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Despite most studies on the neurobiology of language demonstrating the central part of the perisylvian network involved in language and speech function, this review attempts to complement this view by focusing on the role of the orbitofrontal cortex (OFC). This region is primarily involved in goal-directed adaptive behavior. Recently, there has been increasing evidence that the OFC is involved in language and speech tasks. This review demonstrates that not only the linguistic tasks that involve the processing of socially, pragmatically and emotionally relevant information engage OFC and its neurobiological mechanisms, but also specific receptive and expressive language performances rely on specific neurophysiological properties of this region (e.g., the gray matter volume and the functional activation of OFC and the uncinate fasciculus that connects OFC), which in many cases, demand executive functions. These findings highlight: (1) The OFC plays a relevant role in the adaptive neurobiological function of language; (2) the neurobiological mechanisms beyond linguistic and speech processes complement and interplay with the language-unique processes to achieve successful comprehension and production in the changing communicative contexts.
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OBJECTIVE: This study used converging methods to examine the neural substrates of cognitive ability in middle-aged and older men with well-controlled HIV infection. METHODS: Seventy-six HIV+ men on antiretroviral treatment completed an auditory oddball task and an inhibitory control (Simon) task while time-locked high-density EEG was acquired; 66 had usable EEG data from one or both tasks; structural MRI was available for 43. We investigated relationships between task-evoked EEG responses, cognitive ability and immunocompromise. We also explored the structural correlates of these EEG markers in the sub-sample with complete EEG and MRI data (N = 27). RESULTS: EEG activity was associated with cognitive ability at later (P300) but not earlier stages of both tasks. Only the oddball task P300 was reliably associated with HIV severity (nadir CD4). Source localization confirmed that the tasks engaged partially distinct circuits. Thalamus volume correlated with oddball task P300 amplitude, while globus pallidus volume was related to the P300 in both tasks. INTERPRETATION: This is the first study to use task-evoked EEG to identify neural correlates of individual differences in cognition in men living with well-controlled HIV infection, and to explore the structural basis of the EEG markers. We found that EEG responses evoked by the oddball task are more reliably related to cognitive performance than those evoked by the Simon task. We also provide preliminary evidence for a subcortical contribution to the effects of HIV infection severity on P300 amplitudes. These results suggest brain mechanisms and candidate biomarkers for individual differences in cognition in HIV.
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Cognición , Infecciones por VIH/diagnóstico por imagen , Infecciones por VIH/fisiopatología , Imagen por Resonancia Magnética , Neuroimagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
OBJECTIVE: The objective of this study is to investigate whether cerebral small vessel disease (CSVD) is more common in virologically suppressed HIV-positive participants compared with HIV-negative controls and examine the potential synergistic effects of HIV and CSVD on brain structure and cognition. DESIGN: Cross-sectional analysis of 119 treated, virologically suppressed HIV-positive and 55 HIV-negative participants. Forty-six HIV-positive and 30 HIV-negative participants had follow-up 2 years later. All participants underwent MRI and neuropsychological testing. METHODS: Volume of white matter hyperintensities (WMH) was used as a surrogate measure of CSVD severity. Tensor-based morphometry and cortical modeling estimated brain volumes and cortical thickness, respectively. Rasch measurement theory was applied to neuropsychological test scores to estimate overall cognition. Linear models compared WMH loads, brain volumes, and cognition between groups; evaluated the association of WMH loads with brain volumes and cognition; and tested the interaction between HIV and WMH loads on brain volumes and cognition. Mixed-effects models compared the change in WMH loads between groups. RESULTS: WMH loads and change in WMH loads were similar between the groups. HIV-positive participants had poorer cognition, thinner cortex and reduced subcortical volumes compared with HIV-negative controls. Higher WMH loads were associated with reduced cortical thickness and subcortical volumes and worse cognition, regardless of HIV serostatus. No significant interactions were observed between HIV and WMH loads with regards to brain volumes or cognition. CONCLUSION: These findings suggest that the contributions of HIV and CSVD on brain atrophy and cognitive impairment are independent but additive processes. This argues that optimizing vascular health may mitigate brain injury and cognitive decline, especially in treated, virologically suppressed HIV-positive individuals.
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Enfermedades de los Pequeños Vasos Cerebrales/patología , Disfunción Cognitiva/patología , Infecciones por VIH/patología , Sustancia Blanca/patología , Anciano , Atrofia , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico por imagen , Enfermedades de los Pequeños Vasos Cerebrales/virología , Cognición , Disfunción Cognitiva/diagnóstico por imagen , Disfunción Cognitiva/virología , Estudios Transversales , Femenino , Infecciones por VIH/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/virologíaRESUMEN
Dielectric spectroscopy (biocapacitance) is an up-and-coming technology for real time monitoring of biomass in cell culture processes and has opened the door for next-generation cell culture process control techniques such as automated on-demand nutrient feeding. In this case study we empirically demonstrate the lower limit of quantitation (LOQ), probe-to-probe consistency, and scalability of in situ biocapacitance probes using data generated from small- and large-scale Chinese hamster ovary (CHO) bioreactor cultures. The process understanding experiments culminated in the use of biocapacitance for process control in the current good manufacturing practices (GMP) manufacturing environment, first to automate the dilution of seed train cultures during scale-up stages and later as a method of predicting future glucose demand. The automated biomass-probe-based inoculation strategy yielded consistent results in six consecutive seed trains in the GMP manufacturing suite. In the process of improving our understanding of the technology we determined that biocapacitance could additionally be used as an indicator of a shift in the salt balance of a cell culture, and that collecting real time biomass data via biocapacitance has the potential to reduce the total timeline for feed strategy development by providing additional insights into culture performance which are not otherwise apparent using conventional optical cell counting methods.
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Células CHO/metabolismo , Técnicas de Cultivo de Célula/métodos , Espectroscopía Dieléctrica/métodos , Animales , Biomasa , Reactores Biológicos , Células CHO/citología , Técnicas de Cultivo de Célula/instrumentación , Proliferación Celular , Cricetinae , Cricetulus , Medios de Cultivo/metabolismo , Glucosa/metabolismoRESUMEN
In spoken language, verbal cues (what we say) and vocal cues (how we say it) contribute to person perception, the process for interpreting information and making inferences about other people. When someone has an accent, forming impressions from the speaker's voice may be influenced by social categorization processes (i.e., activating stereotypical traits of members of a perceived 'out-group') and by processes which differentiate the speaker based on their individual attributes (e.g., registering the vocal confidence level of the speaker in order to make a trust decision). The neural systems for using vocal cues that refer to the speaker's identity and to qualities of their vocal expression to generate inferences about others are not known. Here, we used functional magnetic resonance imaging (fMRI) to investigate how speaker categorization influences brain activity as Canadian-English listeners judged whether they believe statements produced by in-group (native) and out-group (regional, foreign) speakers. Each statement was expressed in a confident, doubtful, and neutral tone of voice. In-group speakers were perceived as more believable than speakers with out-group accents overall, confirming social categorization of speakers based on their accent. Superior parietal and middle temporal regions were uniquely activated when listening to out-group compared to in-group speakers suggesting that they may be involved in extracting the attributes of speaker believability from the lower-level acoustic variations. Basal ganglia, left cuneus and right fusiform gyrus were activated by confident expressions produced by out-group speakers. These regions appear to participate in abstracting more ambiguous believability attributes from accented speakers (where a conflict arises between the tendency to disbelieve an out-group speaker and the tendency to believe a confident voice). For out-group speakers, stronger impressions of believability selectively modulated activity in the bilateral superior and middle temporal regions. Moreover, the right superior temporal gyrus, a region that was associated with perceived speaker confidence, was found to be functionally connected to the left lingual gyrus and right middle temporal gyrus when out-group speakers were judged as more believable. These findings suggest that identity-related voice characteristics and associated biases may influence underlying neural activities for making social attributions about out-group speakers, affecting decisions about believability and trust. Specifically, inferences about out-group speakers seem to be mediated to a greater extent by stimulus-related features (i.e., vocal confidence cues) than for in-group speakers. Our approach highlights how the voice can be studied to advance models of person perception.
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Ganglios Basales/fisiología , Corteza Cerebral/fisiología , Conectoma/métodos , Percepción Social , Percepción del Habla/fisiología , Adolescente , Adulto , Ganglios Basales/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Confianza , Adulto JovenRESUMEN
Fenestrated endovascular aneurysm repair (FEVAR) is a minimally invasive method of abdominal aortic aneurysm (AAA) repair utilized in patients with complex vessel anatomies. Stent grafts (SG) used in this process contain fenestrations within the device that need to be aligned with the visceral arteries upon successful SG deployment. Proper alignment is crucial to maintain blood flow to these arteries and avoid surgical complications. During fenestrated SG deployment, rotation of the SG can occur during the unsheathing process. This leads to misalignment of the vessels, and the fenestrations and is associated with poor clinical outcomes. The aim of this study was to develop a computational model of the FEVAR process to predict SG rotation. Six patient-specific cases are presented and compared with surgical case data. Realistic material properties, frictional effects, deployment methods, and boundary conditions are included in the model. A mean simulation error of 2 deg (range 1-4 deg) was observed. This model was then used to conduct a parameter study of frictional properties to see if rotation could be minimized. This study showed that increasing or decreasing the coefficients of friction (COF) between the sheath and the vessel walls would decrease the amount of rotation observed. Our model accurately predicts the amount of SG rotation observed during FEVAR and can be used as a preoperative planning tool within the surgical workflow.
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Aneurisma de la Aorta Abdominal/cirugía , Procedimientos Endovasculares , Análisis de Elementos Finitos , Rotación , Anciano , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Fenómenos Biomecánicos , Prótesis Vascular , Femenino , Humanos , Masculino , Tomografía Computarizada por Rayos XRESUMEN
Background: Human immunodeficiency virus (HIV) penetrates the brain in early infection. We used neuroimaging to longitudinally examine the impact of HIV and combination antiretroviral therapy (cART) on the brain in treated and untreated HIV-infected participants, starting in primary HIV infection (PHI). Methods: Sixty-five participants, enrolled during PHI, underwent longitudinal magnetic resonance imaging, 30 of whom commenced cART during follow-up. Cross-sectional data from 16 patients with chronic HIV infection (CHI) and 19 HIV-uninfected participants were included for comparison. Brain volume and cortical thickness were estimated using tensor-based morphometry and cortical modeling, respectively. Mixed-effects models longitudinally mapped structural brain changes before and after cART. The relationship between brain morphometry estimates and blood and cerebrospinal fluid (CSF) biomarkers were also tested. Region-of-interest analyses were performed to compare brain morphometry estimates between the groups. Results: Prior to cART, longer duration of untreated infection in PHI correlated with volume loss in the thalamus, caudate, and cerebellum, and with cortical thinning in the frontal and temporal lobes and cingulate cortex. After cART, no further volume loss was observed. However, small increases of cortical thickness in the frontal and temporal lobe correlated with longer cART duration. No correlations were observed with blood or CSF measures. The PHI group did not have different brain morphometric measures compared to the HIV-uninfected group, but had larger volumes in the thalamus, caudate, putamen, and cortical gray matter compared with CHI participants. Conclusions: Subcortical atrophy and cortical thinning occur during untreated infection but may be arrested by cART. These findings emphasize the importance of early cART.
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Antirretrovirales/uso terapéutico , Encéfalo/efectos de los fármacos , Encéfalo/diagnóstico por imagen , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/diagnóstico por imagen , Infecciones por VIH/tratamiento farmacológico , Adulto , Biomarcadores/sangre , Biomarcadores/líquido cefalorraquídeo , Encéfalo/virología , Corteza Cerebral/virología , Estudios Transversales , Quimioterapia Combinada , Femenino , Infecciones por VIH/complicaciones , Humanos , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , NeuroimagenRESUMEN
OBJECTIVE: Advanced endovascular aneurysm repair (EVAR) with fenestrated and branched stent grafts is increasingly being used to repair complex aortic aneurysms; however, these devices can rotate unpredictably during deployment, leading to device misalignment. The objectives of this study were to quantify the short-term clinical outcomes in patients with intraoperative stent graft rotation and to identify quantitative anatomic markers of the arterial geometry that can predict stent graft rotation preoperatively. METHODS: A prospective study evaluating all patients undergoing advanced EVAR was conducted at two university-affiliated hospitals between November 2015 and December 2016. Stent graft rotation (defined as ≥10 degrees) was measured on intraoperative fluoroscopic video of the deployment sequence. Standard preoperative computed tomography angiography imaging was used to calculate the geometric properties of the arterial anatomy. Any in-hospital and 30-day complications were prospectively documented, and a composite outcome of any end-organ ischemia or death was used as the primary end point. RESULTS: Thirty-nine patients undergoing advanced EVAR were enrolled in the study with a mean age of 75 years (interquartile range [IQR], 71-80 years) and a mean aneurysm diameter of 64 mm (IQR, 59-65 mm). The incidence of stent graft rotation was 37% (n = 14), with a mean rotation of 25 degrees (IQR, 21-28 degrees). A nominal logistic regression model identified iliac artery torsion, volume of iliac artery calcification, and stent graft length as the primary predictive factors. The total net torsion and the total volume of calcific plaque were higher in patients with stent graft rotation, 8.9 ± 0.8 mm-1 vs 4.1 ± 0.5 mm-1 (P < .0001) and 1054 ± 144 mm3 vs 525 ± 83 mm3 (P < .01), respectively. The length of the implanted stent grafts was also higher in patients with intraoperative rotation, 172 ± 9 mm vs 156 ± 8 mm (P < .01). The composite outcome of any end-organ ischemia or death was also substantially higher in patients with stent graft rotation (36% vs 0%; P = .004). In addition, patients with stent graft rotation had significantly higher combined rates of type Ib and type III endoleaks (43% vs 8%; P = .03). CONCLUSIONS: Patients with intraoperative stent graft rotation have a significantly higher rate of severe postoperative complications, and this is strongly associated with higher levels of iliac artery torsion, calcification, and stent graft length. These findings suggest that preoperative quantitative analysis of iliac artery torsion and calcification may improve risk stratification of patients before advanced EVAR.
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Aneurisma de la Aorta/cirugía , Implantación de Prótesis Vascular/efectos adversos , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/efectos adversos , Procedimientos Endovasculares/instrumentación , Migración de Cuerpo Extraño/etiología , Stents , Anciano , Anciano de 80 o más Años , Aneurisma de la Aorta/diagnóstico por imagen , Aneurisma de la Aorta/mortalidad , Aortografía/métodos , Implantación de Prótesis Vascular/mortalidad , Angiografía por Tomografía Computarizada , Endofuga/etiología , Procedimientos Endovasculares/mortalidad , Femenino , Migración de Cuerpo Extraño/diagnóstico por imagen , Migración de Cuerpo Extraño/mortalidad , Hospitales Universitarios , Humanos , Arteria Ilíaca/diagnóstico por imagen , Modelos Logísticos , Masculino , Análisis Multivariante , Ontario , Estudios Prospectivos , Diseño de Prótesis , Radiografía Intervencional , Factores de Riesgo , Rotación , Factores de Tiempo , Resultado del Tratamiento , Calcificación Vascular/complicaciones , Calcificación Vascular/diagnóstico por imagenRESUMEN
Importance: Despite the introduction of combination antiretroviral therapy (cART), HIV-associated neurocognitive disorders continue to be a problem for treated HIV-positive individuals. The cause of this impairment remains unclear. Objective: To determine if detectable brain changes occur during a 2-year period in HIV-positive individuals who were aviremic and treated with cART. Design, Setting, and Participants: In this longitudinal case-control study, participants underwent neuroimaging and neuropsychological assessment approximately 2 years apart. Data were collected from October 26, 2011, to March 1, 2016. Data from 92 HIV-positive individuals were acquired at Washington University in St Louis from ongoing studies conducted in the infectious disease clinic and AIDS Clinical Trial Unit. A total of 55 HIV-negative control participants were recruited from the St Louis community and a research participant registry. A total of 48 HIV-positive individuals who were aviremic and treated with cART and 31 demographically similar HIV-negative controls met the study requirements and were included in the analyses. Main Outcomes and Measures: Brain volumes were extracted with tensor-based and voxel-based morphometry and cortical modeling. Raw scores from neuropsychological tests quantified cognitive performance. Multivariable mixed-effects models assessed the effect of HIV serostatus on brain volumes and cognitive performance, and determined if HIV serostatus affected how these measures changed over time. With HIV-positive participants, linear regression models tested whether brain volumes and cognitive performance were associated with measures of infection severity and duration of infection. Results: The 2 groups were demographically similar (HIV-positive group: 23 women and 25 men; mean [SD] age, 47.7 [13.2] years; mean [SD] educational level, 13.3 [3.4] years; and HIV-negative group, 16 women and 15 men; mean [SD] age, 51.2 [12.9] years; mean [SD] educational level, 14.5 [2.1] years). The HIV-positive participants had poorer neuropsychological test scores compared with controls on the Trail Making Test Part A (5.9 seconds; 95% CI, 1.5-10.3; P = .01), Trail Making Test Part B (27.3 seconds; 95% CI, 15.0-39.6; P < .001), Digit Symbol Substitution Task (-12.5 marks; 95% CI, -18.9 to -6.0; P < .001), Letter-Number Sequencing (-2.5 marks; 95% CI, -3.7 to -1.3; P < .001), Letter Fluency (-6.6 words; 95% CI, -11.5 to -1.6; P = .01), and Hopkins Verbal Learning Test-Revised immediate recall (-2.4 words; 95% CI, -4.4 to -0.4; P = .05), after adjusting for age, sex, and educational level. Only changes in Trail Making Test Part A significantly differed between the groups. Cortical thickness and subcortical volumes were smaller in HIV-positive individuals compared with controls. However, changes in brain volume over time were similar between the groups. Conclusions and Relevance: These findings are consistent with the idea that cognitive and structural brain changes may occur early after seroconversion, and argue that maintaining aviremia with cART can prevent or minimize progressive brain injury.
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Antirretrovirales/uso terapéutico , Encéfalo/efectos de los fármacos , Trastornos del Conocimiento/tratamiento farmacológico , Infecciones por VIH , Adulto , Anciano , Encéfalo/diagnóstico por imagen , Estudios de Casos y Controles , Trastornos del Conocimiento/virología , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Humanos , Procesamiento de Imagen Asistido por Computador , Estudios Longitudinales , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Our voice provides salient cues about how confident we sound, which promotes inferences about how believable we are. However, the neural mechanisms involved in these social inferences are largely unknown. Employing functional magnetic resonance imaging, we examined the brain networks and individual differences underlying the evaluation of speaker believability from vocal expressions. Participants (n = 26) listened to statements produced in a confident, unconfident, or "prosodically unmarked" (neutral) voice, and judged how believable the speaker was on a 4-point scale. We found frontal-temporal networks were activated for different levels of confidence, with the left superior and inferior frontal gyrus more activated for confident statements, the right superior temporal gyrus for unconfident expressions, and bilateral cerebellum for statements in a neutral voice. Based on listener's believability judgment, we observed increased activation in the right superior parietal lobule (SPL) associated with higher believability, while increased left posterior central gyrus (PoCG) was associated with less believability. A psychophysiological interaction analysis found that the anterior cingulate cortex and bilateral caudate were connected to the right SPL when higher believability judgments were made, while supplementary motor area was connected with the left PoCG when lower believability judgments were made. Personal characteristics, such as interpersonal reactivity and the individual tendency to trust others, modulated the brain activations and the functional connectivity when making believability judgments. In sum, our data pinpoint neural mechanisms that are involved when inferring one's believability from a speaker's voice and establish ways that these mechanisms are modulated by individual characteristics of a listener. Hum Brain Mapp 38:3732-3749, 2017. © 2017 Wiley Periodicals, Inc.
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How the kidney prevents urinary excretion of plasma proteins continues to be debated. Here, using unfixed whole-mount mouse kidneys, we show that fluorescent-tagged proteins and neutral dextrans permeate into the glomerular basement membrane (GBM), in general agreement with Ogston's 1958 equation describing how permeation into gels is related to molecular size. Electron-microscopic analyses of kidneys fixed seconds to hours after injecting gold-tagged albumin, negatively charged gold nanoparticles, and stable oligoclusters of gold nanoparticles show that permeation into the lamina densa of the GBM is size-sensitive. Nanoparticles comparable in size with IgG dimers do not permeate into it. IgG monomer-sized particles permeate to some extent. Albumin-sized particles permeate extensively into the lamina densa. Particles traversing the lamina densa tend to accumulate upstream of the podocyte glycocalyx that spans the slit, but none are observed upstream of the slit diaphragm. At low concentrations, ovalbumin-sized nanoparticles reach the primary filtrate, are captured by proximal tubule cells, and are endocytosed. At higher concentrations, tubular capture is saturated, and they reach the urine. In mouse models of Pierson's or Alport's proteinuric syndromes resulting from defects in GBM structural proteins (laminin ß2 or collagen α3 IV), the GBM is irregularly swollen, the lamina densa is absent, and permeation is increased. Our observations indicate that size-dependent permeation into the lamina densa of the GBM and the podocyte glycocalyx, together with saturable tubular capture, determines which macromolecules reach the urine without the need to invoke direct size selection by the slit diaphragm.
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Membrana Basal Glomerular/metabolismo , Túbulos Renales/metabolismo , Sustancias Macromoleculares/metabolismo , Animales , Femenino , Membrana Basal Glomerular/ultraestructura , Oro , Humanos , Lactante , Recién Nacido , Túbulos Renales/ultraestructura , Túbulos Renales Proximales/metabolismo , Masculino , Nanopartículas del Metal , Ratones , Microscopía Confocal , Permeabilidad , Podocitos/metabolismoRESUMEN
BACKGROUND: Cognitive impairment still occurs in a substantial subset of HIV-infected patients, despite effective viral suppression with highly active antiretroviral therapy (HAART). Structural brain changes may provide clues about the underlying pathophysiology. This study provides a detailed spatial characterization of the pattern and extent of brain volume changes associated with HIV and relates these brain measures to cognitive ability and clinical variables. METHODS: Multiple novel neuroimaging techniques (deformation-based morphometry, voxel-based morphometry, and cortical modeling) were used to assess regional brain volumes in 125 HIV-infected patients and 62 HIV-uninfected individuals. Ninety percent of the HIV-infected patients were on stable HAART with most of them (75%) having plasma viral suppression. Brain volumetrics and cortical thickness estimates were compared between the HIV-infected and uninfected groups, and the relationships between these measures of brain volume and indices of current and past infection severity, central nervous system penetration of HAART, and cognitive performance were assessed. RESULTS: Regionally specific patterns of reduced thalamic and brainstem volumes and reduced cortical thickness in the orbitofrontal cortex, cingulate gyrus, primary motor and sensory cortex, temporal, and frontal lobes were seen in HIV-infected patients compared to HIV-uninfected participants. Observed white matter loss and subcortical atrophy were associated with lower nadir CD4 cell counts, while reduction in cortical thickness was related to worse cognitive performance. CONCLUSIONS: Our findings suggest that distinct mechanisms may underlie cortical and subcortical injury in people with HIV and argues for the potential importance of early initiation of HAART to protect long-term brain health.
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Complejo SIDA Demencia/patología , Antirretrovirales/uso terapéutico , Terapia Antirretroviral Altamente Activa/métodos , Encéfalo/patología , Infecciones por VIH/complicaciones , Infecciones por VIH/tratamiento farmacológico , Complejo SIDA Demencia/diagnóstico por imagen , Adulto , Biometría , Encéfalo/diagnóstico por imagen , Cognición , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroimagen , Pruebas NeuropsicológicasRESUMEN
OBJECTIVE: In situ fenestration of endovascular stent grafts has been used as a method for branch vessel revascularization in urgent and emergent settings. The objective of this manuscript was to review the clinical and experimental evidence related to this technique. METHODS: PubMed, MEDLINE, and Embase databases were searched for papers published until December 2015 describing in situ fenestration of aortic stent grafts. Benchtop, animal, and human studies were included. RESULTS: The literature review identified 118 articles, of which 28 studies were selected for inclusion. These included 16 clinical papers (2 case series and 14 case reports) reporting in situ fenestration of 46 aortic branch vessels in 44 patients. There were 42 retrograde and 4 antegrade instances of in situ fenestration. The most frequent target vessel for in situ fenestration was the left subclavian artery (72%), and the most frequent indication for stent graft implantation was a degenerative aortic aneurysm (43%). Technical success was reported in 44 of 46 attempted fenestrations (96%). The combined rate of perioperative mortality, stroke, and paralysis was 7%. In situ fenestration was predominantly performed with the Talent (Medtronic, Santa Rosa, Calif) stent graft (54%), followed by the Zenith (Cook Medical, Bloomington, Ind) stent graft (37%) and the TAG (W. L. Gore & Associates, Newark, Del) stent graft (9%). In vitro benchtop evaluations of in situ fenestration showed minimal change in fenestration size after 1 year of pulsatile fatigue testing. The use of energy-based fenestration techniques (radiofrequency or laser) has been associated with less fabric fraying than in needle-based techniques. The larger caliber initial fenestration created by these devices also avoids the need for cutting balloons, which have also been linked with increased fabric tears and fraying of the fibers surrounding the fenestration. In addition, the Zenith stent graft was shown in benchtop testing to be the strongest in postfenestration mechanical testing, but it was also the most resistant to balloon dilation. CONCLUSIONS: In the short to moderate term, in situ fenestration appears to be a reasonable and effective method to extend the proximal landing zone for revascularization of the left subclavian artery. However, longer follow-up is needed to fully assess the long-term durability of this procedure. Based on studies of material properties, an energy-based fenestration technique (radiofrequency or laser) is recommended, along with the avoidance of cutting balloons for dilation of the fenestration.
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Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Stents , Animales , Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/diagnóstico por imagen , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Humanos , Diseño de Prótesis , Falla de Prótesis , Factores de Riesgo , Arteria Subclavia/diagnóstico por imagen , Arteria Subclavia/cirugía , Factores de Tiempo , Resultado del TratamientoRESUMEN
Diabetic nephropathy is the major cause of end-stage renal disease worldwide. Although the renin-angiotensin system has been implicated in the pathogenesis of diabetic nephropathy, angiotensin I-converting enzyme inhibitors have a beneficial effect on diabetic nephropathy independently of their effects on blood pressure and plasma angiotensin II levels. This suggests that the kallikrein-kinin system (KKS) is also involved in the disease. To study the role of the KKS in diabetic nephropathy, mice lacking either the bradykinin B1 receptor (B1R) or the bradykinin B2 receptor (B2R) have been commonly used. However, because absence of either receptor causes enhanced expression of the other, it is difficult to determine the precise functions of each receptor. This difficulty has recently been overcome by comparing mice lacking both receptors with mice lacking each receptor. Deletion of both B1R and B2R reduces nitric oxide (NO) production and aggravates renal diabetic phenotypes, relevant to either lack of B1R or B2R, demonstrating that both B1R and B2R exert protective effects on diabetic nephropathy presumably via NO. Here, we review previous epidemiological and experimental studies, and discuss novel insights regarding the therapeutic implications of the importance of the KKS in averting diabetic nephropathy.
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Nefropatías Diabéticas/fisiopatología , Sistema Calicreína-Quinina/fisiología , Alelos , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Animales , Nefropatías Diabéticas/etiología , Nefropatías Diabéticas/patología , Nefropatías Diabéticas/terapia , Humanos , Ratones , Ratones Noqueados , Modelos Biológicos , Óxido Nítrico/fisiología , Estrés Oxidativo , Peptidil-Dipeptidasa A/deficiencia , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/fisiología , Receptor de Bradiquinina B1/deficiencia , Receptor de Bradiquinina B1/genética , Receptor de Bradiquinina B1/fisiología , Receptor de Bradiquinina B2/deficiencia , Receptor de Bradiquinina B2/genética , Receptor de Bradiquinina B2/fisiologíaRESUMEN
Stringent regulation of LH secretion from the pituitary is vital to ovarian function in mammals. Two rodent models of LH hypersecretion are the transgenic LHbeta-C-terminal peptide (LHbetaCTP) and estrogen receptor-alpha (ERalpha)-null (alphaERKO) mice. Both exhibit ovarian phenotypes of chronic anovulation, cystic and hemorrhagic follicles, lack of corpora lutea, interstitial/stromal hyperplasia, and elevated plasma estradiol and testosterone. Because ERbeta is highly expressed in granulosa cells of the ovary, we hypothesized the intraovarian actions of ERbeta may be necessary for full manifestation of phenotypes associated with LH hyperstimulation. To address this question, we generated female mice that possess elevated LH, but lack ERbeta, by breeding the LHbetaCTP and ERbeta-null (betaERKO) mice. A comparison of LHbetaCTP, alphaERKO, and betaERKO(LHCTP) females has allowed us to elucidate the contribution of each ER form to the pathologies and endocrinopathies that occur during chronic LH stimulation of the ovary. alphaERKO ovaries respond to elevated LH by exhibiting an amplified steroidogenic pathway characteristic of the follicular stage of the ovarian cycle, whereas wild-type(LHCTP) and betaERKO(LHCTP) females exhibit a steroidogenic profile more characteristic of the luteal stage. In addition, the hemorrhagic and cystic follicles of the LHbetaCTP and alphaERKO ovaries require the intraovarian actions of ERbeta for manifestation, because they were lacking in the betaERKO(LHCTP) ovary. In turn, ectopic expression of the Leydig cell-specific enzyme, Hsd17b3, and male-like testosterone synthesis in the alphaERKO ovary are unique to this genotype and are therefore the culmination of elevated LH and the loss of functional ERalpha within the ovary.