidence interval, 1.37-3.35). CONCLUSIONS: Patients with a positive M-protein velocity during the year after MGUS diagnosis may be considered for more frequent monitoring for early detection and timely treatment of multiple myeloma. Future prevention studies could target these patients for intervention evaluation. IMPACT: Our results suggest a new clinical predictor of progression to multiple myeloma following MGUS diagnosis, which has potential to identify high-risk patients for management and prevention.


Assuntos
Biomarcadores Tumorais/sangue , Gamopatia Monoclonal de Significância Indeterminada/complicações , Mieloma Múltiplo/sangue , Mieloma Múltiplo/patologia , Proteínas do Mieloma/análise , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Mieloma Múltiplo/etiologia , Prognóstico , Estudos Retrospectivos
7.
J Vis Exp ; (143)2019 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-30735203

RESUMO

Spinal cord injury (SCI) results in lasting deficits that include both mobility and a multitude of autonomic-related dysfunctions. Locomotor training (LT) on a treadmill is widely used as a rehabilitation tool in the SCI population with many benefits and improvements to daily life. We utilize this method of activity-based task-specific training (ABT) in rodents after SCI to both elucidate the mechanisms behind such improvements and to enhance and improve upon existing clinical rehabilitation protocols. Our current goal is to determine the mechanisms underlying ABT-induced improvements in urinary, bowel, and sexual function in SCI rats after a moderate to severe level of contusion. After securing each individual animal in a custom-made adjustable vest, they are secured to a versatile body weight support mechanism, lowered to a modified three-lane treadmill and assisted in step-training for 58 minutes, once a day for 10 weeks. This setup allows for the training of both quadrupedal and forelimb-only animals, alongside two different non-trained groups. Quadrupedal-trained animals with body weight support are aided by a technician present to assist in stepping with proper hind limb placement as necessary, while forelimb-only trained animals are raised at the caudal end to ensure no hind limb contact with the treadmill and no weight-bearing. One non-trained SCI group of animals is placed in a harness and rests next to the treadmill, while the other control SCI group remains in its home cage in the training room nearby. This paradigm allows for the training of multiple SCI animals at once, thus making it more time-efficient in addition to ensuring that our pre-clinical animal model mimics the clinical representation as close as possible, particularly with respect to the body weight support with manual assistance.


Assuntos
Condicionamento Físico Animal , Traumatismos da Medula Espinal/fisiopatologia , Anestesia , Animais , Peso Corporal , Feminino , Poliúria/etiologia , Ratos Wistar , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/complicações
9.
J Clin Oncol ; 34(33): 4008-4014, 2016 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-27646948

RESUMO

Purpose The 3-hydroxy-3-methylglutaryl-coenzyme A reductase inhibitors (statins) have activity in one of the pathways influenced by nitrogen-containing bisphosphonates, which are associated with improved survival in multiple myeloma (MM). To understand the benefit of statins in MM, we evaluated the association between statin use and mortality in a large cohort of patients with MM. Patients and Methods From the Veterans Administration Central Cancer Registry, we identified patients diagnosed with MM between 1999 and 2013. We defined statin use as the presence of any prescription for a statin within 3 months before or any time after MM diagnosis. Cox proportional hazards regression assessed the association of statin use with mortality, while controlling for known MM prognostic factors. Results We identified a cohort of 4,957 patients, of whom 2,294 received statin therapy. Statin use was associated with a 21% decrease in all-cause mortality (adjusted hazard ratio, 0.79; 95% CI, 0.73 to 0.86; P < .001) as well as a 24% decrease in MM-specific mortality (adjusted hazard ratio, 0.76; 95% CI, 0.67 to 0.86; P < .001). This association remained significant across all sensitivity analyses. In addition to reductions in mortality, statin use was associated with a 31% decreased risk of developing a skeletal-related event. Conclusion In this cohort study of US veterans with MM, statin therapy was associated with a reduced risk of both all-cause and MM-specific mortality. Our findings suggest a potential role for statin therapy in patients with MM. The putative benefit of statin therapy in MM should be corroborated in prospective studies.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Mieloma Múltiplo/mortalidade , Idoso , Feminino , Humanos , Masculino , Modelos de Riscos Proporcionais , Sistema de Registros , Estados Unidos/epidemiologia , United States Department of Veterans Affairs
10.
PLoS One ; 7(12): e52156, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23284914

RESUMO

The pituitary gland regulates numerous physiological functions including growth, reproduction, temperature and metabolic homeostasis, lactation, and response to stress. Pituitary organogenesis is dependent on signaling factors that are produced in and around the developing pituitary. The studies described in this report reveal that the forkhead transcription factor, Foxd1, is not expressed in the developing mouse pituitary gland, but rather in the mesenchyme surrounding the pituitary gland, which is an essential source of signaling factors that regulate pituitary organogenesis. Loss of Foxd1 causes a morphological defect in which the anterior lobe of the pituitary gland protrudes through the cartilage plate that is developing ventral to the pituitary at embryonic days (e)14.5, e16.5, and e18.5. The number of proliferating pituitary cells is increased at e14.5 and e16.5. Loss of Foxd1 also results in significantly decreased levels of Lhb expression at e18.5. This decrease in Lhb expression does not appear to be due to a change in the number of gonadotrope cells in the pituitary gland. Previous studies have shown that loss of the LIM homeodomain factor, Lhx3, which is activated by the FGF signaling pathway, results in loss of LH production. Although there is a difference in Lhb expression in Foxd1 null mice, the expression pattern of LHX3 is not altered in Foxd1 null mice. These studies suggest that Foxd1 is indirectly required for normal Lhb expression and cartilage formation.


Assuntos
Fatores de Transcrição Forkhead/metabolismo , Hormônio Luteinizante/metabolismo , Hipófise/metabolismo , Animais , Fatores de Transcrição Forkhead/genética , Imuno-Histoquímica , Proteínas com Homeodomínio LIM/genética , Proteínas com Homeodomínio LIM/metabolismo , Hormônio Luteinizante/genética , Camundongos , Camundongos Mutantes , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
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