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1.
Artigo em Inglês | MEDLINE | ID: mdl-38836184

RESUMO

Dual-source photon-counting CT combines the high temporal resolution and high pitch of dual-source CT with the material quantification capabilities of photon-counting CT. It, however, results in cross-scatter that increases in severity with increased patient size and collimation. This cross-scatter must be corrected to ensure the removal of scatter artifacts and improve quantitative accuracy. To evaluate residual cross-scatter of a first-generation dual-source photon-counting CT and the effect of phantom size, collimation, and radiation dose, a phantom was scanned in single- and dual-source modes with and without its extension ring at three collimations and three radiation doses. Virtual monoenergetic images (VMI) at 50 keV, VMI 150 keV, and iodine density maps were reconstructed to determine variation between acquisition parameters in single- and dual-source modes. Additionally, differences relative to single-source acquisitions and to single-source and small collimation acquisitions were calculated to reflect residual cross-scatter with and without matched collimation. At VMI 50 keV, inserts exhibited accuracy and similar variation between single- and dual-source modes, averaging 5.4 ± 2.6 and 6.2 ± 2.5 HU, respectively, across phantom size, collimation, and radiation dose. Differences relative to single-source measured 5.1 ± 8.5 and 0.4 ± 4.2 HU while differences relative to single-source and small collimation acquisitions were 6.4 ± 10.8 HU and -0.5 ± 3.9 HU for VMI 50 and 150 keV, respectively. This minimal residual cross-scatter increases confidence in the quantitative accuracy of spectral results necessary for clinical applications of dual-source photon-counting CT with motion, such as cardiac imaging.

2.
J Appl Clin Med Phys ; : e14383, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38801204

RESUMO

OBJECTIVE: To assess the impact of scatter radiation on quantitative performance of first and second-generation dual-layer spectral computed tomography (DLCT) systems. METHOD: A phantom with two iodine inserts (1 and 2 mg/mL) configured to intentionally introduce high scattering conditions was scanned with a first- and second-generation DLCT. Collimation widths (maximum of 4 cm for first generation and 8 cm for second generation) and radiation dose levels were varied. To evaluate the performance of both systems, the mean CT numbers of virtual monoenergetic images (MonoEs) at different energies were calculated and compared to expected values. MonoEs at 50  versus 150 keV were plotted to assess material characterization of both DLCTs. Additionally, iodine concentrations were determined, plotted, and compared against expected values. For each experimental scenario, absolute errors were reported. RESULTS: An experimental setup, including a phantom design, was successfully implemented to simulate high scatter radiation imaging conditions. Both CT scanners illustrated high spectral accuracy for small collimation widths (1 and 2 cm). With increased collimation (4 cm), the second-generation DLCT outperformed the earlier DLCT system. Further, the spectral performance of the second-generation DLCT at an 8 cm collimation width was comparable to a 4 cm collimation on the first-generation DLCT. A comparison of the absolute errors between both systems at lower energy MonoEs illustrates that, for the same acquisition parameters, the second-generation DLCT generated results with decreased errors. Similarly, the maximum error in iodine quantification was less with second-generation DLCT (0.45  and 0.33 mg/mL for the first and second-generation DLCT, respectively). CONCLUSION: The implementation of a two-dimensional anti-scatter grid in the second-generation DLCT improves the spectral quantification performance. In the clinical routine, this improvement may enable additional clinical benefits, for example, in lung imaging.

3.
Rev Med Inst Mex Seguro Soc ; 61(Suppl 2): S127-S134, 2023 Sep 18.
Artigo em Espanhol | MEDLINE | ID: mdl-38011537

RESUMO

Background: The Tpe interval (Tp-e) in the surface electrocardiogram represents ventricular repolarization, a key phase in the pathogenesis of severe ventricular arrhythmias. However, there are few studies evaluating changes in this electrocardiographic interval as a risk factor for serious arrhythmias in patients with dilated cardiomyopathy. Objective: To determine whether the Tp-e interval prolongation predicts the presence of life-threatening arrhythmias in patients with dilated cardiomyopathy (DCM) with implantable cardioverter-defibrillator (ICD). Material and methods: Analytical, cross-sectional study in patients with DCM with ICDs. The Tp-e interval was measured in the V2 electrocardiographic lead and correlated with the incidence of life-threatening arrhythmias identified by the ICD. Results: 53 patients were recruited, 10 (18.8%) presented life-threatening arrhythmias. Prolongation of Tp-e interval was related to an increase in the incidence of ventricular tachycardia/fibrillation tachycardia (VT/FT) with a mean of 93 ± 20.5 ms (p = 0.003), using ROC curves to determine the thereshold of 90 ms for increased risk of VT/VF with sensitivity of 70% and specificity of 84%, with an area under the curve of 0.798. Conclusion: The prolongation of the ITp-e interval greater than 90 ms in a population with dilated cardiomyopathy predicts the presence of arrhythmic episodes, such as VT and/or VT/FT.


Introducción: el intervalo Tpe (ITp-e) en el electrocardiograma de superficie representa la repolarización ventricular, fase clave en la patogénesis de arritmias ventriculares graves. Sin embargo, existen pocos estudios que evalúen la alteración de este intervalo electrocardiográfico como factor de riesgo de arritmias graves en pacientes con miocardiopatía dilatada. Objetivo: determinar si la prolongación del ITp-e predice la presencia de arritmias potencialmente mortales en pacientes con miocardiopatía dilatada (MCD) portadores de desfibrilador automático implantable (DAI). Material y métodos: estudio, transversal analítico en pacientes con MCD portadores de DAI. Se midió el ITp-e en la derivación electrocardiográfica V2 y se correlacionó con la incidencia de arritmias potencialmente letales identificadas por el DAI. Resultados: se incluyeron 53 pacientes, 10 (18.8%) presentaron arritmias potencialmente mortales. La prolongación del ITp-e se relacionó con aumento de incidencia de taquicardia ventricular/fibrilación ventricular (TV/FV) con media de 93 ± 20.5 ms (p = 0.003), por lo que se determinó mediante curvas ROC el punto de corte de 90 ms para el aumento de riesgo de TV/FV con sensibilidad de 70% y especificidad de 84%, con área bajo la curva de 0.798. Conclusión: la prolongación del intervalo ITp-e > 90 ms en población con miocardiopatía dilatada predice la presencia de episodios arrítmicos como TV o FV.


Assuntos
Cardiomiopatia Dilatada , Taquicardia Ventricular , Humanos , Cardiomiopatia Dilatada/complicações , Cardiomiopatia Dilatada/diagnóstico , Estudos Transversais , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/complicações , Fibrilação Ventricular/etiologia , Taquicardia Ventricular/etiologia , Taquicardia Ventricular/complicações , Eletrocardiografia/efeitos adversos , Fatores de Risco
4.
Tempo psicanál ; 55(1): 301-329, jan.-jun. 2023.
Artigo em Espanhol | LILACS-Express | LILACS, Index Psicologia - Periódicos | ID: biblio-1450577

RESUMO

Pese a las críticas más férreas y actuales por parte de muchas de las disciplinas psi al psicoanálisis insisto en que Freud no está superado. En este artículo intento una aproximación subversiva a la lectura de Freud focalizándola en sus desarrollos respecto del trabajo y la pulsión. Matizando un recorrido puntual por algunos de sus escritos propiamente psicoanalíticos intento rescatar la importancia del concepto de trabajo en la obra de Freud para poder delimitar la necesidad no sólo de un retorno a Freud sino de una lectura económica más allá de la conocida tópica freudiana. Es decir, el concepto de trabajo y de fuerza se encuentran en muchos de los escritos centrales del pensamiento freudiano y por eso es posible hacer una nueva relación entre Freud y Marx. El recorrido por el pensamiento freudiano retoma postulados referentes al trabajo de sueño y de chiste mediante los mecanismos de condensación y desplazamiento y, ulteriormente, recupera la relación entre fuerza y pulsión para poder matizar una respuesta radical desde el pensamiento freudiano a los embates del sistema capitalista. Para esto a lo largo del escrito abordo la noción de socialización a modo de bisagra que permite hilvanar la noción de trabajo en Freud.


Beyond the strongest and most current criticism from many of the psi disciplines to psychoanalysis, I insist that Freud is not overcome. In this article, I try a subversive approach to Freud's work focusing on his developments regarding work and drive. By clarifying a timely tour of his proper psychoanalytic writings, I tried to rescue the importance of the concept of work in Freud's work in order to delimit the need not only for a return to Freud but for an economic reading beyond the well-known Freudian topic. That is, the concept of work and strength are found in many of the central writings of Freudian thought and that is why it is possible to make a new relationship between Freud and Marx. In this sense, Freudian thought takes up postulates referring to dream and joke, work through the mechanisms of condensation and displacement, and recovers the relationship between force and drive to qualify a radical response from Freudian thought to the onslaught of the capitalist system. For this purpose, across this paper, I try to articulate the notion of socialization as a hinge that allows us to combine with Freud's work concept.


Apesar das críticas mais ferozes e atuais da psicanálise por muitas das disciplinas psi, insisto que Freud não é superado. Neste artigo, tento uma abordagem subversiva da leitura de Freud, concentrando-se em seus desenvolvimentos em relação ao trabalho e à pulsão. Ao qualificar um tour preciso de seus escritos propriamente psicanalíticos, tento resgatar a importância do conceito de trabalho na obra de Freud, a fim de delimitar a necessidade não apenas de um retorno a Freud, mas de uma leitura econômica além do conhecido tema freudiano. Ou seja, o conceito de trabalho e força são encontrados em muitos dos escritos centrais do pensamento freudiano é por isso que é possível estabelecer uma relação entre Freud e Marx. A jornada pelo pensamento freudiano retoma postulados referentes ao trabalho dos sonhos e chiste através dos mecanismos de condensação e deslocamento e, posteriormente, recupera a relação entre força e pulsão, a fim de qualificar uma resposta radical do pensamento freudiano aos embates do sistema capitalista. Para isso, ao longo da redação, trato da noção de socialização como uma dobradiça que nos permite unir a noção de trabalho em Freud.

5.
Biol Pharm Bull ; 46(6): 781-787, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37258142

RESUMO

Anti-inflammatory and analgesic medications (AAMs) are widely used in Mexico and the rest of the world. Their excessive acquisition can lead to waste, representing an unnecessary expense for families and the public health system. The aim of this study was to estimate the economic cost of the waste of unused AAMs collected by the National System for the Collection of Residues of Containers and Medications (SINGREM, the acronym in Spanish) in Mexico City during 2019. Data from SINGREM on discarded AAMs in Mexico City were classified by the type and quantity of drug, pharmaceutical dosage form, origin, dose, and the complete or incomplete condition of the package. The unitary cost for each medication was based on public tenders of the Mexican Social Security Institute (IMSS) for the public sector and the prices in large drug store franchises for the private sector. A decision-making model was constructed to appraise the total cost of discarded AAMs. The economic cost of the 48924 units of discarded AAMs in SINGREM containers in Mexico City during 2019 was approx. USD$143500, of which over USD$127000 corresponded to the private health sector. The current findings evidence an enormous accumulation of unneeded or expired AAMs in Mexico City. According to the present data, the cost of such waste is substantial. The estimated cost was 8-fold higher for discarded medications originating from the private versus the public healthcare sector. It is important to implement measures to prevent this waste and increase awareness of the consequences of inadequate drug disposal.


Assuntos
Analgésicos , Atenção à Saúde , Humanos , México , Analgésicos/uso terapêutico , Anti-Inflamatórios
6.
Opt Express ; 30(9): 15211-15226, 2022 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-35473248

RESUMO

Compton backscattering imaging (CBI) is a technique that uses ionizing radiation to detect the presence of low atomic number materials on a given target. Unlike transmission x-ray imaging, the source and sensor are located on the same side, such that the photons of interest are scattered back after the radiation impinges on the body. Rather than scanning the target pixel by pixel with a pencil-beam, this paper proposes the use of cone-beam coded illumination to create the compressive x-ray Compton backscattering imager (CXBI). The concept was developed and tested using Montecarlo simulations through the Geant4 application for tomography emissions (GATE), with conditions close to the ones encountered in experiments, and posteriorly, a test-bed implementation was mounted in the laboratory. The CXBI was evaluated under several conditions and with different materials as target. Reconstructions were run using denoising-prior-based inverse problem algorithms. Finally, a preliminary dose analysis was done to evaluate the viability of CXBI for human scanning.


Assuntos
Algoritmos , Fótons , Humanos , Tomografia Computadorizada por Raios X/métodos , Raios X
7.
J Comput Assist Tomogr ; 46(2): 224-230, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35081601

RESUMO

OBJECTIVE: This study aimed to evaluate distal triceps tendon tear patterns using a systematic classification based on the tendon's layered structure. METHODS: We retrospectively identified Magnetic resonance imaging (MRI) examinations with triceps tendon tears that underwent reconstructive surgery. Magnetic resonance images were reviewed independently by 2 musculoskeletal radiologists to determine tendon layer involvement and ancillary findings, including tear size, involvement of triceps lateral expansion, and presence of olecranon bursal fluid. Surgical reports were scrutinized for level of anatomic detail and correlation with imaging findings. RESULTS: We identified 69 triceps tendon tears in 68 subjects (61 men, 7 women; mean age, 45 ± 12 years) who underwent surgical reconstruction. On MRI, the superficial layer was always involved with either a partial or full-thickness tear. The most common tear pattern was a combination of superficial layer full-thickness tear with deep layer partial tear (25 of 69 [36%]). Mean tear length was 24 ± 12 mm. We found no cases of isolated deep layer tears. Involvement of triceps lateral expansion and presence of bursal fluid correlated positively with tear severity of superficial and deep layers (P < 0.001). Detailed surgical correlation was limited, with only 9 of 69 (13%) of surgical reports containing information specifically addressing individual tendon layers. CONCLUSIONS: Triceps tendon tears show tear patterns following its layered structure and can be assessed by MRI. Radiologists and surgeons are encouraged to describe tear patterns considering both superficial and deep tendon layers.


Assuntos
Articulação do Cotovelo , Lesões do Manguito Rotador , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Ruptura/diagnóstico por imagem , Tendões/diagnóstico por imagem
8.
Ter. psicol ; 39(3): 353-374, dic. 2021. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1390470

RESUMO

Resumen: Antecedentes: Aunque en el mundo anglosajón la Terapia Afirmativa tiene un amplio recorrido con un respaldo empírico contundente, en Iberoamérica su desarrollo es reciente. Objetivo: Analizar la Evidencia Basada en la Práctica de una red de servicios de psicología afirmativa para personas LGTBIQA+ en Ecuador. Método: Estudio naturalístico en el que se analiza la Evidencia Basada en la Práctica generada usando el Clinical Outcomes in Routine Evaluation - Outcome Measure como herramienta de evaluación rutinaria para monitorizar los resultados de 101 consultantes que recibieron Terapia Afirmativa entre 2018 y 2020 en una red de servicios de psicología afirmativa para personas LGTBIQA+. Se evaluó el cambio estadísticamente significativo y el cambio confiable y clínicamente significativo. Resultados: Lxs participantes tenían en promedio 27.14 años. La mediana de sesiones fue seis. Hubo cambios estadísticamentes significativos para quienes completaron el cuestionario al menos dos veces. Se encontró un tamaño del efecto grande para el puntaje total y todas las dimensiones, a excepción de Riesgo. El 68% de los participantes presentaron mejoría. Conclusiones: Los resultados sugieren que la Terapia Afirmativa minimiza el riesgo que trae consigo el estrés de minorías. Se invita a estudiantes, terapeutas y usuarios a aprender, adoptar y acudir a Terapia Afirmativa, respectivamente.


Abstract: Background: Although in the Anglo-Saxon world Affirmative Therapy has a long history with strong empirical support, in Ibero-America its development is recent. Objective: To analyze the Practice-Based Evidence of a network of affirmative psychology services for LGTBIQA+ persons in Ecuador. Methods: This is a naturalistic study analyzing Practice-Based Evidence generated using the Clinical Outcomes in Routine Evaluation - Outcome Measure as a routine evaluation tool to monitor the outcomes of 101 clients who received Affirmative Therapy between 2018 and 2020 in a network of affirmative psychology services for LGTBIQA+ people. Statistically significant change and reliable, clinically meaningful change were assessed. Results: Participants were on average 27.14 years old. The median number of sessions was six. There were statistically significant changes for those who completed the questionnaire at least twice. A large effect size was found for the total score and all dimensions except for Risk. Sixty-eigth percent participants showed improvement. Conclusions: The results suggest that Affirmative Therapy minimizes the risk brought on by minority stress. Students, therapists, and clients are encouraged to learn, adopt, and use Affirmative Therapy, respectively.


Assuntos
Humanos , Masculino , Feminino , Terapias Complementares , Minorias Sexuais e de Gênero , Equador
9.
Molecules ; 26(8)2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33917871

RESUMO

Indazole is an important scaffold in medicinal chemistry. At present, the progress on synthetic methodologies has allowed the preparation of several new indazole derivatives with interesting pharmacological properties. Particularly, the antiprotozoal activity of indazole derivatives have been recently reported. Herein, a series of 22 indazole derivatives was synthesized and studied as antiprotozoals. The 2-phenyl-2H-indazole scaffold was accessed by a one-pot procedure, which includes a combination of ultrasound synthesis under neat conditions as well as Cadogan's cyclization. Moreover, some compounds were derivatized to have an appropriate set to provide structure-activity relationships (SAR) information. Whereas the antiprotozoal activity of six of these compounds against E. histolytica, G. intestinalis, and T. vaginalis had been previously reported, the activity of the additional 16 compounds was evaluated against these same protozoa. The biological assays revealed structural features that favor the antiprotozoal activity against the three protozoans tested, e.g., electron withdrawing groups at the 2-phenyl ring. It is important to mention that the indazole derivatives possess strong antiprotozoal activity and are also characterized by a continuous SAR.


Assuntos
Antiprotozoários/síntese química , Antiprotozoários/farmacologia , Quimioinformática , Indazóis/síntese química , Indazóis/farmacologia , Antiprotozoários/química , Entamoeba histolytica/efeitos dos fármacos , Giardia lamblia/efeitos dos fármacos , Indazóis/química , Concentração Inibidora 50 , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Trichomonas vaginalis/efeitos dos fármacos , Ultrassom
10.
Pharmaceuticals (Basel) ; 14(3)2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33668364

RESUMO

Candidiasis, caused by yeasts of the genus Candida, is the second cause of superficial and mucosal infections and the fourth cause of bloodstream infections. Although some antifungal drugs to treat candidiasis are available, resistant strains to current therapies are emerging. Therefore, the search for new candicidal compounds is certainly a priority. In this regard, a series of indazole and pyrazole derivatives were designed in this work, employing bioisosteric replacement, homologation, and molecular simplification as new anticandidal agents. Compounds were synthesized and evaluated against C. albicans, C. glabrata, and C. tropicalis strains. The series of 3-phenyl-1H-indazole moiety (10a-i) demonstrated to have the best broad anticandidal activity. Particularly, compound 10g, with N,N-diethylcarboxamide substituent, was the most active against C. albicans and both miconazole susceptible and resistant C. glabrata species. Therefore, the 3-phenyl-1H-indazole scaffold represents an opportunity for the development of new anticandidal agents with a new chemotype.

11.
Skeletal Radiol ; 50(1): 97-106, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32638058

RESUMO

OBJECTIVE: To examine the effect of external hip rotation on ischiofemoral (IF) and quadratus femoris (QF) spaces using real-time kinematic MRI, with the hypothesis that hips with IF and QF space narrowing have distinct motion patterns compared with control hips. MATERIALS AND METHODS: This prospective study was IRB-approved and complied with HIPAA guidelines. We recruited women (≥ 18 years) with and without ischiofemoral impingement to undergo kinematic MRI of the hips. A kinematic imaging protocol using T2-HASTE was performed beginning at maximal internal rotation followed by active external hip rotation. The duration of each acquisition was 30 s, providing 8 images/3 s. IF and QF spaces, and femoral metaphyseal and lesser trochanter centroid coordinates were measured on sequential images. Hips were classified as controls or narrowed based on IF and QF space thresholds and compared statistically throughout motion stages. RESULTS: The cohort comprised 12 women (24 hips; 10 control and 14 narrowed hips) aged 58 ± 10 years. External rotation caused IF space reduction of 59% in narrowed hips versus 41% in control hips. QF space decreased 71% in narrowed hips versus 50% in control hips. IF and QF spaces differed significantly between groups only when external rotation exceeded the neutral position (P < 0.02 for both). The lesser trochanter terminated more posteriorly in narrowed hips compared with controls (P = 0.03). CONCLUSIONS: Kinematic MRI during external hip rotation in women with narrowed and control hips reveals dynamic differences in IF and QF spaces and lesser trochanter terminal position.


Assuntos
Impacto Femoroacetabular , Imageamento por Ressonância Magnética , Fenômenos Biomecânicos , Feminino , Fêmur/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Estudos Prospectivos
12.
Skeletal Radiol ; 48(3): 413-419, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30215105

RESUMO

OBJECTIVE: To determine the role of brown adipose tissue (BAT) in cancer activity. MATERIALS AND METHODS: The study group comprised 142 patients (121 female, 21 male; mean age, 49 ± 16 years) who underwent F18-FDG PET/CT (PET/CT) for staging or surveillance of cancer and who were BAT-positive on PET/CT. BAT volume by PET/CT, abdominal (visceral and subcutaneous) fat and paraspinous muscle cross-sectional areas (CSA) were assessed. Groups with and without active cancer on PET/CT were compared using a two-sided paired t test. Linear regression analyses between BAT and body composition parameters were performed. RESULTS: There were 62 patients (54 female, eight male) who had active cancer on PET/CT and 80 patients (67 female, 13 male) without active cancer. Groups were similar in age and BMI (p ≥ 0.4), abdominal fat and muscle CSA, fasting glucose, and outside temperature at time of scan (p ≥ 0.2). Patients who had active cancer on PET/CT had higher BAT volume compared to patients without active cancer (p = 0.009). In patients without active cancer, BAT was positively associated with BMI and abdominal fat depots (r = 0.46 to r = 0.59, p < 0.0001) while there were no such associations in patients with active cancer (p ≥ 0.1). No associations between BAT and age or muscle CSA were found (p ≥ 0.1). CONCLUSIONS: BAT activity is greater in patients with active cancer compared to age-, sex-, and BMI-matched BAT-positive patients without active cancer, suggesting a possible role of BAT in cancer activity.


Assuntos
Tecido Adiposo Marrom/diagnóstico por imagem , Neoplasias/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Tecido Adiposo Marrom/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Composição Corporal , Feminino , Fluordesoxiglucose F18 , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/patologia , Compostos Radiofarmacêuticos , Estudos Retrospectivos
13.
J Endocr Soc ; 2(10): 1147-1157, 2018 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-30283827

RESUMO

OBJECTIVE: Fatty liver disease is increased among individuals with HIV. We sought to explore how aldosterone, a key hormone linked to insulin resistance and inflammation, relates to liver fat in the large population of individuals with HIV and metabolic abnormalities. METHODS: Forty-six individuals with HIV and increased waist circumference and dysglycemia were assessed for liver fat using proton magnetic resonance spectroscopy. Serum aldosterone level was obtained following strictly controlled posture conditions and a standardized sodium diet and was related to liver fat. RESULTS: Among the entire group [median (interquartile range) liver fat: 5% (3%, 12%) and homeostatic model assessment of insulin resistance: 1.74 (1.21, 2.83)], serum aldosterone significantly correlated with liver fat (r = 0.31; P = 0.049). Liver fat level was significantly higher in those with aldosterone above vs below the median [8% (3%, 20%) vs 4% (2%, 10%); P = 0.02]. In the presence of metabolic syndrome, individuals with aldosterone levels above vs below the median had markedly elevated liver fat values [14% (9%, 23%) vs 5% (3%, 12%); P = 0.005] and increased presence of fatty liver disease (FLD; 92% vs 50%; P = 0.02). Controlling for metabolic syndrome, hepatitis C virus, and alcohol use, aldosterone was a significant and independent predictor of liver fat (ß estimate: 0.6038, P = 0.01; overall model r 2 = 0.41, P = 0.0005) and FLD (OR: 1.38, P = 0.02; overall model r 2 = 0.28, P = 0.002). CONCLUSION: These data highlight a robust association between aldosterone and liver fat among individuals with HIV and metabolic dysregulation. Increased aldosterone may be a risk factor for liver fat accumulation among the population with HIV.

14.
J Clin Endocrinol Metab ; 103(11): 4176-4186, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30239757

RESUMO

Context: 3-Hydroxy-3-methyl-glutaryl-coenzyme A reductase inhibitors (statins) are widely prescribed. Statins may have important metabolic effects on insulin sensitivity and liver fat, but limited studies have assessed these effects by using euglycemic hyperinsulinemic clamp, stable isotopes, and 1H magnetic resonance spectroscopy (MRS) for liver fat quantification. Objective: To study the effects of pitavastatin on hepatic fat and insulin sensitivity. Design: Six-month, double-blind, randomized, placebo-controlled trial. Setting: Academic clinical research center in Boston, Massachusetts. Participants: Overweight, insulin-resistant men aged 40 to 65 years who had not received statin therapy for ≥1 year. Interventions: Pitavastatin 4 mg or placebo daily. Outcome: The primary endpoints were changes in insulin sensitivity measured by euglycemic hyperinsulinemic clamp and liver fat measured by 1H MRS. Results: Pitavastatin showed no effect on endogenous glucose production (ΔRa glucose 0.07 ± 0.07 vs 0.04 ± 0.07 mg/kg/min, pitavastatin vs placebo, P = 0.76) or insulin-stimulated glucose uptake during "low dose" (ΔM 0.1 ± 0.1 vs -0.3 ± 0.2 mg/kg/min, P = 0.11) and "high dose" (ΔM -0.5 ± 0.3 vs -0.7 ± 0.4 mg/kg/min, P = 0.70) euglycemic hyperinsulinemic clamps. There was also no effect of pitavastatin on fasting glucose, HbA1c, and 2-hour glucose after 75-g glucose challenge. There was also no change in liver fat fraction (-1 ± 1 vs -0 ± 1%, P = 0.56). Conclusion: Compared with placebo, pitavastatin did not affect hepatic or whole-body insulin sensitivity, and it did not reduce liver fat.


Assuntos
Fígado Gorduroso/prevenção & controle , Inibidores de Hidroximetilglutaril-CoA Redutases/administração & dosagem , Resistência à Insulina , Sobrepeso/metabolismo , Quinolinas/administração & dosagem , Adulto , Glicemia/análise , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Método Duplo-Cego , Fígado Gorduroso/diagnóstico por imagem , Fígado Gorduroso/etiologia , Fígado Gorduroso/patologia , Técnica Clamp de Glucose , Humanos , Insulina/metabolismo , Fígado/diagnóstico por imagem , Fígado/efeitos dos fármacos , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Sobrepeso/sangue , Sobrepeso/complicações , Espectroscopia de Prótons por Ressonância Magnética , Resultado do Tratamento
15.
J Clin Endocrinol Metab ; 103(6): 2376-2384, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29659888

RESUMO

Context: HIV-infected individuals demonstrate increased renin-angiotensin-aldosterone system activation in association with visceral adiposity, insulin resistance, and inflammation. A physiologically based treatment approach targeting mineralocorticoid receptor (MR) blockade may improve metabolic and inflammatory indices in HIV. Objective: To investigate effects of eplerenone on insulin sensitivity, inflammatory indices, and other metabolic parameters in HIV. Design: Six-month, double-blind, randomized, placebo-controlled trial. Setting: Academic clinical research center. Participants: HIV-infected individuals with increased waist circumference and abnormal glucose homeostasis. Intervention: Eplerenone 50 mg or placebo daily. Outcome: The primary end point was change in insulin sensitivity measured by the euglycemic-hyperinsulinemic clamp technique. Secondary end points included change in body composition and inflammatory markers. Results: Forty-six individuals were randomized to eplerenone (n = 25) vs placebo (n = 21). Eplerenone did not improve insulin sensitivity [0.48 (-1.28 to 1.48) vs 0.43 (-1.95 to 2.55) mg/min/µIU/mL insulin; P = 0.71, eplerenone vs placebo] when measured by the gold standard euglycemic-hyperinsulinemic clamp technique. Intramyocellular lipids (P = 0.04), monocyte chemoattractant protein-1 (P = 0.04), and high-density lipoprotein (P = 0.04) improved among those randomized to eplerenone vs placebo. Trends toward decreases in interleukin-6 (P = 0.10) and high-sensitivity C-reactive protein (P = 0.10) were also seen with eplerenone vs placebo. Plasma renin activity and aldosterone levels increased in the eplerenone vs placebo-treated group, demonstrating expected physiology. MR antagonism with eplerenone was well tolerated among the HIV population, with no considerable changes in blood pressure or potassium. Conclusion: MR blockade may improve selected metabolic and inflammatory indices in HIV-infected individuals. Further studies are necessary to understand the clinical potential of MR antagonism in HIV.


Assuntos
Adiposidade/efeitos dos fármacos , Eplerenona/uso terapêutico , Infecções por HIV/metabolismo , Inflamação/tratamento farmacológico , Resistência à Insulina/fisiologia , Antagonistas de Receptores de Mineralocorticoides/uso terapêutico , Adulto , Idoso , Pressão Sanguínea/efeitos dos fármacos , Método Duplo-Cego , Eplerenona/administração & dosagem , Feminino , Técnica Clamp de Glucose , Infecções por HIV/complicações , Humanos , Inflamação/complicações , Inflamação/metabolismo , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Antagonistas de Receptores de Mineralocorticoides/administração & dosagem , Sistema Renina-Angiotensina/efeitos dos fármacos , Resultado do Tratamento
16.
Acta Radiol ; 59(10): 1203-1209, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29444586

RESUMO

Background Recent studies suggest that pericardial adipose tissue (PAT) is associated with whole body adiposity and insulin resistance. Moreover, the incidence of cardiovascular disease (CVD) differs between men and women. Although CVD is more prevalent in men, women suffering from CVD have a higher mortality compared to men. Differences in PAT may account for some of the observed sex differences in manifestations of CVD. Purpose To assess pericardial adipose tissue (PAT) as a biomarker for cardiometabolic risk and to assess potential sex differences. Material and Methods We studied 303 individuals (151 women, 152 men; mean age = 57 ± 17 years) across the weight spectrum. PAT and abdominal adipose tissue were quantified using clinical computed tomography (CT) scans obtained as part of a positron emission tomography (PET)/CT. Cardiometabolic risk factors were assessed from medical records. Linear regression and receiver operating characteristic (ROC) curve analyses were performed to evaluate associations between PAT and cardiometabolic risk. Results PAT was higher in overweight and obese individuals compared to lean individuals and higher in men compared to women. PAT was positively associated with body mass index, abdominal fat ( P < 0.0001), fasting glucose, and serum lipids ( P < 0.05) with stronger associations in women than in men. PAT was accurate in detecting the prevalence of the metabolic syndrome with 74% sensitivity and 76% specificity (AUC = 0.80). Conclusion PAT is associated with measures of cardiometabolic risk and these associations are stronger in women compared to men. PAT could serve as a biomarker for opportunistic screening for cardiometabolic risk in patients undergoing chest CT.


Assuntos
Tecido Adiposo/diagnóstico por imagem , Síndrome Metabólica/epidemiologia , Pericárdio/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores , Doenças Cardiovasculares/diagnóstico por imagem , Feminino , Fluordesoxiglucose F18 , Humanos , Resistência à Insulina , Masculino , Pessoa de Meia-Idade , Obesidade , Sobrepeso , Prevalência , Compostos Radiofarmacêuticos , Estudos Retrospectivos , Fatores de Risco , Sensibilidade e Especificidade , Fatores Sexuais
17.
Skeletal Radiol ; 47(8): 1127-1135, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29426957

RESUMO

OBJECTIVE: To evaluate the significance of biceps tendon (BT) displacement and peri-bicipital hematoma on MRI in subjects with pectoralis major (PM) tears. We hypothesized that these features might be associated with tear severity at surgery. MATERIALS AND METHODS: We retrospectively identified MRI cases with PM injury and reviewed clinical, imaging, and surgical records. MR images were reviewed independently by two musculoskeletal radiologists to determine anterior displacement of BT (BT-disp, in mm) and the presence of triangular-shaped peri-bicipital hematoma. Data were compared with an age- and sex-matched control group and correlated with surgical reports grouped by tear severity. RESULTS: We identified 46 subjects with PM injury (43 men, 3 women; mean age 34 ± 9 years), 26 of whom underwent surgical reconstruction, and 20 matched controls (P > 0.2). BT-disp was significantly higher in PM injury vs controls (P = 0.003), and in tendon vs myotendinous (MT) junction PM tears (P < 0.0001); however, MT junction tears vs controls were similar (P = 0.98). Higher BT-disp and presence of peri-bicipital hematoma correlated significantly with surgical reports describing full-thickness complete tears. BT-disp > 4.5 mm had 86% sensitivity and 75% specificity to detect the most severe tears on surgical reports, whereas the presence of peri-bicipital hematoma was the strongest predictor among both parameters. CONCLUSION: Anterior BT displacement and peri-bicipital hematoma are helpful indicators of full-thickness complete tears at the humeral insertion.


Assuntos
Músculos Peitorais/lesões , Ruptura/diagnóstico por imagem , Adulto , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/etiologia , Estudos de Casos e Controles , Feminino , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doenças Musculares/diagnóstico por imagem , Doenças Musculares/etiologia , Músculos Peitorais/diagnóstico por imagem , Estudos Retrospectivos , Traumatismos dos Tendões/diagnóstico por imagem , Adulto Jovem
18.
Skeletal Radiol ; 47(5): 747-750, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29285554

RESUMO

Triggering of the toes is rare, with isolated cases reported in the literature involving predominantly the flexor hallucis longus (FHL) tendon, a condition known as "hallux saltans" (HS). We report the dynamic sonographic findings of a 42-year-old female with a 2-month history of ankle pain and triggering of right hallux, consistent with HS. Sonography demonstrated tenosynovitis and focal thickening of FHL at the level of hindfoot, with a fibrous band adjacent to the tendon. Dynamic ultrasound showed triggering and snapping of FHL tendon during hallux flexion and extension, respectively. We present comprehensive documentation of this rare entity, including sonographic still images and cine clips, as well as correlation with arthroscopic surgical findings.


Assuntos
Hallux/diagnóstico por imagem , Encarceramento do Tendão/diagnóstico por imagem , Dedos do Pé , Adulto , Artroscopia , Feminino , Hallux/cirurgia , Humanos , Encarceramento do Tendão/cirurgia , Ultrassonografia
19.
Skeletal Radiol ; 46(10): 1367-1378, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28660403

RESUMO

OBJECTIVE: Hemispherical spondylosclerosis (HS) is a rare degenerative entity characterized by dome-shaped sclerosis of a single vertebral body that may pose a diagnostic dilemma. The goal of this study was to describe the MR imaging features of HS. MATERIALS AND METHODS: We identified spine radiographs and CT examinations of subjects with HS who also had MR imaging for correlation. Two musculoskeletal radiologists independently assessed sclerosis characteristics, presence of endplate erosions, marrow signal intensity, and disk degeneration (Pfirrmann scale). RESULTS: We identified 11 subjects (six males, five females, mean 48 ± 10 years) with radiographic/CT findings of HS. The most commonly affected vertebral body was L4 (6/11; 55%). On MR imaging, variable signal intensity was noted, being most commonly low on T1 (8/11, 73%) and high on fat-suppressed T2-weighted (8/11, 73%) images. In two subjects, diffuse post-contrast enhancement was seen in the lesion. Moderate disk degeneration and endplate bone erosions adjacent to sclerosis were present in all subjects. Erosions of the opposite endplate were present in two subjects (2/11, 18%). CT data from nine subjects showed the mean attenuation value of HS was 472 ± 96 HU. CONCLUSIONS: HS appearance on MR imaging is variable and may not correlate with the degree of sclerosis seen on radiographs or CT. Disk degenerative changes and asymmetric endplate erosions are consistent markers of HS.


Assuntos
Imageamento por Ressonância Magnética/métodos , Espondilose/diagnóstico por imagem , Espondilose/patologia , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X
20.
Magn Reson Imaging Clin N Am ; 25(1): 45-61, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27888851

RESUMO

Acute and chronic ankle inversion injuries are a common source of pain and a diagnostic challenge. Several studies have shown a variety of injury patterns after inversion injury both in acute and chronic settings. Although traditional assessment with clinical examination and radiographs is generally accepted for inversion injuries, MR imaging is a useful tool to detect occult injuries and in patients with chronic symptoms. This article examines a range of MR imaging findings that may be present in patients with lateral ankle pain following an acute or chronic inversion injury.


Assuntos
Traumatismos do Tornozelo/diagnóstico por imagem , Instabilidade Articular/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Traumatismos dos Tendões/diagnóstico por imagem , Traumatismos do Tornozelo/fisiopatologia , Articulação do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/fisiopatologia , Humanos , Instabilidade Articular/fisiopatologia , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/fisiopatologia , Traumatismos dos Tendões/fisiopatologia
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