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1.
Retina ; 43(4): 670-678, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36512802

RESUMEN

PURPOSE: To describe bacillary layer detachment and related abnormalities of the foveal bouquet in rhegmatogenous retinal detachment and assess their impact on photoreceptor recovery and full-thickness macular hole formation, using optical coherence tomography. METHODS: Prospective cohort of 93 consecutive patients with fovea-off rhegmatogenous retinal detachment presenting to St. Michael's Hospital from January 2020 to April 2022, with gradable preoperative foveal optical coherence tomography. RESULTS: 23.7% (22/93) of patients had evidence of bacillary layer detachment and associated abnormalities. The mean fovea-off duration was 6.4 days (±5.6 SD). 86.4% (19/22) had foveal bacillary layer detachment, 15.8% (3/19) of which had cleavage planes extending from the outer nuclear layer into the myoid zone, and 14% (3/22) had an inner lamellar hole with a residual bridge of photoreceptor remnants (all of which progressed to full-thickness macular hole). Among patients with gradable optical coherence tomography at 3 months post-operatively, 80% (12/15) had ellipsoid zone discontinuity, which persisted in 41% (5/12) at 1 year. CONCLUSION: Bacillary layer detachment was described for the first time in the setting of rhegmatogenous retinal detachment. This is hypothesized to occur from horizontal traction secondary to hydration/lateral expansion of the outer retina in the presence of the Müller cell cone scaffold. Bacillary layer detachment may render the fovea susceptible to further injury, possibly representing a pathophysiological basis for full-thickness macular hole formation in rhegmatogenous retinal detachment.


Asunto(s)
Bacillus , Desprendimiento de Retina , Perforaciones de la Retina , Humanos , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/cirugía , Perforaciones de la Retina/diagnóstico , Perforaciones de la Retina/cirugía , Estudios Prospectivos , Retina , Tomografía de Coherencia Óptica/métodos
2.
JAMA ; 330(22): 2171-2181, 2023 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-37950897

RESUMEN

IMPORTANCE: Left ventricular assist devices (LVADs) enhance quality and duration of life in advanced heart failure. The burden of nonsurgical bleeding events is a leading morbidity. Aspirin as an antiplatelet agent is mandated along with vitamin K antagonists (VKAs) with continuous-flow LVADs without conclusive evidence of efficacy and safety. OBJECTIVE: To determine whether excluding aspirin as part of the antithrombotic regimen with a fully magnetically levitated LVAD is safe and decreases bleeding. DESIGN, SETTING, and PARTICIPANTS: This international, randomized, double-blind, placebo-controlled study of aspirin (100 mg/d) vs placebo with VKA therapy in patients with advanced heart failure with an LVAD was conducted across 51 centers with expertise in treating patients with advanced heart failure across 9 countries. The randomized population included 628 patients with advanced heart failure implanted with a fully magnetically levitated LVAD (314 in the placebo group and 314 in the aspirin group), of whom 296 patients in the placebo group and 293 in the aspirin group were in the primary analysis population, which informed the primary end point analysis. The study enrolled patients from July 2020 to September 2022; median follow-up was 14 months. Intervention: Patients were randomized in a 1:1 ratio to receive aspirin (100 mg/d) or placebo in addition to an antithrombotic regimen. MAIN OUTCOMES AND MEASURES: The composite primary end point, assessed for noninferiority (-10% margin) of placebo, was survival free of a major nonsurgical (>14 days after implant) hemocompatibility-related adverse events (including stroke, pump thrombosis, major bleeding, or arterial peripheral thromboembolism) at 12 months. The principal secondary end point was nonsurgical bleeding events. RESULTS: Of the 589 analyzed patients, 77% were men; one-third were Black and 61% were White. More patients were alive and free of hemocompatibility events at 12 months in the placebo group (74%) vs those taking aspirin (68%). Noninferiority of placebo was demonstrated (absolute between-group difference, 6.0% improvement in event-free survival with placebo [lower 1-sided 97.5% CI, -1.6%]; P < .001). Aspirin avoidance was associated with reduced nonsurgical bleeding events (relative risk, 0.66 [95% confidence limit, 0.51-0.85]; P = .002) with no increase in stroke or other thromboembolic events, a finding consistent among diverse subgroups of patient characteristics. CONCLUSIONS AND RELEVANCE: In patients with advanced heart failure treated with a fully magnetically levitated LVAD, avoidance of aspirin as part of an antithrombotic regimen, which includes VKA, is not inferior to a regimen containing aspirin, does not increase thromboembolism risk, and is associated with a reduction in bleeding events. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04069156.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Accidente Cerebrovascular , Tromboembolia , Masculino , Humanos , Femenino , Aspirina/efectos adversos , Corazón Auxiliar/efectos adversos , Fibrinolíticos/efectos adversos , Método Doble Ciego , Insuficiencia Cardíaca/fisiopatología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/prevención & control , Accidente Cerebrovascular/tratamiento farmacológico , Inhibidores de Agregación Plaquetaria/efectos adversos , Hemorragia/etiología , Tromboembolia/etiología , Tromboembolia/prevención & control
3.
Bioconjug Chem ; 33(5): 892-906, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35420782

RESUMEN

Aberrant insulin signaling has been considered one of the risk factors for the development of Alzheimer's disease (AD) and has drawn considerable attention from the research community to further study its role in AD pathophysiology. Herein, we describe the development of an insulin-based novel positron emission tomography (PET) probe, [68Ga]Ga-NOTA-insulin, to noninvasively study the role of insulin in AD. The developed PET probe [68Ga]Ga-NOTA-insulin showed a significantly higher uptake (0.396 ± 0.055 SUV) in the AD mouse brain compared to the normal (0.140 ± 0.027 SUV) mouse brain at 5 min post injection and also showed a similar trend at 10, 15, and 20 min post injection. In addition, [68Ga]Ga-NOTA-insulin was found to have a differential uptake in various brain regions at 30 min post injection. Among the brain regions, the cortex, thalamus, brain stem, and cerebellum showed a significantly higher standard uptake value (SUV) of [68Ga]Ga-NOTA-insulin in AD mice as compared to normal mice. The inhibition of the insulin receptor (IR) with an insulin receptor antagonist peptide (S961) in normal mice showed a similar brain uptake profile of [68Ga]Ga-NOTA-insulin as it was observed in the AD case, suggesting nonfunctional IR in AD and the presence of an alternative insulin uptake route in the absence of a functional IR. The Gjedde-Patlak graphical analysis was also performed to predict the input rate of [68Ga]Ga-NOTA-insulin into the brain using MicroPET imaging data and supported the in vivo results. The [68Ga]Ga-NOTA-insulin PET probe was successfully synthesized and evaluated in a mouse model of AD in comparison with [18F]AV1451 and [11C]PIB to noninvasively study the role of insulin in AD pathophysiology.


Asunto(s)
Enfermedad de Alzheimer , Radioisótopos de Galio , Enfermedad de Alzheimer/diagnóstico por imagen , Animales , Compuestos Heterocíclicos con 1 Anillo , Insulina , Ratones , Tomografía de Emisión de Positrones/métodos , Receptor de Insulina
4.
Catheter Cardiovasc Interv ; 100(2): 266-273, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35612519

RESUMEN

BACKGROUND: Left ventricular assist devices (LVAD) outflow graft obstruction is an uncommon complication but carries significant morbidity and mortality. Here we provide a case series of patients with LVAD intrinsic outflow graft obstruction who are deemed to be a high surgical risk for pump exchange and, therefore, underwent percutaneous intervention with the concomitant use of neuroprotective device-Sentinel cerebral protection system (CPS) (Boston Scientific) to prevent embolic stroke. METHODS: We retrospectively analyzed patients who underwent LVAD placement in our institution and developed LVAD outflow graft obstruction. The diagnosis of LVAD outflow graft obstruction was confirmed by utilizing various cardiac imaging modalities such as echocardiography and/or computed tomography angiography. All patients were treated with percutaneous intervention and a catheter-based CPS. RESULTS: From a total of 501 LVAD implants in our institute, 6 (1.2%) patients with LVAD outflow graft obstruction who underwent percutaneous treatment were included; 4 patients with HeartMate-III LVAD, 1 patient with HeartMate-II LVAD, and 1 patient with HeartWare (HVAD). The median age of patients was 56.5 years at the time of LVAD implantation. The median time from the LVAD implantation to the episode of LVAD outflow obstruction was 1343 days. Utilization of Sentinel CPS resulted in the capture and removal of thrombus/debris in all patients. CONCLUSIONS: Percutaneous intervention of LVAD outflow graft obstruction is less invasive than surgical pump exchange and an acceptable alternative in properly selected patients. In our experience, utilization of a catheter-based CPS can help in reducing the incidence of periprocedural embolic events.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Trombosis , Obstrucción del Flujo Ventricular Externo , Ecocardiografía/efectos adversos , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/etiología , Insuficiencia Cardíaca/terapia , Corazón Auxiliar/efectos adversos , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Trombosis/etiología , Resultado del Tratamiento , Obstrucción del Flujo Ventricular Externo/etiología
5.
J Card Surg ; 37(7): 1907-1914, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35385586

RESUMEN

BACKGROUND: The European CE Mark approval study and the MOMENTUM 3 trial demonstrated safety and a reduction in hemocompatibility-related adverse events with the use of HeartMate 3 (HM3) device. This single-center study investigated the real-world experience in HM3 patients since FDA approval. METHODS: This retrospective, observational study included patients implanted with the HM3 LVAD as a primary implant between October 2017 and March 2020. Patients were divided into trial group and postapproval group. The primary endpoint was survival at 6 months. Secondary endpoints were adverse events including pump thrombosis (requiring pump exchange), stroke, renal failure, acute limb ischemia, re-exploratory for bleeding, gastrointestinal bleeding, right ventricular failure, and driveline infection. RESULTS: A total of 189 patients were implanted with HM3 device during the study period. 174 patients met the inclusion criteria: 82 patients in the trial group and 92 patients in the postapproval group. The postapproval group had younger patients, higher preoperative mean international normalized ratio, and greater numbers of patients with bridge to transplant (BTT) indications, IINTERMACS profile 1, and use of mechanical assist devices (other than IABP) than the trial group. Other characteristics between the two groups were comparable. Overall survival at 6 months in the postapproval group was 93.3% versus 93.8% (p = .88). The postapproval group demonstrated a statistically significant lower incidence of re-explorative surgery for bleeding (10.9% vs. 46.3, p = .01) than the trial group. CONCLUSION: In this single-center study, the real-world 6-month survival in the postapproval group was comparable to the trial results. Further studies are needed to monitor long-term outcomes.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Accidente Cerebrovascular , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar/efectos adversos , Humanos , Estudios Retrospectivos , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Resultado del Tratamiento
6.
Gastroenterology ; 159(4): 1487-1503.e17, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32574624

RESUMEN

BACKGROUND & AIMS: Endoplasmic reticulum to nucleus signaling 1 (ERN1, also called IRE1A) is a sensor of the unfolded protein response that is activated in the livers of patients with nonalcoholic steatohepatitis (NASH). Hepatocytes release ceramide-enriched inflammatory extracellular vesicles (EVs) after activation of IRE1A. We studied the effects of inhibiting IRE1A on release of inflammatory EVs in mice with diet-induced steatohepatitis. METHODS: C57BL/6J mice and mice with hepatocyte-specific disruption of Ire1a (IRE1αΔhep) were fed a diet high in fat, fructose, and cholesterol to induce development of steatohepatitis or a standard chow diet (controls). Some mice were given intraperitoneal injections of the IRE1A inhibitor 4µ8C. Mouse liver and primary hepatocytes were transduced with adenovirus or adeno-associated virus that expressed IRE1A. Livers were collected from mice and analyzed by quantitative polymerase chain reaction and chromatin immunoprecipitation assays; plasma samples were analyzed by enzyme-linked immunosorbent assay. EVs were derived from hepatocytes and injected intravenously into mice. Plasma EVs were characterized by nanoparticle-tracking analysis, electron microscopy, immunoblots, and nanoscale flow cytometry; we used a membrane-tagged reporter mouse to detect hepatocyte-derived EVs. Plasma and liver tissues from patients with NASH and without NASH (controls) were analyzed for EV concentration and by RNAscope and gene expression analyses. RESULTS: Disruption of Ire1a in hepatocytes or inhibition of IRE1A reduced the release of EVs and liver injury, inflammation, and accumulation of macrophages in mice on the diet high in fat, fructose, and cholesterol. Activation of IRE1A, in the livers of mice, stimulated release of hepatocyte-derived EVs, and also from cultured primary hepatocytes. Mice given intravenous injections of IRE1A-stimulated, hepatocyte-derived EVs accumulated monocyte-derived macrophages in the liver. IRE1A-stimulated EVs were enriched in ceramides. Chromatin immunoprecipitation showed that IRE1A activated X-box binding protein 1 (XBP1) to increase transcription of serine palmitoyltransferase genes, which encode the rate-limiting enzyme for ceramide biosynthesis. Administration of a pharmacologic inhibitor of serine palmitoyltransferase to mice reduced the release of EVs. Levels of XBP1 and serine palmitoyltransferase were increased in liver tissues, and numbers of EVs were increased in plasma, from patients with NASH compared with control samples and correlated with the histologic features of inflammation. CONCLUSIONS: In mouse hepatocytes, activated IRE1A promotes transcription of serine palmitoyltransferase genes via XBP1, resulting in ceramide biosynthesis and release of EVs. The EVs recruit monocyte-derived macrophages to the liver, resulting in inflammation and injury in mice with diet-induced steatohepatitis. Levels of XBP1, serine palmitoyltransferase, and EVs are all increased in liver tissues from patients with NASH. Strategies to block this pathway might be developed to reduce liver inflammation in patients with NASH.


Asunto(s)
Endorribonucleasas/fisiología , Vesículas Extracelulares/patología , Hepatocitos/patología , Enfermedad del Hígado Graso no Alcohólico/etiología , Enfermedad del Hígado Graso no Alcohólico/patología , Proteínas Serina-Treonina Quinasas/fisiología , Animales , Ceramidas/metabolismo , Modelos Animales de Enfermedad , Masculino , Ratones , Ratones Endogámicos C57BL , Enfermedad del Hígado Graso no Alcohólico/metabolismo
7.
Inorg Chem ; 59(17): 12025-12038, 2020 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-32820888

RESUMEN

Four tris-bidentate catecholamide (CAM) ligands were synthesized, characterized, and evaluated as ligands for radiolabeling of gallium-68 for positron emission tomography (PET). Three of those ligands, 2,2-Glu-CAM, 3,3-Glu-CAM, and TREN-bisGlyGlu-CAM, incorporate ligand caps that contain a pendant carboxylic group for further conjugation to targeting moieties. The acyclic ligands all exhibited high (>80%) radiolabeling yields after short reaction times (<10 min) at room temperature, a distinct advantage over macrocyclic analogues that display slower kinetics. The stabilities of the four GaIII complexes are comparable to or higher than those of other acyclic ligands used for gallium-68 PET imaging, such as desferrioxamine, with pGa values ranging from 21 to >24, although the functionalizable ligands are less stable than the parent GaIII-TREN-CAM. In vivo imaging studies and ex vivo pharmacokinetic and biodistribution studies indicate that the parent [68Ga]Ga-TREN-CAM is stable in vivo but is rapidly cleared in <15 min, probably via a renal pathway. The rapid and mild radiolabeling conditions, high radiolabeling yields, and high stability in human serum (>95%) render TREN-bisGlyGlu-CAM a promising candidate for gallium-68 chelation.


Asunto(s)
Catecoles/química , Radioisótopos de Galio/química , Tomografía de Emisión de Positrones/métodos , Animales , Estabilidad de Medicamentos , Humanos , Marcaje Isotópico , Cinética , Ligandos , Ratones , Temperatura
8.
Am J Physiol Renal Physiol ; 316(2): F263-F273, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30520657

RESUMEN

Zinc (Zn2+) is the second most abundant trace element, but is considered a micronutrient, as it is a cofactor for many enzymes and transcription factors. Whereas Zn2+ deficiency can cause cognitive immune or metabolic dysfunction and infertility, excess Zn2+ is nephrotoxic. As for other ions and solutes, Zn2+ is moved into and out of cells by specific membrane transporters: ZnT, Zip, and NRAMP/DMT proteins. ZIP10 is reported to be localized at the apical membrane of renal proximal tubules in rats, where it is believed to play a role in Zn2+ import. Renal regulation of Zn2+ is of particular interest in light of growing evidence that Zn2+ may play a role in kidney stone formation. The objective of this study was to show that ZIP10 homologs transport Zn2+, as well as ZIP10, kidney localization across species. We cloned ZIP10 from dog, human, and Drosophila ( CG10006), tested clones for Zn2+ uptake in Xenopus oocytes and localized the protein in renal structures. CG10006, rather than foi (fear-of-intimacy, CG6817) is the primary ZIP10 homolog found in Drosophila Malpighian tubules. The ZIP10 antibody recognizes recombinant dog, human, and Drosophila ZIP10 proteins. Immunohistochemistry reveals that ZIP10 in higher mammals is found not only in the proximal tubule, but also in the collecting duct system. These ZIP10 proteins show Zn2+ transport. Together, these studies reveal ZIP10 kidney localization, a role in renal Zn2+ transport, and indicates that CG10006 is a Drosophila homolog of ZIP10.


Asunto(s)
Proteínas de Transporte de Catión/metabolismo , Clonación Molecular , Proteínas de Drosophila/metabolismo , Túbulos Renales Colectores/metabolismo , Túbulos Renales Proximales/metabolismo , Túbulos de Malpighi/metabolismo , Zinc/metabolismo , Animales , Transporte Biológico , Proteínas de Transporte de Catión/genética , Perros , Proteínas de Drosophila/genética , Humanos , Especificidad de la Especie , Xenopus laevis
9.
Am J Physiol Endocrinol Metab ; 316(2): E251-E259, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30512988

RESUMEN

The ability of heart and skeletal muscle (SM) to switch between fat and carbohydrate oxidation is of high interest in the study of metabolic diseases and exercise physiology. Positron emission tomography (PET) imaging with the glucose analog 2-[18F]fluoro-2-deoxy-glucose (18F-FDG) provides a noninvasive means to quantitate glucose metabolic rates. However, evaluation of fatty acid oxidation (FAO) rates by PET has been limited by the lack of a suitable FAO probe. We have developed a metabolically trapped oleate analog, ( Z)-18-[18F]fluoro-4-thia-octadec-9-enoate (18F-FTO), and investigated the feasibility of using 18F-FTO and 18F-FDG to measure FAO and glucose uptake, respectively, in heart and SM of rats in vivo. To enhance the metabolic rates in SM, the vastus lateralis (VL) muscle was electrically stimulated in fasted rats for 30 min before and 30 min following radiotracer injection. The responses of radiotracer uptake patterns to pharmacological inhibition of FAO were assessed by pretreatment of the rats with the carnitine palmitoyl-transferase-1 (CPT-1) inhibitor sodium 2-[5-(4-chlorophenyl)-pentyl]oxirane-2-carboxylate (POCA). Small-animal PET images and biodistribution data with 18F-FTO and 18F-FDG demonstrated profound metabolic switching for energy provision in the myocardium from exogenous fatty acids to glucose in control and CPT-1-inhibited rats, respectively. Uptake of both radiotracers was low in unstimulated SM. In stimulated VL muscle, 18F-FTO and 18F-FDG uptakes were increased 4.4- and 28-fold, respectively, and CPT-1 inhibition only affected 18F-FTO uptake (66% decrease). 18F-FTO is a FAO-dependent PET probe that may allow assessment of energy substrate metabolic switching in conjunction with 18F-FDG and other metabolic probes.


Asunto(s)
Ácidos Grasos/metabolismo , Glucosa/metabolismo , Corazón/diagnóstico por imagen , Miocardio/metabolismo , Músculo Cuádriceps/diagnóstico por imagen , Músculo Cuádriceps/metabolismo , Animales , Carnitina O-Palmitoiltransferasa/antagonistas & inhibidores , Compuestos Epoxi/farmacología , Fluorodesoxiglucosa F18 , Ácido Láctico/metabolismo , Contracción Muscular , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Ácidos Oléicos , Oxidación-Reducción , Tomografía Computarizada por Tomografía de Emisión de Positrones , Músculo Cuádriceps/efectos de los fármacos , Radiofármacos , Ratas , Sulfuros , Distribución Tisular , Triglicéridos/metabolismo
10.
J Card Surg ; 34(11): 1393-1395, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31441552

RESUMEN

We present the first case of ischemic stroke secondary to massive air embolus during implantation of a left ventricular assist device (LVAD). The patient experienced a suction event at the time of aortic cannula removal. Despite the use of all standard deairing techniques and flooding the operative field with continuous-flow carbon dioxide, a significant amount of air was delivered into the ascending aorta through the LVAD pump.


Asunto(s)
Embolia Aérea/etiología , Corazón Auxiliar/efectos adversos , Accidente Cerebrovascular/etiología , Humanos
11.
J Card Surg ; 34(12): 1629-1631, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31609485

RESUMEN

Right ventricular failure continues to be the Achilles heel in the management of heart failure patients. Traditionally, either high doses of inotropes and inhaled nitric oxide or jerry-rigged temporary mechanical devices have been used to support failing right ventricles. No durable implantable right ventricular assist device has been developed to address this long-standing concern. Because of this vacuum of innovation, surgeons have started using the third-generation LVADs to support the right ventricle. The HeartMate 3 (Abbott) LVAD is a safe and effective therapy for the management of biventricular failure.


Asunto(s)
Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Diseño de Equipo , Trasplante de Corazón , Humanos , Masculino , Persona de Mediana Edad
12.
J Card Surg ; 34(11): 1383-1386, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31421654

RESUMEN

Children with heart failure have few mechanical circulatory support options and have a high incidence of embolic events. The favorable hemocompatibility and smaller profile of HeartMate 3 may provide more long-term options for the pediatric population.


Asunto(s)
Insuficiencia Cardíaca/terapia , Corazón Auxiliar , Niño , Humanos
13.
Bioorg Med Chem ; 26(1): 225-231, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-29198608

RESUMEN

Noninvasive imaging of iodide uptake via the sodium/iodide symporter (NIS) has received great interest for evaluation of thyroid cancer and reporter imaging of NIS-expressing viral therapies. In this study, we investigate 18F-labeled hexafluorophosphate (HFP or PF6-) as a high-affinity iodide analog for NIS imaging. 18F-HFP was synthesized by radiofluorination of phosphorus pentafluoride·N-methylpyrrolidine complex and evaluated in human NIS (hNIS)-expressing C6 glioma cells and a C6 glioma xenograft mouse model. 18F-HFP was obtained in radiochemical yield of 10 ±â€¯5%, radiochemical purity of >96% and specific radioactivity of 604 ±â€¯18 MBq/µmol. Specific uptake of 18F-HFP and high affinity of 19F-HFP were observed in hNIS+ C6-glioma cells. PET imaging showed robust uptake of 18F-HFP in NIS-expressing tissues (thyroid, stomach, and hNIS+ C6 glioma xenografts), and the uptake of 18F-HFP was blocked by NaClO4 pretreatment. Specific accumulation in hNIS-expressing xenograft (hNIS+) was observed relative to isogenic control tumor (hNIS-). Clearance of 18F-HFP was predominantly through renal excretion. The biodistribution showed consistent results with PET imaging. Minimal bone uptake was observed over 2 h period post-injection, indicating excellent in vivo stability of 18F-HFP. Although improvement in specific radioactivity is desirable, the results indicate that 18F-HFP is a promising candidate radiotracer for further evaluation for NIS imaging.


Asunto(s)
Glioma/diagnóstico por imagen , Imagen Molecular , Tomografía de Emisión de Positrones , Radiofármacos/química , Simportadores/análisis , Animales , Relación Dosis-Respuesta a Droga , Femenino , Radioisótopos de Flúor , Glioma/metabolismo , Humanos , Ratones , Ratones Desnudos , Estructura Molecular , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/metabolismo , Radiofármacos/síntesis química , Radiofármacos/farmacocinética , Relación Estructura-Actividad , Simportadores/metabolismo
14.
Radiology ; 279(2): 513-22, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26583911

RESUMEN

PURPOSE: To determine if adventitial transplantation of human adipose tissue-derived mesenchymal stem cells (MSCs) to the outflow vein of B6.Cg-Foxn1(nu)/J mice with arteriovenous fistula (AVF) at the time of creation would reduce monocyte chemoattractant protein-1 (Mcp-1) gene expression and venous neointimal hyperplasia. The second aim was to track transplanted zirconium 89 ((89)Zr)-labeled MSCs serially with positron emission tomography (PET) for 21 days. MATERIALS AND METHODS: All animal experiments were performed according to protocols approved by the institutional animal care and use committee. Fifty B6.Cg-Foxn1(nu)/J mice were used to accomplish the study aims. Green fluorescent protein was used to stably label 2.5 × 10(5) MSCs, which were injected into the adventitia of the outflow vein at the time of AVF creation in the MSC group. Eleven mice died after AVF placement. Animals were sacrificed on day 7 after AVF placement for real-time polymerase chain reaction (n = 6 for MSC and control groups) and histomorphometric (n = 6 for MSC and control groups) analyses and on day 21 for histomorphometric analysis only (n = 6 for MSC and control groups). In a separate group of experiments (n = 3), animals with transplanted (89)Zr-labeled MSCs were serially imaged with PET for 3 weeks. Multiple comparisons were performed with two-way analysis of variance, followed by the Student t test with post hoc Bonferroni correction. RESULTS: In vessels with transplanted MSCs compared with control vessels, there was a significant decrease in Mcp-1 gene expression (day 7: mean reduction, 62%; P = .029), with a significant increase in the mean lumen vessel area (day 7: mean increase, 176% [P = .013]; day 21: mean increase, 415% [P = .011]). Moreover, this was accompanied by a significant decrease in Ki-67 index (proliferation on day 7: mean reduction, 81% [P = .0003]; proliferation on day 21: mean reduction, 60%, [P = .016]). Prolonged retention of MSCs at the adventitia was evidenced by serial PET images of (89)Zr-labeled cells. CONCLUSION: Adventitial transplantation of MSCs decreases Mcp-1 gene expression, accompanied by a reduction in venous neointimal hyperplasia.


Asunto(s)
Derivación Arteriovenosa Quirúrgica/efectos adversos , Trasplante de Células Madre Mesenquimatosas , Neointima/patología , Tejido Adiposo/citología , Animales , Humanos , Hiperplasia/patología , Hiperplasia/prevención & control , Etiquetado Corte-Fin in Situ , Ratones , Tomografía de Emisión de Positrones , Radiofármacos , Reacción en Cadena en Tiempo Real de la Polimerasa
15.
J Vasc Surg Cases Innov Tech ; 10(2): 101370, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38313380

RESUMEN

Left ventricular assist devices are known for the treatment of heart failure. We present a patient who underwent emergent decommissioning of his left ventricular assist device after experiencing life-threatening hemorrhage. In this case, the patient's outflow graft was avulsed from his left subclavian artery. We used a covered stent to first exclude the outflow graft and an Amplatzer II plug (Abbott Cardiovascular) to then occlude the inflow cannula. Accessing the inflow cannula of the left ventricular assist device was challenging. In hindsight, we could have accessed and occluded the outflow graft via the left subclavian artery before deploying the covered stent.

16.
Cureus ; 16(2): e55298, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38562262

RESUMEN

We present an interesting case of a patient who was discharged from the hospital on daptomycin and ertapenem in the setting of osteomyelitis. The patient did not have any respiratory symptoms during that hospital stay. A few weeks after discharge, the patient came back to the hospital with complaints of fever and shortness of breath. Chest X-ray showed pulmonary infiltrates. Initially, the patient was treated for acute respiratory distress syndrome (ARDS) vs pneumonia, but she did not improve. When labs showed significant eosinophilia, daptomycin-induced eosinophilic pneumonia became the working diagnosis, and the patient improved significantly when daptomycin was discontinued and steroids were started.

17.
Br J Ophthalmol ; 2024 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-38290803

RESUMEN

BACKGROUND: The purpose of the study is to compare visual acuity, complications and outer retinal integrity following subretinal fluid (SRF) drainage from the peripheral retinal breaks (PRBs) versus posterior retinotomy (PR) versus perfluorocarbon liquid (PFCL) for macula-off rhegmatogenous retinal detachments (RRDs) at 2 years post-surgery. METHODS: Retrospective analysis of 300 consecutive patients with primary RRD undergoing 23-gauge pars plana vitrectomy with SRF drainage through (1) PRB (n=100), (2) PR (n=100) or (3) with PFCL (n=100). Primary outcomes were visual acuity (best-corrected visual acuity (BCVA)) and complications (cystoid macular oedema (CMO) and epiretinal membrane (ERM)). Secondary outcomes were discontinuity of the external limiting membrane (ELM), ellipsoid zone (EZ) and interdigitation zone (IDZ) at 2 years post-surgery. RESULTS: Mean (±SD) logMAR BCVA at 24 months was better in the PRB compared with PR and PFCL, with PFCL having the worst BCVA (PRB 0.5±0.6; PR 0.7±0.5; PFCL 0.9±0.7, p=0.001). CMO was higher with PFCL (PRB 29.7%; PR 30.2%; PFCL 45.9%, p=0.0015) and ERM formation was higher in PR (PRB 62.6%; PR 93.0%; PFCL 68.9%, p=0.002). There were no differences in ELM or EZ discontinuity. However, IDZ discontinuity was higher in PFCL (PRB 34%; PR 27%; PFCL 46%, p=0.002) at 2 years. CONCLUSIONS: Visual acuity was worse and discontinuity of the IDZ and CMO was greater in eyes with PFCL-assisted drainage compared with PRB or PR. Drainage technique may impact long-term visual acuity and photoreceptor integrity.

18.
Ophthalmol Retina ; 8(7): 624-632, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38242437

RESUMEN

PURPOSE: To evaluate the association of baseline morphologic stage of rhegmatogenous retinal detachment (RRD) using OCT with postoperative anatomic and visual acuity (VA) outcomes. DESIGN: Retrospective cohort study. SUBJECTS: Consecutive primary fovea-involving RRDs referred from January 2012 to September 2022. METHODS: Patients with primary RRD and no prior macular pathology with gradable baseline OCT were assessed. Best-corrected VA (BCVA) was assessed at presentation and at 3, 6, and 12 months postoperatively. OCT scans were graded for parafoveal morphologic stage of RRD and foveal photoreceptor integrity. MAIN OUTCOME MEASURES: Association of morphologic stage of RRD with 12-month BCVA. RESULTS: Three hundred fifty-one patients were included. Sixty-eight percent (238/351) were male, the mean (standard deviation) age was 61.2 (± 12.8) years, and 59% (206/351) were phakic. Thirteen percent (47/351) presented in stages 1 and 2, 15% (54/351) in stage 3a, 36% (126/351) in stage 3b, 24% (83/351) in stage 4, and 12% (41/351) in stage 5. Increasing stage was associated with worse foveal photoreceptor integrity, reduced baseline BCVA and longer duration of central vision loss (P < 0.001). Mean (standard deviation) 12-month BCVA by stage was 0.77 (± 0.64) for stages 1 and 2, 1.00 (± 0.53) for stage 3a, 1.36 (± 0.55) for stage 3b, 1.33 (± 0.66) for stage 4 and 1.55 (± 0.47) for stage 5. Increasing stage was associated with reduced postoperative BCVA (P < 0.001) at all time points after adjusting for covariates. A subgroup analysis of acute detachments with retinal pigment epithelium-photoreceptor dysregulation demonstrated no difference in postoperative BCVA between stages 1, 2, and 3a. However, 12-month BCVA was significantly better in stages 1, 2, and 3a vs. stage 3b (P = 0.002) and stage 3a vs. 3b (P = 0.008). CONCLUSIONS: This study validates the clinical relevance of a recently proposed OCT-based staging system for outer retinal morphologic changes over time in RRD. Postoperative BCVA was significantly reduced in patients with worse presenting stage at all time points. In acute RRDs, 12-month BCVA was significantly better in stages 1, 2, and 3a vs. stage 3b, which suggests early stages may have better retinal recovery compared with stage 3b or worse. Stage 3b may represent a critical point where substantial structural changes occur, leading to worse outcomes in acute RRDs. Patients presenting with fovea-involving RRDs in stages 1, 2, or 3a may benefit from more urgent intervention. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.


Asunto(s)
Desprendimiento de Retina , Tomografía de Coherencia Óptica , Agudeza Visual , Vitrectomía , Humanos , Desprendimiento de Retina/cirugía , Desprendimiento de Retina/diagnóstico , Desprendimiento de Retina/fisiopatología , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Tomografía de Coherencia Óptica/métodos , Vitrectomía/métodos , Periodo Posoperatorio , Estudios de Seguimiento , Anciano , Fóvea Central/patología , Curvatura de la Esclerótica/métodos
19.
J Vis Exp ; (200)2023 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-37955388

RESUMEN

Stem cell and chimeric antigen receptor (CAR) T-cell therapies are emerging as promising therapeutics for organ regeneration and as immunotherapy for various cancers. Despite significant progress having been made in these areas, there is still more to be learned to better understand the pharmacokinetics and pharmacodynamics of the administered therapeutic cells in the living system. For noninvasive, in vivo tracking of cells with positron emission tomography (PET), a novel [89Zr]Zr-p-isothiocyanatobenzyl-desferrioxamine ([89Zr]Zr-DBN)-mediated cell radiolabeling method has been developed utilizing 89Zr (t1/2 78.4 h). The present protocol describes a [89Zr]Zr-DBN-mediated, ready-to-use, radiolabeling synthon for direct radiolabeling of variety of cells, including mesenchymal stem cells, lineage-guided cardiopoietic stem cells, liver regenerating hepatocytes, white blood cells, melanoma cells, and dendritic cells. The developed methodology enables noninvasive PET imaging of cell trafficking for up to 7 days post-administration without affecting the nature or the function of the radiolabeled cells. Additionally, this protocol describes a stepwise method for the radiosynthesis of [89Zr]Zr-DBN, biocompatible formulation of [89Zr]Zr-DBN, preparation of cells for radiolabeling, and finally the radiolabeling of cells with [89Zr]Zr-DBN, including all the intricate details needed for the successful radiolabeling of cells.


Asunto(s)
Neoplasias , Radioisótopos , Humanos , Radioisótopos/uso terapéutico , Tomografía de Emisión de Positrones/métodos , Neoplasias/tratamiento farmacológico , Inmunoterapia , Inmunoterapia Adoptiva , Circonio , Línea Celular Tumoral
20.
Retin Cases Brief Rep ; 17(3): 247-250, 2023 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-34137737

RESUMEN

PURPOSE: To present a novel technique, minimal gas vitrectomy with scleral buckle, as a means of potentially minimizing retinal displacement compared with standard vitrectomy or vitrectomy/scleral buckle for select cases. METHODS: A patient with right macula-off retinal detachment and retinal breaks at 7 o'clock and 10 o'clock underwent a 23-gauge pars plana vitrectomy, localization, and cryopexy of the breaks along with an inferior temporal segmental scleral buckle. No air-fluid exchange was performed. Suturing of sclerotomies, anterior chamber paracentesis of 0.3 mL, and intravitreal injection of 0.6 mL pure sulfur hexafluoride were then performed. The patient was advised to perform the steamroller maneuver with initial face-down positioning for 6 hours. RESULTS: The patient achieved retinal reattachment, and postoperative wide-field fundus autofluorescence imaging demonstrated high-integrity retinal attachment with no retinal displacement. CONCLUSION: The minimal gas vitrectomy with scleral buckle technique has the potential to minimize retinal displacement in cases with inferior break(s) by using a small volume expansile gas tamponade and localized scleral buckle compared with standard vitrectomy or vitrectomy/scleral buckle with a full gas fill.


Asunto(s)
Desprendimiento de Retina , Humanos , Desprendimiento de Retina/cirugía , Vitrectomía/métodos , Resultado del Tratamiento , Agudeza Visual , Curvatura de la Esclerótica/métodos , Estudios Retrospectivos
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