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1.
Brain ; 2024 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-38808482

RESUMEN

Comprehensive understanding of the neural circuits involving the ventral tegmental area is essential for elucidating the anatomo-functional mechanisms governing human behaviour as well as the therapeutic and adverse effects of deep brain stimulation for neuropsychiatric diseases. While the ventral tegmental area has been successfully targeted with deep brain stimulation for different neuropsychiatric diseases, the axonal connectivity of the region has not been fully understood. Here using fiber micro-dissections in human cadaveric hemispheres, population-based high-definition fiber tractography, and previously reported deep brain stimulation hotspots, we find that the ventral tegmental area participates in an intricate network involving the serotonergic pontine nuclei, basal ganglia, limbic system, basal forebrain, and prefrontal cortex, which is implicated in the treatment of obsessive-compulsive disorder, major depressive disorder, Alzheimer's disease, cluster headaches, and aggressive behaviors.

2.
Hum Brain Mapp ; 45(3): e26630, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38376145

RESUMEN

The frontal aslant tract (FAT) is a crucial neural pathway of language and speech, but little is known about its connectivity and segmentation differences across populations. In this study, we investigate the probabilistic coverage of the FAT in a large sample of 1065 young adults. Our primary goal was to reveal individual variability and lateralization of FAT and its structure-function correlations in language processing. The study utilized diffusion MRI data from 1065 subjects obtained from the Human Connectome Project. Automated tractography using DSI Studio software was employed to map white matter bundles, and the results were examined to study the population variation of the FAT. Additionally, anatomical dissections were performed to validate the fiber tracking results. The tract-to-region connectome, based on Human Connectome Project-MMP parcellations, was utilized to provide population probability of the tract-to-region connections. Our results showed that the left anterior FAT exhibited the most substantial individual differences, particularly in the superior and middle frontal gyrus, with greater variability in the superior than the inferior region. Furthermore, we found left lateralization in FAT, with a greater difference in coverage in the inferior and posterior portions. Additionally, our analysis revealed a significant positive correlation between the left FAT inferior coverage area and the performance on the oral reading recognition (p = .016) and picture vocabulary (p = .0026) tests. In comparison, fractional anisotropy of the right FAT exhibited marginal significance in its correlation (p = .056) with Picture Vocabulary Test. Our findings, combined with the connectivity patterns of the FAT, allowed us to segment its structure into anterior and posterior segments. We found significant variability in FAT coverage among individuals, with left lateralization observed in both macroscopic shape measures and microscopic diffusion metrics. Our findings also suggested a potential link between the size of the left FAT's inferior coverage area and language function tests. These results enhance our understanding of the FAT's role in brain connectivity and its potential implications for language and executive functions.


Asunto(s)
Conectoma , Sustancia Blanca , Humanos , Adulto Joven , Imagen de Difusión Tensora , Encéfalo/diagnóstico por imagen , Lóbulo Frontal/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen , Lenguaje , Vías Nerviosas/diagnóstico por imagen
3.
Nutr Cancer ; 75(2): 552-561, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36272100

RESUMEN

BACKGROUND: Selenium (Se) is a trace element that has been investigated as a potential chemopreventive agent for colorectal cancer. Dietary intake of other antioxidant nutrients may modify the effect of Se. OBJECTIVE: We examined the association between intake and serum concentrations of retinol, ß-carotene, ß-cryptoxanthin, lycopene, lutein/zeaxanthin, and α- and γ-tocopherol and the development of metachronous colorectal adenoma, and if these nutrients modified the effect of Se. METHODS: We conducted a prospective study of 1874 participants from the Se Trial with data for antioxidant intake, as well as a subcohort of 508 participants with serum biomarker concentrations. RESULTS: Statistically significantly lower odds for the development of metachronous adenoma were observed for those participants in the highest tertile of intake for lutein/zeaxanthin compared to the lowest, with an OR (95% CI) of 0.72 (0.56-0.94). No effect modification for intake of any nutrient was observed. However, circulating concentrations of lycopene exhibited statistically significant effect modification of selenium supplementation (p < 0.06). CONCLUSION: These findings show that intake and circulating concentrations of antioxidant nutrients were not consistently associated with reduced odds for the development of metachronous lesions, although blood concentrations of lycopene may modify the effect of selenium supplementation.


Asunto(s)
Adenoma , Neoplasias Colorrectales , Selenio , Humanos , Antioxidantes/farmacología , Selenio/farmacología , Licopeno , Carotenoides/farmacología , Luteína , Estudios Prospectivos , Zeaxantinas , Factores de Riesgo , Neoplasias Colorrectales/prevención & control , Suplementos Dietéticos , Adenoma/prevención & control
4.
Am J Obstet Gynecol ; 228(5): 561.e1-561.e17, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36706857

RESUMEN

BACKGROUND: Systemic administration of soluble factors from bone marrow-derived stem cells combined with activated platelet-rich plasma (SC-PRP) restored ovarian function, mediated through paracrine signaling, in murine models of chemotherapy-induced ovarian damage and human tissue from poor responder patients. However, the effects against age-related infertility and the efficacy of local administration have not been evaluated yet. OBJECTIVE: This study aimed to assess whether a single intraovarian dose of stem cells combined with activated platelet-rich plasma can recover ovarian function, oocyte quality, and developmental competence in older mice. STUDY DESIGN: The effects of stem cells combined with activated platelet-rich plasma against age-related infertility were assessed following controlled ovarian stimulation in an aging murine model reproducing 3 physiological stages of women's reproductive life, namely young, advanced maternal age, and menopausal (n=12 animals per group). Female mice were randomized to receive a single intraovarian injection (10 µL/ovary) of either saline, activated platelet-rich plasma, or stem cells combined with activated platelet-rich plasma. Seven days later, the mice were stimulated, naturally mated, and sacrificed to harvest their ovaries for histologic assessment and molecular analysis and their oviducts to evaluate oocyte maturation and to assess early embryo development. RESULTS: A single intraovarian injection of stem cells combined with activated platelet-rich plasma promoted follicle activation and development in young, advanced maternal age, and old mice. Furthermore, stem cells combined with activated platelet-rich plasma rescued fertility in older mice by enhancing the quantity and quality of ovulated mature oocytes and supporting early embryo development to the blastocyst stage in all the evaluated ages. These fertility outcomes were positively associated with mitochondrial quality, treatment-increased mitochondrial DNA copy numbers, and reduced oxidative damage and apoptosis. Finally, the effects observed by histologic analysis were supported at the proteomic level. Functional proteomic analyses revealed molecular mechanisms involved in oocyte maturation and quality, mitochondrial function, and recovery of the ovarian stroma. CONCLUSION: Bone marrow-derived stem cells combined with activated platelet-rich plasma is a promising treatment with the potential to improve the reproductive outcomes of women with age-related infertility, exceeding the restorative effects of platelet-rich plasma alone. Although further research in human ovarian samples is still required, the autologous nature of stem cell factors collected by noninvasive mobilization, their combination with platelet-rich plasma, and the local administration route suggest that stem cells combined with activated platelet-rich plasma treatment could be a potentially effective and safe application for future clinical practice.


Asunto(s)
Infertilidad , Ovario , Animales , Femenino , Humanos , Ratones , Modelos Animales de Enfermedad , Oocitos , Proteómica , Células Madre , Distribución Aleatoria
5.
Brain Inj ; 37(7): 588-595, 2023 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-36867013

RESUMEN

BACKGROUND: Despite increased efforts directed toward research, concussions are a growing concern and can be a complex injury for healthcare professionals to manage. Current practices are largely dependent on patients self-reporting symptoms and a clinical assessment, which uses objective tools that lack effectiveness. With the demonstrated effects of concussions, it is imperative that a more valid or reliable objective tool, like a clinical biomarker, be identified to improve outcomes. One potential biomarker that has shown promise is salivary microRNA. However, there is no objective consensus as to which microRNA offers the most clinical value regarding concussions, hence this review. Therefore, the purpose of this scoping review was to identify salivary miRNAs associated with concussions. METHODS: Two independent reviewers performed a literature search to identify research articles. Studies using human subjects, collected salivary miRNA, and were published in English were included. Data of interest were salivary miRNA, collection timing, and relation to concussion diagnosis or management. RESULTS: This paper reviews nine studies that analyzed salivary miRNA for concussion diagnosis and management. CONCLUSIONS: In total, the studies have identified 49 salivary miRNA that show promise in assisting with concussion practices. With continued research, the use of salivary miRNA may enhance clinicians' abilities to diagnose and manage concussions.


Asunto(s)
Traumatismos en Atletas , Conmoción Encefálica , MicroARNs , Humanos , Traumatismos en Atletas/diagnóstico , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/terapia , Biomarcadores
6.
Entropy (Basel) ; 25(3)2023 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-36981383

RESUMEN

Chaotic systems are hard to synchronize, and no general solution exists. The presence of hidden attractors makes finding a solution particularly elusive. Successful synchronization critically depends on the control strategy, which must be carefully chosen considering system features such as the presence of hidden attractors. We studied the feasibility of fuzzy control for synchronizing chaotic systems with hidden attractors and employed a special numerical integration method that takes advantage of the oscillatory characteristic of chaotic systems. We hypothesized that fuzzy synchronization and the chosen numerical integration method can successfully deal with this case of synchronization. We tested two synchronization schemes: complete synchronization, which leverages linearization, and projective synchronization, capitalizing on parallel distributed compensation (PDC). We applied the proposal to a set of known chaotic systems of integer order with hidden attractors. Our results indicated that fuzzy control strategies combined with the special numerical integration method are effective tools to synchronize chaotic systems with hidden attractors. In addition, for projective synchronization, we propose a new strategy to optimize error convergence. Furthermore, we tested and compared different Takagi-Sugeno (T-S) fuzzy models obtained by tensor product (TP) model transformation. We found an effect of the fuzzy model of the chaotic system on the synchronization performance.

7.
Breast Cancer Res Treat ; 192(1): 113-122, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35039952

RESUMEN

PURPOSE: To examine benefit of sulindac for relief of musculoskeletal symptoms (MSS) in patients stable on aromatase inhibitors (AIs). METHODS: Sulindac was evaluated at 150 mg twice daily for effects on MSS at 3, 6, 9, and 12 months in 50 postmenopausal women stable on AI therapy for a median of 12.5 months for hormone receptor-positive breast cancer. A separate, non-randomized group of 50 similar patients was observed for change in MSS over 12 months. MSS severity was assessed using the Western Ontario and McMaster Universities Osteoarthritis (WOMAC) Index and Brief Pain Inventory Short Form (BPI-SF). The Functional Assessment of Cancer Therapy-General form (FACT-G) measured quality of life (QOL). Change in MSS and QOL across time was assessed in each group using linear mixed effects models. RESULTS: Stiffness, not pain, was the main complaint at baseline. At 12 months, sulindac patients reported decreases (improvements) in mean (95% CI) Total WOMAC score [- 5.85 (- 9.73, - 1.96)] and WOMAC pain [- 5.40 (- 10.64, - 0 .18)], Stiffness [- 9.53 (- 14.98, - 4.08)] and Physical Function [- 5.61 (- 9.62, - 1.60)] subscales, but not BPI-SF worst pain. Among sulindac patients with higher baseline MSS severity, 35% experienced ≥ 50% improvement in Total WOMAC and Total FACT-G scores [6.18 (2.08, 10.27); P = 0.003]. For the observation group, MSS and QOL did not improve over 12 months, even among those with higher baseline MSS severity. CONCLUSIONS: Sulindac may relieve MSS in AI patients, especially physical function and stiffness. Randomized controlled trials should further evaluate NSAIDs on AI-MSS and AI adherence. TRIAL REGISTRATION NUMBER AND DATE OF REGISTRATION: NCT01761877, December, 2012.


Asunto(s)
Inhibidores de la Aromatasa , Neoplasias de la Mama , Sulindac , Inhibidores de la Aromatasa/efectos adversos , Neoplasias de la Mama/tratamiento farmacológico , Femenino , Humanos , Dolor , Calidad de Vida , Sulindac/uso terapéutico , Resultado del Tratamiento
8.
J Invertebr Pathol ; 193: 107801, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35863438

RESUMEN

Nosema ceranae is a microsporidium parasite that silently affects honey bees, causing a disease called nosemosis. This parasite produces resistant spores and germinates in the midgut of honey bees, extrudes a polar tubule that injects an infective sporoplasm in the host cell epithelium, proliferates, and produces intestinal disorders that shorten honey bee lifespan. The rapid extension of this disease has been reported to be widespread among adult bees, and treatments are less effective and counterproductive weakening colonies. This work aimed to evaluate the antifungal activity of a prototype formulation based on a non-toxic plant extract (HO21-F) against N. ceranae. In laboratory, honey bees were infected artificially, kept in cages for 17 days and samples were taken at 7 and 14 days post infection (dpi). At the same time, in field conditions we evaluated the therapeutic effect of HO21-F for 28 days in naturally infected colonies. The effectiveness of the treatment has been demonstrated by a reduction of 83.6 % of the infection levels observed in laboratory conditions at concentrations of 0.5 and 1 g/L without affecting the survival rate. Besides, in-field conditions we reported a reduction of 88 % of the infection level at a concentration of 2.5 g/L, obtaining better antifungal effectiveness in comparison to other commercially available treatments. As a result, we observed that the use of HO21-F led to an increase in population size and honey production, both parameters associated with colony strength. The reported antifungal activity of HO21-F against N. ceranae, with a significant control of spore proliferation in worker bees, suggests the promising commercial application use of this product against nosemosis, and it will encourage new research studies to understand the mechanism of action, whether related to the spore-inhibition effect and/or a stimulating effect in natural response of colonies to counteract the disease.


Asunto(s)
Microsporidiosis , Nosema , Olea , Animales , Antifúngicos/farmacología , Abejas , Nosema/fisiología , Extractos Vegetales/farmacología
9.
Physiol Genomics ; 53(3): 85-98, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-33522389

RESUMEN

Radiation therapy for head and neck cancer causes damage to the surrounding salivary glands, resulting in salivary gland hypofunction and xerostomia. Current treatments do not provide lasting restoration of salivary gland function following radiation; therefore, a new mechanistic understanding of the radiation-induced damage response is necessary for identifying therapeutic targets. The purpose of the present study was to investigate the metabolic phenotype of radiation-induced damage in parotid salivary glands by integrating transcriptomic and metabolomic data. Integrated data were then analyzed to identify significant gene-metabolite interactions. Mice received a single 5 Gy dose of targeted head and neck radiation. Parotid tissue samples were collected 5 days following treatment for RNA sequencing and metabolomics analysis. Altered metabolites and transcripts significantly converged on a specific region in the metabolic reaction network. Both integrative pathway enrichment using rank-based statistics and network analysis highlighted significantly coordinated changes in glutathione metabolism, energy metabolism (TCA cycle and thermogenesis), peroxisomal lipid metabolism, and bile acid production with radiation. Integrated changes observed in energy metabolism suggest that radiation induces a mitochondrial dysfunction phenotype. These findings validated previous pathways involved in the radiation-damage response, such as altered energy metabolism, and identified robust signatures in salivary glands, such as reduced glutathione metabolism, that may be driving salivary gland dysfunction.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Neoplasias de Cabeza y Cuello/radioterapia , Metabolómica/métodos , Traumatismos Experimentales por Radiación/genética , Glándulas Salivales/efectos de la radiación , Animales , Redes Reguladoras de Genes/efectos de la radiación , Humanos , Ratones , Mapas de Interacción de Proteínas/genética , Mapas de Interacción de Proteínas/efectos de la radiación , Traumatismos Experimentales por Radiación/metabolismo , Glándulas Salivales/metabolismo , Glándulas Salivales/fisiopatología , Transducción de Señal/genética , Transducción de Señal/efectos de la radiación , Xerostomía/genética , Xerostomía/metabolismo , Xerostomía/fisiopatología
10.
Hum Brain Mapp ; 42(7): 2250-2261, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33559959

RESUMEN

It has been hypothesized that the human brain has less redundancy than animals, but the structural evidence has not been identified to confirm this claim. Here, we report three redundancy circuits of the commissural pathways in primate brains, namely the orbitofrontal, temporal, and occipital redundancy circuits of the anterior commissure and corpus callosum. Each redundancy circuit has two distinctly separated routes connecting a common pair of cortical regions. We mapped their trajectories in human and rhesus macaque brains using individual and population-averaged tractography. The dissection results confirmed the existence of these redundancy circuits connecting the orbitofrontal lobe, amygdala, and visual cortex. The volume analysis showed a significant reduction in the orbitofrontal and occipital redundancy circuits of the human brain, whereas the temporal redundancy circuit had a substantial organizational difference between the human and rhesus macaque. Our results support the hypothesis that the human brain has less redundancy in the commissural pathways than that of the rhesus macaque brain. Further studies are needed to explore its neuropathological implications.


Asunto(s)
Amígdala del Cerebelo/anatomía & histología , Corteza Cerebral/anatomía & histología , Cuerpo Calloso/anatomía & histología , Red Nerviosa/anatomía & histología , Sustancia Blanca/anatomía & histología , Adulto , Amígdala del Cerebelo/diagnóstico por imagen , Animales , Cadáver , Corteza Cerebral/diagnóstico por imagen , Cuerpo Calloso/diagnóstico por imagen , Imagen de Difusión Tensora , Femenino , Humanos , Macaca mulatta , Masculino , Red Nerviosa/diagnóstico por imagen , Vías Nerviosas/anatomía & histología , Vías Nerviosas/diagnóstico por imagen , Sustancia Blanca/diagnóstico por imagen
11.
Breast Cancer Res Treat ; 190(1): 69-78, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34383179

RESUMEN

PURPOSE: Obesity is a known risk factor for post-menopausal breast cancer and may increase risk for triple negative breast cancer in premenopausal women. Intervention strategies are clearly needed to reduce obesity-associated breast cancer risk. METHODS: We conducted a Phase II double-blind, randomized, placebo-controlled trial of metformin in overweight/obese premenopausal women with components of metabolic syndrome to assess the potential of metformin for primary breast cancer prevention. Eligible participants were randomized to receive metformin (850 mg BID, n = 76) or placebo (n = 75) for 12 months. Outcomes included breast density, assessed by fat/water MRI with change in percent breast density as the primary endpoint, anthropometric measures, and intervention feasibility. RESULTS: Seventy-six percent in the metformin arm and 83% in the placebo arm (p = 0.182) completed the 12-month intervention. Adherence to study agent was high with more than 80% of participants taking ≥ 80% assigned pills. The most common adverse events reported in the metformin arm were gastrointestinal in nature and subsided over time. Compared to placebo, metformin intervention led to a significant reduction in waist circumference (p < 0.001) and waist-to-hip ratio (p = 0.019). Compared to placebo, metformin did not change percent breast density and dense breast volume but led to a numerical but not significant decrease in non-dense breast volume (p = 0.070). CONCLUSION: We conclude that metformin intervention resulted in favorable changes in anthropometric measures of adiposity and a borderline decrease in non-dense breast volume in women with metabolic dysregulation. More research is needed to understand the impact of metformin on breast cancer risk reduction. TRIAL REGISTRATION: ClinicalTrials.gov NCT02028221. Registered January 7, 2014, https://clinicaltrials.gov/ct2/show/NCT02028221.


Asunto(s)
Neoplasias de la Mama , Síndrome Metabólico , Metformina , Adiposidad , Densidad de la Mama , Neoplasias de la Mama/complicaciones , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/epidemiología , Estudios de Factibilidad , Femenino , Humanos , Mamografía , Síndrome Metabólico/complicaciones , Síndrome Metabólico/tratamiento farmacológico , Síndrome Metabólico/epidemiología , Metformina/efectos adversos , Obesidad/complicaciones , Obesidad/tratamiento farmacológico
12.
J Gen Intern Med ; 36(9): 2739-2744, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33145693

RESUMEN

Recent mandates to wear masks in public places across the USA combined with conflicting messaging from the media and government agencies have generated a lot of patient questions surrounding the appropriate use and efficacy of cloth masks. Here, we have organized the evidence in the context of real patient questions and have provided example answers from a physician's perspective. The purpose of this review is to offer healthcare providers with examples of how to respond to patient questions about masks in a way that encourages responsible decision-making. We conclude, based on the evidence showing a benefit for cloth masks and the recent reports supporting a role for aerosols in the transmission of SARS-CoV-2, that cloth masks will be effective when used correctly. We further assert that stronger public messaging surrounding cloth masks in the community setting is needed, and should specify that 2-3 layer, fitted face masks be worn at all times in public as another layer of protection in addition to social distancing, not just when social distancing cannot be maintained.


Asunto(s)
COVID-19 , Control de Enfermedades Transmisibles/métodos , Comunicación , Máscaras , Médicos , COVID-19/prevención & control , Control de Enfermedades Transmisibles/normas , Humanos
13.
Am J Obstet Gynecol ; 225(1): 65.e1-65.e14, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33539826

RESUMEN

BACKGROUND: Ovarian senescence is a normal age-associated phenomenon, but increasingly younger women are affected by diminished ovarian reserves or premature ovarian insufficiency. There is an urgent need for developing therapies to improve ovarian function in these patients. In this context, previous studies suggest that stem cell-secreted factors could have regenerative properties in the ovaries. OBJECTIVE: This study aimed to test the ability of various human plasma sources, enriched in stem cell-secreted factors, and the mechanisms behind their regenerative properties, to repair ovarian damage and to promote follicular development. STUDY DESIGN: In the first phase, the effects of human plasma enriched in bone marrow stem cell soluble factors by granulocyte colony-stimulating factor mobilization, umbilical cord blood plasma, and their activated forms on ovarian niche, follicle development, and breeding performance were assessed in mouse models of chemotherapy-induced ovarian damage (n=7 per group). In addition, the proteomic profile of each plasma was analyzed to find putative proteins and mechanism involved in their regenerative properties in ovarian tissue. In the second phase, the most effective plasma treatment was validated in human ovarian cortex xenografted in immunodeficient mice (n=4 per group). RESULTS: Infusion of human plasma enriched bone marrow stem cell soluble factors by granulocyte colony-stimulating factor mobilization or of umbilical cord blood plasma-induced varying degrees of microvessel formation and cell proliferation and reduced apoptosis in ovarian tissue to rescue follicular development and fertility in mouse models of ovarian damage. Plasma activation enhanced these effects. Activated granulocyte colony-stimulating factor plasma was the most potent inducing ovarian rescue in both mice and human ovaries, and proteomic analysis indicated that its effects may be mediated by soluble factors related to cell cycle and apoptosis, gene expression, signal transduction, cell communication, response to stress, and DNA repair of double-strand breaks, the most common form of age-induced damage in oocytes. CONCLUSION: Our findings suggested that stem cell-secreted factors present in both granulocyte colony-stimulating factor-mobilized and umbilical cord blood plasma could be an effective treatment for increasing the reproductive outcomes in women with impaired ovarian function owing to several causes. The activated granulocyte colony-stimulating factor plasma, which is already enriched in both stem cell-secreted factors and platelet-enclosed growth factors, seems to be the most promising treatment because of its most potent restorative effects on the ovary together with the autologous source.


Asunto(s)
Factores de Crecimiento de Célula Hematopoyética/uso terapéutico , Folículo Ovárico/efectos de los fármacos , Reserva Ovárica/efectos de los fármacos , Ovario/efectos de los fármacos , Insuficiencia Ovárica Primaria/tratamiento farmacológico , Células Madre/metabolismo , Animales , Células de la Médula Ósea , Modelos Animales de Enfermedad , Femenino , Sangre Fetal , Factor Estimulante de Colonias de Granulocitos/farmacología , Factores de Crecimiento de Célula Hematopoyética/farmacología , Xenoinjertos , Humanos , Recién Nacido , Ratones , Ratones Endogámicos NOD , Folículo Ovárico/crecimiento & desarrollo , Ovario/trasplante , Plasma/química , Factor de Células Madre/farmacología
14.
J Magn Reson Imaging ; 52(1): 91-102, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31922311

RESUMEN

BACKGROUND: MRI exams for patients with MR-conditional active implantable medical devices (AIMDs) are contraindicated unless specific conditions are met. This limits the maximum specific absorption rate (SAR, W/kg). Currently, there is no general framework to guide meeting a lower SAR limit. PURPOSE: To design and evaluate a workflow for modifying MRI protocols to whole-body SAR (WB-SAR ≤0.1 W/kg) and local-head SAR (LH-SAR ≤0.3 W/kg) limits while mitigating the impact on image quality and exam time. STUDY TYPE: Prospective. POPULATION: Twenty healthy volunteers on head (n = 5), C-spine (n = 5), T-spine (n = 5), and L-spine (n = 5) with IRB consent. ASSESSMENT: Vendor-provided head, C-spine, T-spine, and L-spine protocols (SARRT ) were modified to meet both low SAR targets (SARLOW ) using the proposed workflow. in vitro SNR and CNR were evaluated with a T1 -T2 phantom. in vivo image quality and clinical acceptability were scored using a 5-point Likert scale for two blinded readers. FIELD STRENGTH/SEQUENCES: 1.5T/spin-echoes, gradient-echoes. STATISTICAL ANALYSIS: In vitro SNR and CNR values were evaluated with a repeated measures general linear model. in vivo image quality and clinical acceptability were evaluated using a generalized estimating equation analysis (GEE). The two reader's level of agreement was analyzed using Cohen's kappa statistical analysis. RESULTS: Using the workflow, SAR limits were met. LH-SAR: 0.12 ± 0.02 W/kg, median (SD) values for LH-SAR were 0.12 (0.02) W/kg and WB-SAR: 0.09 (0.01) W/kg. Examination time did not increase ≤2x the initial time. SARRT SNR values were higher and significantly different than SARLOW (P < 0.05). However, no significant difference was observed between the CNR values (value = 0.21). Median (IQR) CNR values were 14.2 (25.0) vs. 15.1 (9.2) for head, 12.1 (16.9) vs. 25.3 (14.2) for C-spine, 81.6 (70.1) vs. 71.0 (26.6) for T-spine, and 51.4 (52.6) vs. 37.7 (27.3) for L-spine. Image quality scores were not significantly different between SARRT and SARLOW (median [SD] scores were 4.0 [0.01] vs. 4.3 [0.2], P > 0.05). DATA CONCLUSION: The proposed workflow provides guidance for modifying routine MRI exams to achieve low SAR limits. This can benefit patients referred for an MRI exam with low SAR MR-conditional AIMDs. LEVEL OF EVIDENCE: 1 Technical Efficacy Stage: 5 J. Magn. Reson. Imaging 2020;52:91-102.


Asunto(s)
Imagen por Resonancia Magnética , Prótesis e Implantes , Humanos , Fantasmas de Imagen , Estudios Prospectivos , Flujo de Trabajo
15.
Gac Med Mex ; 156(Suppl 1): S1-S45, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33103663

RESUMEN

To identify this increasingly common pathology, known as multiple myeloma (MM), it is necessary to refer to the specific factors that characterize it; to this end, the classic criteria known as CRAB (hyperkalemia, renal failure, anemia, and lytic lesions) are available, in which renal failure is one of the most frequent complications. Recently, three indisputable biomarkers have been described for the diagnostic support for MM, which are: more than 10% of clonal plasma cells in bone marrow or, a biopsy that corroborates the presence of a plasmacytoma, light chain ratio ≥ 100 mg/dL and more than one focal lesion on magnetic resonance imaging. A differential diagnosis for plasma cell leukemia, solitary bone plasmacytoma, and extramedullary plasmacytoma should always be considered. Being this an incurable disease, a lot of research has been done regarding its therapeutic management, whose main objective is the disappearance of plasma cells and the patient clinical improvement. Melphalan was the first drug that showed a benefit in 1958 and afterward, with the addition of a steroid as a second drug, it was possible to improve response rates. Subsequently, different molecules were studied, forming multiple combinations, and achieving better rates of overall survival and progression-free survival. Years later, with the arrival of proteasome inhibitors such as bortezomib, and immunomodulators such as thalidomide and lenalidomide, an important turnaround in the disease has been seen, as deeper responses, more prolonged remissions, and improvement in the quality of life of patients have been achieved. This consensus has the purpose of integrating a group of Mexican specialists and promoting the updating of this pathology.


Para identificar una patología cada vez más común, conocida como mieloma múltiple, es necesario hacer alusión de los factores específicos que la caracterizan. Para ello existen los clásicos criterios conocidos como CRAB (hipercalcemia, insuficiencia renal, anemia y lesiones líticas), siendo la insuficiencia renal una de sus complicaciones más frecuentes. Recientemente se han descrito tres biomarcadores indiscutibles para el apoyo diagnóstico del mieloma múltiple, que son: más del 10% de células plasmáticas clonales en medula ósea o biopsia que corrobora la presencia de un plasmocitoma, relación de cadenas ligeras ≥ 100 mg/dl y más de una lesión focal en resonancia magnética. Se debe tomar siempre en cuenta el diagnóstico diferencial con leucemia de células plasmáticas, plasmocitoma óseo solitario y plasmocitoma extramedular. Al ser una enfermedad incurable, se ha investigado mucho en cuanto al manejo terapéutico, el cual tiene como objetivo principal la desaparición de las células plasmáticas y la mejoría clínica del paciente. El primer fármaco que demostró algún beneficio fue el melfalán en el año 1958 y posteriormente al adicionar un esteroide como segundo fármaco se logró mejorar las tasas de respuesta. Después se fueron estudiando diferentes moléculas, con las que se han realizado múltiples combinaciones, alcanzando mejores tasas de supervivencia global y supervivencia libre de progresión. Años más tarde, con la llegada de los inhibidores de proteosoma como el bortezomib, así como de los agentes inmunomoduladores como la talidomida y la lenalidomida, se presenta un giro importante en la enfermedad, ya que se logran respuestas más profundas, periodo de remisiones más prolongadas y mejoría en la calidad de vida de los pacientes. Este consenso tiene la finalidad de integrar a un grupo de especialistas mexicanos y promover la actualización de esta patología.


Asunto(s)
Mieloma Múltiple/diagnóstico , Mieloma Múltiple/terapia , Algoritmos , Humanos , México , Mieloma Múltiple/complicaciones
16.
Neuroimage ; 195: 272-284, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-30935911

RESUMEN

Neurological disorders are increasingly analysed and treated with implantable electrodes, and patients with such electrodes are studied with MRI despite the risk of radio-frequency (RF) induced heating during the MRI exam. Recent clinical research suggests that electrodes with smaller diameters of the electrical interface between implant and tissue are beneficial; however, the influence of this electrode contact diameter on RF-induced heating has not been investigated. In this work, electrode contact diameters between 0.3 and 4 mm of implantable electrodes appropriate for stimulation and electrocorticography were evaluated in a 1.5 T MRI system. In situ temperature measurements adapted from the ASTM standard test method were performed and complemented by simulations of the specific absorption rate (SAR) to assess local SAR values, temperature increase and the distribution of dissipated power. Measurements showed temperature changes between 0.8 K and 53 K for different electrode contact diameters, which is well above the legal limit of 1 K. Systematic errors in the temperature measurements are to be expected, as the temperature sensors may disturb the heating pattern near small electrodes. Compared to large electrodes, simulations suggest that small electrodes are subject to less dissipated power, but more localized power density. Thus, smaller electrodes might be classified as safe in current certification procedures but may be more likely to burn adjacent tissue. To assess these local heating phenomena, smaller temperature sensors or new non-invasive temperature sensing methods are needed.


Asunto(s)
Electrodos Implantados , Calor , Imagen por Resonancia Magnética , Humanos
17.
Neuroimage ; 202: 116131, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31472253

RESUMEN

Diffusion MRI tractography has been used to map the axonal structure of the human brain, but its ability to detect neuronal injury is yet to be explored. Here we report differential tractography, a new type of tractography that utilizes repeat MRI scans and a novel tracking strategy to map the exact segment of fiber pathways with a neuronal injury. We examined differential tractography on multiple sclerosis, Huntington's disease, amyotrophic lateral sclerosis, and epileptic patients. The results showed that the affected pathways shown by differential tractography matched well with the unique clinical symptoms of the patients, and the false discovery rate of the findings could be estimated using a sham setting to provide a reliability measurement. This novel approach enables a quantitative and objective method to monitor neuronal injury in individuals, allowing for diagnostic and prognostic evaluation of brain diseases.


Asunto(s)
Esclerosis Amiotrófica Lateral/diagnóstico por imagen , Imagen de Difusión Tensora/normas , Epilepsia/diagnóstico por imagen , Enfermedad de Huntington/diagnóstico por imagen , Esclerosis Múltiple/diagnóstico por imagen , Neuronas/patología , Adulto , Esclerosis Amiotrófica Lateral/fisiopatología , Biomarcadores , Epilepsia/fisiopatología , Femenino , Humanos , Enfermedad de Huntington/fisiopatología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/fisiopatología , Adulto Joven
18.
Radiographics ; 39(6): 1611-1628, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31589585

RESUMEN

Cerebral venous thrombosis (CVT) is uncommon, representing approximately 0.5% of all cases of cerebrovascular disease worldwide. Many factors, alone or combined, can cause CVT. Although CVT can occur at any age, it most commonly affects neonates and young adults. CVT is difficult to diagnose clinically because patients can present with a wide spectrum of nonspecific manifestations, the most common of which are headache in 89%-91%, focal deficits in 52%-68%, and seizures in 39%-44% of patients. Consequently, imaging is fundamental to its diagnosis. MRI is the most sensitive and specific technique for diagnosis of CVT. The different MRI sequences, with and without the use of contrast material, have variable strengths. Contrast material-enhanced MR venography has the highest accuracy compared with sequences without contrast enhancement.Online supplemental material is available for this article.©RSNA, 2019.


Asunto(s)
Trombosis Intracraneal/diagnóstico por imagen , Imagen por Resonancia Magnética , Neuroimagen , Trombosis de la Vena/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Niño , Femenino , Humanos , Lactante , Recién Nacido , Trombosis Intracraneal/clasificación , Trombosis Intracraneal/diagnóstico , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neuroimagen/métodos , Trombosis de la Vena/clasificación , Trombosis de la Vena/diagnóstico , Adulto Joven
19.
Public Health Nutr ; 22(3): 542-552, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30451147

RESUMEN

OBJECTIVE: To assess the feasibility and acceptability of a beverage intervention in Hispanic adults. DESIGN: Eligible individuals identified as Hispanic, were 18-64 years old and had BMI 30·0-50·0 kg/m2. Participants were randomized 2:2:1 to one of three beverages: Mediterranean lemonade (ML), green tea (GT) or flavoured water control (FW). After a 2-week washout period, participants were asked to consume 32 oz (946 ml) of study beverage daily for 6 weeks and avoid other sources of tea, citrus, juice and sweetened beverages; water was permissible. Fasting blood samples were collected at baseline and 8 weeks to assess primary and secondary efficacy outcomes. SETTING: Tucson, AZ, USA.ParticipantsFifty-two participants were recruited over 6 months; fifty were randomized (twenty-one ML, nineteen GT, ten FW). Study population mean (sd) age 44·6 (sd 10·2) years, BMI 35·9 (4·6) kg/m2; 78 % female. RESULTS: Forty-four (88 %) completed the 8-week assessment. Self-reported adherence was high. No significant change (95 % CI) in total cholesterol (mg/dl) from baseline was shown -1·7 (-14·2, 10·9), -3·9 (-17·2, 9·4) and -13·2 (-30·2, 3·8) for ML, GT and FW, respectively. Mean change in HDL-cholesterol (mg/dl) -2·3 (-5·3, 0·7; ML), -1·0 (-4·2, 2·2; GT), -3·9 (-8·0, 0·2; FW) and LDL-cholesterol (mg/dl) 0·2 (-11·3, 11·8; ML), 0·5 (-11·4, 12·4; GT), -9·8 (-25·0, 5·4; FW) were also non-significant. Fasting glucose (mg/dl) increased significantly by 5·2 (2·6, 7·9; ML) and 3·3 (0·58, 6·4; GT). No significant change in HbA1c was demonstrated. Due to the small sample size, potential confounders and effect modifiers were not investigated. CONCLUSIONS: Recruitment and retention figures indicate that a larger-scale trial is feasible; however, favourable changes in cardiometabolic biomarkers were not demonstrated.


Asunto(s)
Bebidas , Promoción de la Salud/métodos , Hispánicos o Latinos , Adolescente , Adulto , Glucemia/análisis , Colesterol/sangre , Estudios de Factibilidad , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , , Adulto Joven
20.
Biol Reprod ; 99(2): 326-335, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29518247

RESUMEN

To analyze the role of PAI-1 (plasminogen activator inhibitor 1) in endometriotic lesion growth, we studied the effect of PAI-1 inhibition by PAI-039 using a homologous mouse model of endometriosis that allows noninvasive monitoring. Endometrial tissue from donor mice was collected, labeled with mCherry adenovirus, and implanted into a subcutaneous pocket on the ventral abdomen of recipient mice. Seven days after transplantation, mice were randomly allocated in two groups and treated once daily for 2 weeks with either vehicle (control group) or PAI-1 inhibitor (PAI-039 group). Endometriotic lesion size generated in recipient mice was monitored by mCherry signal. Animals were euthanized 21 days after endometrial tissue implantation and endometriotic lesions were harvested for fibrin deposit and vascularization analyses. Collagen content was also examined to determine the overall effects of proteolysis on extracellular matrix degradation. We demonstrated that endometriotic lesions generated in recipient mice from both groups presented characteristics typical of human endometriotic lesions. We observed a significant decrease in fluorescence signal in endometriotic lesions from the PAI-039 group at the beginning of the treatment correlated with a decrease in endometriotic lesion size. PAI-1 inhibition significantly decreased lesion cell proliferation. In addition, endometriotic lesions from the PAI-1 inhibition group showed a decreased percentage of neovascularization as well as fibrin deposits. However, the density and distribution of collagen were not affected by PAI-039. Our results suggest that in vivo inhibition of PAI-1 by PAI-039 may be a useful strategy to reduce endometriotic lesion size by blocking angiogenesis.


Asunto(s)
Endometriosis/metabolismo , Endometrio/metabolismo , Neovascularización Patológica/metabolismo , Serpina E2/metabolismo , Animales , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Endometrio/efectos de los fármacos , Femenino , Ácidos Indolacéticos/farmacología , Ratones , Serpina E2/antagonistas & inhibidores
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