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1.
Artículo en Inglés | MEDLINE | ID: mdl-38283875

RESUMEN

People living with HIV experience psychosocial needs that often are not addressed. We designed an innovative low-resource model of phone-based psychosocial counseling (P-PSC). We describe cohort characteristics, acceptability, feasibility and utilization of P-PSC at health facilities supported by Baylor Foundation Malawi. Staff were virtually oriented at 120 sites concurrently. From facility-based phones, people with new HIV diagnosis, high viral load, treatment interruption or mental health concerns were referred without identifiable personal information to 13 psychosocial counselors via a WhatsApp group. Routine program data were retrospectively analyzed using univariate approaches and regressions with interrupted time series analyses. Clients utilizing P-PSC were 63% female, 25% youth (10-24 y) and 9% children (<10 y). They were referred from all 120 supported health facilities. Main referral reasons included new HIV diagnosis (32%), ART adherence support (32%) and treatment interruption (21%). Counseling was completed for 99% of referrals. Counseling sessions per month per psychosocial counselor increased from 77 before P-PSC to 216 in month 1 (95% CI = 82, 350, p = 0.003). Total encounters increased significantly to 31,642 in year 1 from ~6,000 during the 12 prior months, an over fivefold increase. P-PSC implementation at 120 remote facilities was acceptable and feasible with immediate, increased utilization despite few psychosocial counselors in Malawi.

2.
Small ; 17(1): e2004823, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33300303

RESUMEN

Engineering electrode materials for optoelectronic and energy storage applications requires a fundamental understanding of intercalation using spatially-resolved techniques. However, spectroscopic methods can have limited spatial resolution and low intensity since the signal passes through electrolyte. Here, a device geometry is presented in which the electrolyte is laterally separated from the area probed spectroscopically, so that the signal does not pass through the electrolyte. This geometry enables us to visualize ion transport with optical microscopy and monitor charge transfer with Raman and visible reflectance spectroscopies. In addition, vibrational changes are probed in the mid-IR, a region previously difficult to access due to electrolyte absorption. This geometry will allow many layered electrodes to be probed in situ using time- and spatially-resolved techniques, including photon and electron spectroscopies.

3.
Adv Mater ; 31(27): e1808213, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31069852

RESUMEN

Intercalation in few-layer (2D) materials is a rapidly growing area of research to develop next-generation energy-storage and optoelectronic devices, including batteries, sensors, transistors, and electrically tunable displays. Identifying fundamental differences between intercalation in bulk and 2D materials will play a key role in developing functional devices. Herein, advances in few-layer intercalation are addressed in the historical context of bulk intercalation. First, synthesis methods and structural properties are discussed, emphasizing electrochemical techniques, the mechanism of intercalation, and the formation of a solid-electrolyte interphase. To address fundamental differences between bulk and 2D materials, scaling relationships describe how intercalation kinetics, structure, and electronic and optical properties depend on material thickness and lateral dimension. Here, diffusion rates, pseudocapacity, limits of staging, and electronic structure are compared for bulk and 2D materials. Next, the optoelectronic properties are summarized, focusing on charge transfer, conductivity, and electronic structure. For energy devices, opportunities also emerge to design van der Waals heterostructures with high capacities and excellent cycling performance. Initial studies of heterostructured electrodes are compared to state-of-the-art battery materials. Finally, challenges and opportunities are presented for 2D materials in energy and optoelectronic applications, along with promising research directions in synthesis and characterization to engineer 2D materials for superior devices.

4.
J Scleroderma Relat Disord ; 3(2): 159-169, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29808171

RESUMEN

PURPOSE: To evaluate the utility of cardiac magnetic resonance (CMR) T1 mapping in early systemic sclerosis (SSc) and its association with skin score. METHODS: Twenty-four consecutive patients with early SSc referred for cardiovascular evaluation and 12 controls without SSc were evaluated. All patients underwent cine, T1 mapping, and late gadolinium enhanced (LGE) CMR imaging. T1 mapping indices were compared between SSc patients and controls (extracellular volume fraction [ECV], gadolinium partition coefficient [λ], pre-contrast T1, and post-contrast T1). The association between T1 mapping parameters and the modified Rodnan skin score (mRSS) was determined. RESULTS: There were no significant differences in cardiac structure/function between SSc patients and controls on cine imaging, and 8/24 (33%) SSc patients had evidence of LGE (i.e., focal myocardial fibrosis). Of the T1 mapping parameters (indices indicative of diffuse myocardial fibrosis), ECV differentiated SSc patients from controls the best, followed by λ, even when the eight SSc patients with LGE were excluded. ECV had a sensitivity and specificity of 75% and 75% for diffuse myocardial fibrosis (optimal abnormal cut-off value of >27% [area under ROC curve=0.85]). In the 16 patients without evidence of LGE, each of the 4 CMR T1 mapping parameters (ECV, λ, Pre-T1 and Post-T1) correlated with mRSS (R=0.51-0.65, P=0.007-0.043), indicating a correlation between SSc cardiac and skin fibrosis. CONCLUSIONS: The four T1 mapping indices are significantly correlated with mRSS in patients with early SSc. Quantification of diffuse myocardial fibrosis using ECV should be considered as a marker for cardiac involvement in SSc clinical studies.

5.
Crit Pathw Cardiol ; 13(4): 135-40, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25396289

RESUMEN

Patients with presumed ST-elevation myocardial infarction (STEMI) have no clear culprit artery in approximately 10-15% of cases. We examined the value of cardiac magnetic resonance (CMR) for diagnosis in patients with "no culprit" STEMI. Data from a comprehensive prospective registry of STEMI patients were reviewed from March 2003 to December 2009. "No culprit" patients were followed for diagnosis and clinical outcome. CMR was performed at the discretion of the attending cardiologist. Of 2728 consecutive presumed STEMI patients, 412 (15%) had no clear culprit artery. Of these, 202 (49%) had abnormal cardiac biomarkers with a definitive diagnosis in 157 (78%). Diagnoses in this group included myocardial infarction without a culprit lesion (24%), myopericarditis (22%), and stress cardiomyopathy (21%). In 210 (51%) patients with normal biomarkers, only 84 (40%) received a definitive diagnosis. Diagnoses in this group included myopericarditis (27%), noncardiac causes (21%), and cardiomyopathy (14%). CMR was performed in 123 (30%) "no culprit" patients. Patients who had CMR were more likely to have a definitive diagnosis than those who did not (95/123 [77%] vs. 144/289 [50%]; P=0.01). In particular, "no culprit" patients with abnormal biomarkers were more likely to have a definitive diagnosis with CMR. CMR led to a diagnosis different from the presumptive clinical diagnosis in 53% of all cases. CMR is a valuable diagnostic tool to improve diagnostic accuracy in patients with "no culprit" STEMI.


Asunto(s)
Electrocardiografía , Imagen por Resonancia Cinemagnética/métodos , Infarto del Miocardio/diagnóstico , Imagen de Perfusión Miocárdica/métodos , Anciano , Biomarcadores , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros
6.
Ann Vasc Surg ; 28(4): 808-15, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24200532

RESUMEN

BACKGROUND: A major factor in the selection of patients for endovascular aneurysm repair (EVAR) is the character of the aortic neck, and studies suggest that many patients are treated outside of the instructions for use (IFU) criteria. By analyzing aortic neck morphology, we hope to identify factors that may influence decision making about the use of fenestrated endografts as an alternative to extending the neck limitations of traditional endografts. METHODS: A retrospective analysis was completed on 111 patients who underwent computed tomography angiography (CTA) scans between May 1, 2009 and January 3, 2011 for the evaluation of abdominal aortic aneurysm (AAA). Individual characteristics of neck and aneurysm morphology were analyzed to establish whether certain factors determined suitability for EVAR with traditional nonfenestrated endografts. In considering augmented neck lengths (ANL), anatomic measurements of distance from the start of aortic dilatation to the lowest renal artery (LRA) and highest renal artery (HRA) were analyzed. Measurements were analyzed using Stata software (version 11.2; StataCorp, College Station, TX). RESULTS: There were 86 men and 25 women in the patient population, with an average age of 72.9 years. In 46 patients, the proximal neck length was <15 mm, with 26 patients having neck lengths <10 mm. There was a negative relationship between AAA maximum diameter and proximal neck length (rs = -0.2237; P = 0.018), indicating that as aneurysm size increases, proximal neck length decreases. There was a significant correlation between proximal neck length and proximal neck diameter (rs = -0.2585; P = 0.006) and between proximal neck length and angle (rs = -0.2355; P = 0.013), and between proximal neck diameter and right iliac maximum diameter (rs = 0.2329; P = 0.014). Using fenestration to place an endograft above the LRA would create an ANL of >15 mm in 20 of 40 patients with aortic necks deemed too short to be eligible for EVAR using conventional infrarenal graft positioning. Extending the graft above the HRA would create an ANL of >15 mm in 36 of 40 patients. DISCUSSION: In this study, 41% of patients presented with neck lengths outside that of the traditional IFU for most aortic endografts. While there was wide variation from patient to patient, there was a general correlation between increasing AAA size and aneurysms that have shorter, wider, and more angulated proximal necks. Fenestration of even 1 renal artery could substantially increase the ANL. Additional study is warranted to determine if an increase in ANL in patients with otherwise short necks will positively impact long-term EVAR outcomes.


Asunto(s)
Aorta Abdominal/cirugía , Aneurisma de la Aorta Abdominal/cirugía , Implantación de Prótesis Vascular/instrumentación , Prótesis Vascular , Procedimientos Endovasculares/instrumentación , Arteria Renal/cirugía , Anciano , Anciano de 80 o más Años , Aorta Abdominal/diagnóstico por imagen , Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Aortografía/métodos , Implantación de Prótesis Vascular/efectos adversos , Procedimientos Endovasculares/efectos adversos , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Selección de Paciente , Valor Predictivo de las Pruebas , Diseño de Prótesis , Arteria Renal/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
7.
Ann Vasc Surg ; 27(4): 497.e15-21, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23548267

RESUMEN

Many disorders can cause aneurysm and/or dissection of the cerebral arteries, including fibromuscular dysplasia (FMD), connective tissue disorders, cerebral vasculitis, infection, and vascular malformations. Arterial fenestration is a rare congenital finding that can also cause aneurysms, and can rarely dissect and bleed. Treatment of aneurysm and dissection with subarachnoid hemorrhage can be very complicated, and requires case-by-case analysis of the risks and benefits of antithrombotic therapy. To the authors' knowledge, no case of double fenestration of the basilar artery has been reported. This report presents a case of concurring vertebral artery dissection and double fenestration of the basilar artery with aneurysm. The fenestration and FMD are considered possible main contributing causes of this presentation. A literature review of cerebrovascular fenestration and FMD is provided and the relationship between the 2 is considered. Lastly, the use of antithrombotic therapy in the setting of subarachnoid hemorrhage, dissection, and stent placement is discussed.


Asunto(s)
Arteria Basilar/anomalías , Aneurisma Intracraneal/congénito , Malformaciones Vasculares/terapia , Procedimientos Quirúrgicos Vasculares/métodos , Disección de la Arteria Vertebral/congénito , Arteria Vertebral/anomalías , Adulto , Arteria Basilar/diagnóstico por imagen , Arteria Basilar/cirugía , Angiografía Cerebral , Diagnóstico Diferencial , Femenino , Humanos , Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Angiografía por Resonancia Magnética , Tomografía Computarizada por Rayos X , Malformaciones Vasculares/cirugía , Arteria Vertebral/diagnóstico por imagen , Arteria Vertebral/cirugía , Disección de la Arteria Vertebral/diagnóstico por imagen , Disección de la Arteria Vertebral/cirugía
9.
Vasc Endovascular Surg ; 46(7): 585-90, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22918938

RESUMEN

Cerebral venous sinus thrombosis (CVST) is a rare cause of stroke, occurring when a blood clot forms in any of the brain venous sinuses. Symptoms include neurological deficits, headache, seizures, and coma. There are many predisposing factors for CVST including prothrombotic conditions, oral contraceptives, pregnancy/puerperium, malignancy, infection, and head injury. Cerebral venous sinus thrombosis has no identifiable underlying etiology in about 12.5% to 33% of the cases. Diagnosis has become easier with newer imaging techniques, such as magnetic resonance venography. The treatment options for CVST include symptomatic treatment, anticoagulation (AC), thrombolysis, and thrombectomy. Controversy exists over the efficacy and safety of AC in patients with CVST with concurrent intracranial hemorrhage (ICH). We present a complex case of CVST with ICH and mastoiditis as well as provide a literature review about CVST.


Asunto(s)
Hemorragias Intracraneales/etiología , Mastoiditis/complicaciones , Trombosis de los Senos Intracraneales/etiología , Anciano , Antibacterianos/uso terapéutico , Anticoagulantes/efectos adversos , Angiografía Cerebral/métodos , Humanos , Hemorragias Intracraneales/diagnóstico , Hemorragias Intracraneales/terapia , Angiografía por Resonancia Magnética , Masculino , Mastoiditis/diagnóstico , Mastoiditis/terapia , Flebografía/métodos , Valor Predictivo de las Pruebas , Trombosis de los Senos Intracraneales/diagnóstico , Trombosis de los Senos Intracraneales/terapia , Trombectomía , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
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