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1.
Nucl Med Biol ; 136-137: 108938, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39032262

RESUMEN

BACKGROUND: Prostate cancer affects 1 in 6 men, and it is the second­leading cause of cancer-related death in American men. Surgery is one of the main treatment modalities for prostate cancer, but it often results in incomplete resection margins or complete resection that leads to nerve damage and undesirable side effects. In the present work, we have developed a new bimodal tracer, NODAGA-sCy7.5 PSMAi (prostate-specific membrane antigen inhibitor), labeled with the true matched theranostic pair 64Cu/67Cu and a near-infrared fluorescent dye. This agent could potentially be used for concomitant PET imaging, optical surgical navigation, and targeted radiopharmaceutical therapy. METHODS: A prostate-specific membrane antigen (PSMA)-targeting urea derivative was conjugated to NODAGA for copper radiolabeling and to the near-infrared fluorophore sulfo-Cy7.5 (sCy7.5). Binding studies were performed in PSMA-positive PC-3 PIP cells, as well as uptake and internalization assays in PC-3 PIP cells and PSMA-negative PC-3 wild type cells. Biodistribution studies of the 64Cu-labeled compound were performed in PC-3 PIP- and PC-3 tumor-bearing mice, and 67Cu biodistributions of the agent were obtained in PC-3 PIP tumor-carrying mice. PET imaging and fluorescence imaging were also performed, using the same molar doses, in the two mouse models. RESULTS: The PSMA conjugate bound with high affinity to PSMA-positive prostate cancer cells, as opposed to cells that were PSMA-negative. Uptake and internalization were rapid and PSMA-mediated in PC-3 PIP cells, while only minimal non-specific uptake was observed in PC-3 cells. Biodistribution studies showed specific uptake in PC-3 PIP tumors, while accumulation in PC-3 tumor-bearing mice was low. Furthermore, tumor uptake of the 67Cu-labeled agent in the PC-3 PIP model was statistically equivalent to that of 64Cu. PET and fluorescence imaging at 0.5 nmol per mouse also demonstrated that PC-3 PIP tumors could be clearly detected, while PC-3 tumors showed no tumor accumulation. CONCLUSIONS: NODAGA-sCy7.5-PSMAi was specific and selective in detecting PSMA-positive, as opposed to PSMA-negative, tumors in mouse models of prostate cancer. This bioconjugate could potentially be used for PET staging with 64Cu, targeted radiopharmaceutical therapy with 67Cu, and/or image-guided surgery with sCy7.5.


Asunto(s)
Antígenos de Superficie , Radioisótopos de Cobre , Glutamato Carboxipeptidasa II , Masculino , Animales , Ratones , Antígenos de Superficie/metabolismo , Glutamato Carboxipeptidasa II/metabolismo , Humanos , Distribución Tisular , Línea Celular Tumoral , Neoplasias de la Próstata/diagnóstico por imagen , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Nanomedicina Teranóstica/métodos , Compuestos Heterocíclicos con 1 Anillo/química , Colorantes Fluorescentes/química , Medicina de Precisión/métodos , Acetatos
2.
Leuk Res Rep ; 19: 100370, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37275466

RESUMEN

We report a case of myeloid/lymphoid neoplasm with ZMYM2::FGFR1 rearrangement (MLNZMYM2::FGFR1) exhibiting a complex disease evolution. This neoplasm initially presented as T-lymphoblastic lymphoma (T-LBL) in lymph node and myeloproliferative neoplasm (MPN) with eosinophilia in bone marrow, then transitioned to systemic mastocytosis (SM) likely accompanied by additional JAK3 and other mutations and finally transformed to acute myeloid leukemia (AML) accompanied by additional/secondary genetic abnormality (gain of chromosome 21, der(13)t(8;13), and RUNX1 mutation). To our knowledge, this is the first case of MLNZMYM2::FGFR1 with a complex trilineage/phenotypic [T-cell (T-LBL), mast cell (SM), and myeloid (MPN and AML)] lineage evolution.

3.
J Diabetes Complications ; 36(8): 108230, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35753926

RESUMEN

AIMS: Low blood 25(OH)D level is associated with increased cardiovascular disease (CVD) risk. Additionally, individuals with prediabetes are at higher risk for CVD than individuals with normoglycemia. We investigated the effects of vitamin D supplementation on CVD outcomes in the vitamin D and type 2 diabetes (D2d) study, a large trial among adults with prediabetes. METHODS: 2423 participants were randomized to 4000 IU/day of vitamin D3 or placebo and followed for median 3.0 years for new-onset diabetes. In pre-specified secondary analyses, we examined the effect of vitamin D supplementation on composite Major Adverse Cardiovascular Events (MACE); expanded MACE (MACE + revascularization); atherosclerotic CVD (ASCVD) risk score; and individual CVD risk factors (blood pressure, lipids, high-sensitivity C-reactive protein). Cox models compared hazard ratios (HR) between the two groups on MACE and expanded MACE. RESULTS: Mean age was 60 years, 45 % were women, 13 % had history of CVD. Twenty-one participants assigned to vitamin D and 12 participants assigned to placebo met the MACE outcome (HR 1.81, 95%CI 0.89 to 3.69). There were 27 expanded MACE outcomes in each group (HR 1.02, 95%CI, 0.59 to 1.76). There were no significant differences between vitamin D and placebo in individual CVD risk factors, but change in ASCVD risk score favored the vitamin D group (-0.45 %, 95%CI -0.75 to -0.15). CONCLUSIONS: In people with prediabetes not selected for vitamin D insufficiency and with intermediate CVD risk, vitamin D supplementation did not decrease MACE but had a small favorable effect on ASCVD risk score. TRIAL REGISTRATION: D2d ClinicalTrials.gov number, NCT01942694, prospectively registered September 16, 2013.


Asunto(s)
Enfermedades Cardiovasculares , Diabetes Mellitus Tipo 2 , Estado Prediabético , Adulto , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/etiología , Enfermedades Cardiovasculares/prevención & control , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Diabetes Mellitus Tipo 2/epidemiología , Suplementos Dietéticos , Método Doble Ciego , Femenino , Factores de Riesgo de Enfermedad Cardiaca , Humanos , Masculino , Persona de Mediana Edad , Estado Prediabético/complicaciones , Estado Prediabético/tratamiento farmacológico , Estado Prediabético/epidemiología , Factores de Riesgo , Vitamina D/uso terapéutico , Vitaminas/uso terapéutico
4.
J Clin Endocrinol Metab ; 106(9): 2767-2778, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-33693713

RESUMEN

CONTEXT: Observational studies suggest that low vitamin D status may be a risk factor for cancer. OBJECTIVE: In a population with prediabetes and overweight/obesity that is at higher risk of cancer than the general population, we sought to determine if vitamin D supplementation lowers the risk of cancer and precancers. METHODS: The Vitamin D and type 2 diabetes (D2d) cancer outcomes study (D2dCA) is an ancillary study to the D2d study, which was conducted at 22 academic medical centers in the United States. Participants had prediabetes and overweight/obesity and were free of cancer for the previous 5 years. Participants were randomized to receive vitamin D3 4000 IU daily or placebo. At scheduled study visits (4 times/year), cancer and precancer events were identified by questionnaires. Clinical data were collected and adjudicated for all reported events. Cox proportional hazard models compared the hazard ratio (HR) of incident cancers and precancers between groups. RESULTS: Over a median follow-up period of 2.9 years, among 2385 participants (mean age 60 years and 25-hydroxyvitamin D 28 ng/mL), there were 89 cases of cancer. The HR of incident cancer for vitamin D vs placebo was 1.07 (95% CI 0.70, 1.62). Of 241 participants with incident precancers, 239 had colorectal adenomatous polyps. The HR for colorectal polyps for vitamin D vs placebo was 0.83 (95% CI 0.64, 1.07). CONCLUSION: In the D2d population of participants with prediabetes and overweight/obesity, not selected for vitamin D insufficiency, vitamin D supplementation did not have a significant effect on risk of incident cancer or colorectal polyps.


Asunto(s)
Neoplasias/prevención & control , Obesidad/complicaciones , Sobrepeso/complicaciones , Estado Prediabético/complicaciones , Vitamina D/administración & dosificación , Anciano , Suplementos Dietéticos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Lesiones Precancerosas/prevención & control , Modelos de Riesgos Proporcionales
5.
J Med Chem ; 64(4): 2151-2166, 2021 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-33534560

RESUMEN

In this study, we describe the development of heterobivalent [DUPA-6-Ahx-([111In]In-DO3A)-8-Aoc-BBN ANT] and [DUPA-6-Ahx-([177Lu]Lu-DO3A)-8-Aoc-BBN ANT] radiotracers that display very high selectivity/specificity for gastrin-releasing peptide receptor (GRPR)-/prostate-specific membrane antigen (PSMA)-expressing cells. These studies include metallation, purification, characterization, and in vitro and in vivo evaluation of the new small-molecule-/peptide-based radiopharmaceuticals having utility for imaging and potentially therapy. Competitive displacement binding assays using PC-3 cells and LNCaP cell membranes showed high binding affinity for the GRPR or the PSMA. Biodistribution studies showed favorable excretion pharmacokinetics with high tumor uptake in PC-3 or PC-3 prostatic inhibin peptide (PIP) tumor-bearing mice. For example, tumor accumulation at the 1 h time point ranged from (4.74 ± 0.90) to (7.51 ± 2.61)%ID/g. Micro-single-photon emission computed tomography (microSPECT) molecular imaging investigations showed very high uptake in tumors with minimal accumulation of tracers in the surrounding collateral tissues in xenografted mice at 4 h postintravenous injection. In conclusion, [DUPA-6-Ahx-([111In]In-DO3A)-8-Aoc-BBN ANT] and [DUPA-6-Ahx-([177Lu]Lu-DO3A)-8-Aoc-BBN ANT] tracers displayed favorable pharmacokinetic and excretion profiles with high uptake and retention in tumors.


Asunto(s)
Complejos de Coordinación/farmacología , Colorantes Fluorescentes/farmacología , Glutamato Carboxipeptidasa II/metabolismo , Glicoproteínas de Membrana/metabolismo , Radiofármacos/farmacología , Receptores de Bombesina/metabolismo , Animales , Antígenos de Superficie/metabolismo , Línea Celular Tumoral , Complejos de Coordinación/farmacocinética , Colorantes Fluorescentes/farmacocinética , Humanos , Radioisótopos de Indio/química , Lutecio/química , Masculino , Ratones , Oligopéptidos/farmacocinética , Oligopéptidos/farmacología , Medicina de Precisión/métodos , Radioisótopos/química , Radiofármacos/farmacocinética , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único
6.
Nucl Med Biol ; 94-95: 46-52, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33515899

RESUMEN

INTRODUCTION: With the long-term goal of developing a diagnostic (99mTc) and therapeutic (186Re) agent pair for targeting somatostatin receptor (SSTR)-positive neuroendocrine tumors (NETs), we developed novel metal-cyclized peptides through direct labeling of the potent SSTR2 antagonist Ac-4-NO2-Phe-c(DCys-Tyr-DTrp-Lys-Thr-Cys)-DTyr-NH2 (1) with Re (in Re-1), 99mTc (in [99mTc]Tc-1) and 186Re (in [186Re]Re-1). METHODS: Re-1 was characterized by LC-ESI-MS and HR-ESI-MS and was tested for receptor affinity in SSTR-expressing cells (AR42J). Radiolabeling of the peptide was achieved via ligand exchange from 99mTc-labeled glucoheptonate or [186Re]ReOCl3(PPh3)2, yielding [99mTc]Tc-1 or [186Re]Re-1, respectively. In vitro stability of [99mTc]Tc-1/[186Re]Re-1 in PBS (10 mM) at pH 7.4 and 37 °C was determined by HPLC analysis. Moreover, [99mTc]Tc-1 stability was tested in cysteine (1 mM) and rat serum under the same conditions. RESULTS: Re-1 consisted of two isomers, confirmed by LC-ESI-MS, with good SSTR2 affinity (IC50 = 43 ± 6 nM). Optimization of the 99mTc labeling through varying reaction parameters such as pH, reaction time, and Sn2+ and ligand concentrations resulted in high radiochemical yield (RCY ≥92%). Similarly, [186Re]Re-1 was prepared in reasonable RCY (≥50%). Both 99mTc/186Re-tracers consisted of two product isomers as identified by HPLC co-injection with Re-1. While [99mTc]Tc-1 was sufficiently stable in vitro (≥71% intact through 4 h in PBS, cysteine and rat serum), [186Re]Re-1 exhibited more moderate in vitro stability (58% intact after 1 h in PBS). CONCLUSIONS: Novel 99mTc/186Re-cyclized SSTR2 antagonist peptides were synthesized and characterized using the Re-cyclized analogue as a reference. Due to the nanomolar SSTR2 affinity of Re-1 and good in vitro stability of [99mTc]Tc-1, the latter shows early promise for development as a radiodiagnostic agent for SSTR-expressing NETs. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE: The 99mTc-cyclized complex showed promising in vitro properties, and future in vivo studies will determine the potential for translating such a design into the human clinic.


Asunto(s)
Compuestos de Organotecnecio/química , Péptidos/química , Radioisótopos/química , Renio/química , Animales , Ciclización , Marcaje Isotópico , Radioquímica , Ratas , Receptores de Somatostatina
7.
ACS Omega ; 5(44): 28615-28620, 2020 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-33195913

RESUMEN

We have developed structurally unique bifunctional chelators in the NETA, NE3TA, and DEPA series for potential radiopharmaceutical applications. As part of our continued research efforts to generate efficient bifunctional chelators for targeted radionuclide therapy and imaging of various diseases, we designed a scorpion-like chelator that is proposed to completely saturate the coordination spheres of Y(III) and Lu(III). We herein report the synthesis and evaluation of a new chelator (3p-C-NEPA) with 10 donor groups for complexation with ß-emitting radionuclides 90Y(III), 86Y(III), and 177Lu(III). The chelator was synthesized and evaluated for radiolabeling kinetics with the readily available radioisotopes 90Y and 177Lu, and the corresponding 90Y or 177Lu-radiolabeled complexes were evaluated for in vitro stability in human serum and in vivo complex stability in mice. The new chelator rapidly bound 90Y or 177Lu and formed a stable complex with the radionuclides. The new chelator 3p-C-NEPA radiolabeled with either 90Y or 177Lu remains stable in human serum without dissociation for 10 days. 177Lu-labeled 3p-C-NEPA produced a favorable in vivo biodistribution profile in normal mice.

8.
Metabol Open ; 6: 100031, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32812912

RESUMEN

AIMS: To assess whether meeting both fasting plasma glucose (FPG) and HbA1c criteria for prediabetes in people at high risk indicates with near certainty the presence of dysglycemia on repeat testing. METHODS: Observational study using data from Vitamin D and Type 2 Diabetes (D2d) study. HbA1c, FPG were measured at screening visit 1; FPG, HbA1c and 2 h plasma glucose (2hPG) measured at screening visit 2 (a median of 21 days later); participants classified as having normal glucose regulation (all 3 tests in normal range), prediabetes or diabetes (at least 1 of 3 tests in diabetes range). A predictive model was developed to estimate the probability of confirming dysglycemia and for detecting diabetes at screening visit 2 based on values of FPG and HbA1c at screening visit 1. RESULTS: Of 1271 participants who met both FPG and HbA1c criteria for prediabetes at screening visit 1, 98.6% exhibited dysglycemia (defined as prediabetes or diabetes) on repeat testing (84.5% were classified as having prediabetes, 14.1% were reclassified as having diabetes). Of those with diabetes, 62.6% were identified by 2hPG alone. CONCLUSIONS: Combined measurement of FPG and HbA1c is a reliable and reproducible measure to identify presence of dysglycemia among people at high risk. A prediction model is provided to help clinicians decide whether an oral glucose tolerance test will provide value in detecting diabetes based on the 2hPG criterion.

9.
J Clin Endocrinol Metab ; 105(3)2020 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-31965161

RESUMEN

OBJECTIVE: Fasting plasma glucose (FPG), 2-hour plasma glucose (2hPG) from a 75-g oral glucose tolerance test (OGTT) and glycated hemoglobin (HbA1c) can lead to different results when diagnosing prediabetes and diabetes. The Hemoglobin Glycation Index (HGI) quantifies the interindividual variation in glycation resulting in discrepancies between FPG and HbA1c. We used data from the Vitamin D and Type 2 Diabetes (D2d) study to calculate HGI, to identify HGI-associated variables, and to determine how HGI affects prediabetes and diabetes diagnosis. MEASUREMENTS: A linear regression equation [HbA1c (%) = 0.0164 × FPG (mg/dL) + 4.2] was derived using the screening cohort (n = 6829) and applied to calculate predicted HbA1c. This was subtracted from the observed HbA1c to determine HGI in the baseline cohort with 2hPG data (n = 3945). Baseline variables plus prediabetes and diabetes diagnosis by FPG, HbA1c, and 2hPG were compared among low, moderate, and high HGI subgroups. RESULTS: The proportion of women and Black/African American individuals increased from low to high HGI subgroups. Mean FPG decreased and mean HbA1c increased from low to high HGI subgroups, consistent with the HGI calculation; however, mean 2hPG was not significantly different among HGI subgroups. CONCLUSIONS: High HGI was associated with Black race and female sex as reported previously. The observation that 2hPG was not different across HGI subgroups suggests that variation in postprandial glucose is not a significant source of population variation in HGI. Exclusive use of HbA1c for diagnosis will classify more Black individuals and women as having prediabetes compared with using FPG or 2hPG.


Asunto(s)
Diabetes Mellitus Tipo 2/diagnóstico , Hemoglobina Glucada/análisis , Estado Prediabético/diagnóstico , Administración Oral , Anciano , Glucemia/análisis , Glucemia/metabolismo , Estudios de Cohortes , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/prevención & control , Suplementos Dietéticos , Ayuno/sangre , Femenino , Prueba de Tolerancia a la Glucosa , Indicadores de Salud , Humanos , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Estado Prediabético/dietoterapia , Factores de Riesgo , Vitamina D/administración & dosificación , Vitamina D/sangre
11.
N Engl J Med ; 381(6): 520-530, 2019 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-31173679

RESUMEN

BACKGROUND: Observational studies support an association between a low blood 25-hydroxyvitamin D level and the risk of type 2 diabetes. However, whether vitamin D supplementation lowers the risk of diabetes is unknown. METHODS: We randomly assigned adults who met at least two of three glycemic criteria for prediabetes (fasting plasma glucose level, 100 to 125 mg per deciliter; plasma glucose level 2 hours after a 75-g oral glucose load, 140 to 199 mg per deciliter; and glycated hemoglobin level, 5.7 to 6.4%) and no diagnostic criteria for diabetes to receive 4000 IU per day of vitamin D3 or placebo, regardless of the baseline serum 25-hydroxyvitamin D level. The primary outcome in this time-to-event analysis was new-onset diabetes, and the trial design was event-driven, with a target number of diabetes events of 508. RESULTS: A total of 2423 participants underwent randomization (1211 to the vitamin D group and 1212 to the placebo group). By month 24, the mean serum 25-hydroxyvitamin D level in the vitamin D group was 54.3 ng per milliliter (from 27.7 ng per milliliter at baseline), as compared with 28.8 ng per milliliter in the placebo group (from 28.2 ng per milliliter at baseline). After a median follow-up of 2.5 years, the primary outcome of diabetes occurred in 293 participants in the vitamin D group and 323 in the placebo group (9.39 and 10.66 events per 100 person-years, respectively). The hazard ratio for vitamin D as compared with placebo was 0.88 (95% confidence interval, 0.75 to 1.04; P = 0.12). The incidence of adverse events did not differ significantly between the two groups. CONCLUSIONS: Among persons at high risk for type 2 diabetes not selected for vitamin D insufficiency, vitamin D3 supplementation at a dose of 4000 IU per day did not result in a significantly lower risk of diabetes than placebo. (Funded by the National Institute of Diabetes and Digestive and Kidney Diseases and others; D2d ClinicalTrials.gov number, NCT01942694.).


Asunto(s)
Colecalciferol/uso terapéutico , Diabetes Mellitus Tipo 2/prevención & control , Suplementos Dietéticos , Estado Prediabético/tratamiento farmacológico , Vitaminas/uso terapéutico , Administración Oral , Anciano , Colecalciferol/administración & dosificación , Supervivencia sin Enfermedad , Método Doble Ciego , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Factores de Riesgo , Insuficiencia del Tratamiento , Vitamina D/análogos & derivados , Vitamina D/sangre , Vitaminas/administración & dosificación
12.
Arch Pathol Lab Med ; 143(6): 732-737, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30672336

RESUMEN

CONTEXT.­: The College of American Pathologists published guideline recommending bone marrow synoptic reporting for hematologic neoplasms. OBJECTIVE.­: To evaluate the impact of pathology-driven algorithmic testing (PDAT) with integrated reporting for bone marrow examination on test utilization, ability to render a specific World Health Organization diagnosis, and clinician satisfaction 1 year after implementation. DESIGN.­: We reviewed the hematopathology reports, integrated synoptic reports, and ancillary test results generated during a 12-month period. The initial diagnosis from the hematopathology report was compared with the final diagnosis on the integrated synoptic reports. Test utilization data were compared with a previous year in which ancillary testing was ordered at clinician discretion. Clinicians were anonymously surveyed to assess their satisfaction with PDAT and integrated reporting. RESULTS.­: Integrated reporting resulted in a World Health Organization diagnosis for 80 of 85 cases (94%) compared with 54 (64%) for the hematopathology report alone. Unnecessary testing decreased from 45% pre-PDAT (124 of 274 cases) to 0.7% PDAT (2 of 268 cases), and PDAT resulted in fewer omissions of necessary tests. Clinicians preferred PDAT and valued integrated reporting for a variety of reasons, including the ease of finding relevant prognostic information. CONCLUSIONS.­: Pathology-driven algorithmic testing with integrated reporting improves the pathologist's ability to render a specific World Health Organization diagnosis and improves test utilization. Clinicians prefer PDAT to clinician-ordered testing. This is the first study to examine how synoptic reporting can modify hematologic diagnoses.


Asunto(s)
Algoritmos , Examen de la Médula Ósea/normas , Neoplasias Hematológicas/diagnóstico , Patología Clínica/métodos , Patología Clínica/normas , Humanos , Informe de Investigación/normas
13.
Bioorg Med Chem ; 27(3): 492-501, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30594453

RESUMEN

The somatostatin receptor subtype 2 (SSTR2) is often highly expressed on neuroendocrine tumors (NETs), making it a popular in vivo target for diagnostic and therapeutic approaches aimed toward management of NETs. In this work, an antagonist peptide (sst2-ANT) with high affinity for SSTR2 was modified at the N-terminus with a novel [N,S,O] bifunctional chelator (2) designed for tridentate chelation of rhenium(I) and technetium(I) tricarbonyl cores, [Re(CO)3]+ and [99mTc][Tc(CO)3]+. The chelator-peptide conjugation was performed via a Cu(I)-assisted click reaction of the alkyne-bearing chelator (2) with an azide-functionalized sst2-ANT peptide (3), to yield NSO-sst2-ANT (4). Two synthetic methods were used to prepare Re-4 at the macroscopic scale, which differed based on the relative timing of the click conjugation to the [Re(CO)3]+ complexation by 2. The resulting products demonstrated the expected molecular mass and nanomolar in vitro SSTR2 affinity (IC50 values under 30 nM, AR42J cells, [125I]iodo-Tyr11-somatostatin-14 radioligand standard). However, a difference in their HPLC retention times suggested a difference in metal coordination modes, which was attributed to a competing N-triazole donor ligand formed during click conjugation. Surprisingly, the radiotracer scale reaction of [99mTc][Tc(OH2)3(CO)3]+ (99mTc; t½â€¯= 6 h, 141 keV γ) with 4 formed a third product, distinct from the Re analogues, making this one of the unusual cases in which Re and Tc chemistries are not well matched. Nevertheless, the [99mTc]Tc-4 product demonstrated excellent in vitro stability to challenges by cysteine and histidine (≥98% intact through 24 h), along with 75% stability in mouse serum through 4 h. In vivo biodistribution and microSPECT/CT imaging studies performed in AR42J tumor-bearing mice revealed improved clearance of this radiotracer in comparison to a similar [99mTc][Tc(CO)3]-labeled sst2-ANT derivative previously studied. Yet despite having adequate tumor uptake at 1 h (4.9% ID/g), tumor uptake was not blocked by co-administration of a receptor-saturating dose of SS-14. Aimed toward realignment of the Re and Tc product structures, future efforts should include distancing the alkyne group from the intended donor atoms of the chelator, to reduce the coordination options available to the [M(CO)3]+ core (M = Re, 99mTc) by disfavoring involvement of the N-triazole.


Asunto(s)
Quelantes/farmacología , Compuestos Organometálicos/farmacología , Radiofármacos/farmacología , Receptores de Somatostatina/antagonistas & inhibidores , Renio/farmacología , Tecnecio/farmacología , Animales , Línea Celular Tumoral , Quelantes/síntesis química , Quelantes/química , Relación Dosis-Respuesta a Droga , Femenino , Ratones , Ratones Endogámicos ICR , Ratones SCID , Estructura Molecular , Neoplasias Experimentales/diagnóstico por imagen , Neoplasias Experimentales/metabolismo , Imagen Óptica , Compuestos Organometálicos/síntesis química , Compuestos Organometálicos/química , Radiofármacos/síntesis química , Radiofármacos/química , Ratas , Receptores de Somatostatina/metabolismo , Renio/química , Relación Estructura-Actividad , Tecnecio/química , Distribución Tisular
14.
J Card Fail ; 25(1): 67-71, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30026129

RESUMEN

BACKGROUND: Diastolic dysfunction and heart failure with preserved ejection fraction (HFpEF) are associated with myocardial fibrosis and concentric left ventricular hypertrophy (LVH). In a preclinical model of LVH, we demonstrated that a moderate increase in heart rate can reduce interstitial fibrosis and improve LV compliance. We therefore hypothesized that moderately elevated heart rates can be used to beneficially modify the myocardial substrate in patients with diastolic dysfunction and HFpEF. As a preliminary step to test this hypothesis, we evaluated if patients can tolerate this novel pacemaker-based treatment approach without adverse effects. METHODS AND RESULTS: A pacemaker-mediated increase in heart rate to 100 beats/min for 5 hours at night was tested over 4 weeks in 10 patients with diastolic dysfunction. The patients underwent a physical examination, biomarker collection, 6-minute walk test, heart failure questionnaire, and echocardiography before and after the pacing intervention. None of the patients reported any symptoms at night. No arrhythmias were induced. Eight patients completed the protocol. Three patients experienced unanticipated daytime pacing from an interfering pacemaker function. There were no detrimental changes in biomarkers or LV systolic function. CONCLUSIONS: Nocturnal pacing at a rate of 100 beats/min appears to be safe and well tolerated in this small exploratory patient cohort.


Asunto(s)
Ritmo Circadiano/fisiología , Insuficiencia Cardíaca/terapia , Frecuencia Cardíaca/fisiología , Marcapaso Artificial , Volumen Sistólico/fisiología , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Femenino , Insuficiencia Cardíaca/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Método Simple Ciego , Resultado del Tratamiento
15.
Adv Exp Med Biol ; 1096: 135-158, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30324352

RESUMEN

Given the high incidence of prostate cancer, there is a continuing need for advances in early detection and in effective treatments. Over the last several years, radiolabeled peptides have been developed, which can target receptors on prostate tumors with high affinity and specificity. These peptides are eliminated from normal tissues rapidly, producing high contrast for PET and SPECT imaging. Receptors of interest for tumor imaging include prostate specific membrane antigen (PSMA), gastrin-releasing peptide receptor (GRPR), and αvß3 integrin. Because radiolabeled peptides afford high tumor-to-normal tissue uptake ratios, the potential of peptide-based targeted radiotherapy of prostate cancer is being explored. In addition, targeting either of two receptors with one peptide may allow more tumors to be detected and aid in the delineation of early versus advanced disease. Taken together, all these developments in peptide-based imaging and therapy of prostate cancer offer the promise of personalized, molecular medicine for individual patients.


Asunto(s)
Imagen Molecular , Péptidos/química , Neoplasias de la Próstata/diagnóstico por imagen , Radiofármacos/química , Antígenos de Superficie , Glutamato Carboxipeptidasa II , Humanos , Integrina alfaVbeta3 , Masculino , Tomografía de Emisión de Positrones , Receptores de Bombesina , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único
16.
Mol Imaging ; 17: 1536012118790065, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30064304

RESUMEN

The goal of these studies was to use a tumor-targeting, near-infrared (NIR) fluorescent peptide to evaluate early detection and to guide surgical removal of polyps in a genetically engineered rat model of spontaneous colorectal cancer. This peptide, LS301, was conjugated to Cy7.5 and applied topically to the colon of adenoma-bearing Pirc rats. Ten minutes after administration, rats underwent targeted NIR laser colonoscopy. Rats were also evaluated by white light colonoscopy and narrow-band imaging, for comparison to the NIR technique. Unlike white light and narrow-band colonoscopy, NIR imaging detected unexpected flat lesions in young Pirc rats. NIR imaging was also used to assess resection margins after electrocauterization of polyps. Tumor margins remained negative at 5 weeks postsurgery, demonstrating successful polypectomy. The present studies show that NIR-targeted colonoscopy is an attractive strategy to improve screening for and resection of colorectal neoplasia.


Asunto(s)
Pólipos del Colon/diagnóstico , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer/métodos , Péptidos/química , Espectroscopía Infrarroja Corta , Animales , Pólipos del Colon/cirugía , Modelos Animales de Enfermedad , Fluorescencia , Ratas
17.
Am J Clin Pathol ; 150(5): 393-405, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-30052721

RESUMEN

OBJECTIVES: To assess bone marrow (BM) sampling in academic medical centers. METHODS: Data from 6,374 BM samples obtained in 32 centers in 2001 and 2011, including core length (CL), were analyzed. RESULTS: BM included a biopsy (BMB; 93%) specimen, aspirate (BMA; 92%) specimen, or both (83%). The median (SD) CL was 12 (8.5) mm, and evaluable marrow was 9 (7.6) mm. Tissue contraction due to processing was 15%. BMB specimens were longer in adults younger than 60 years, men, and bilateral, staging, and baseline samples. Only 4% of BMB and 2% of BMB/BMA samples were deemed inadequate for diagnosis. BM for plasma cell dyscrasias, nonphysician operators, and ancillary studies usage increased, while bilateral sampling decreased over the decade. BM-related quality assurance programs are infrequent. CONCLUSIONS: CL is shorter than recommended and varies with patient age and sex, clinical circumstances, and center experience. While pathologists render diagnoses on most cases irrespective of CL, BMB yield improvement is desirable.


Asunto(s)
Enfermedades de la Médula Ósea/patología , Médula Ósea/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Biopsia con Aguja Gruesa , Enfermedades de la Médula Ósea/diagnóstico , Examen de la Médula Ósea/normas , Canadá , Niño , Preescolar , Estudios Transversales , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Estados Unidos , Adulto Joven
18.
Diabetes Care ; 41(8): 1590-1599, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29941495

RESUMEN

OBJECTIVE: To describe baseline characteristics of the Vitamin D and Type 2 Diabetes (D2d) study, the first large U.S. diabetes prevention clinical trial to apply current American Diabetes Association (ADA) criteria for prediabetes. RESEARCH DESIGN AND METHODS: This is a multicenter (n = 22 sites), randomized, double-blind, placebo-controlled, primary prevention clinical trial testing effects of oral daily 4,000 IU cholecalciferol (D3) compared with placebo on incident diabetes in U.S. adults at risk for diabetes. Eligible participants were at risk for diabetes, defined as not meeting criteria for diabetes but meeting at least two 2010 ADA glycemic criteria for prediabetes: fasting plasma glucose (FPG) 100-125 mg/dL, 2-h postload glucose (2hPG) after a 75-g oral glucose load 140-199 mg/dL, and/or a hemoglobin A1c (HbA1c) 5.7-6.4% (39-46 mmol/mol). RESULTS: A total of 2,423 participants (45% of whom were women and 33% nonwhite) were randomized to cholecalciferol or placebo. Mean (SD) age was 59 (9.9) years and BMI 32 (4.5) kg/m2. Thirty-five percent met all three prediabetes criteria, 49% met the FPG/HbA1c criteria only, 9.5% met the 2hPG/FPG criteria only, and 6.3% met the 2hPG/HbA1c criteria only. Black participants had the highest mean HbA1c and lowest FPG concentration compared with white, Asian, and other races (P < 0.01); 2hPG concentration did not differ among racial groups. When compared with previous prediabetes cohorts, the D2d cohort had lower mean 2hPG concentration but similar HbA1c and FPG concentrations. CONCLUSIONS: D2d will establish whether vitamin D supplementation lowers risk of diabetes and will inform about the natural history of prediabetes per contemporary ADA criteria.


Asunto(s)
Colecalciferol/uso terapéutico , Diabetes Mellitus Tipo 2/prevención & control , Estado Prediabético/tratamiento farmacológico , Vitamina D/sangre , Adulto , Anciano , Anciano de 80 o más Años , Glucemia/metabolismo , Estudios de Cohortes , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/epidemiología , Suplementos Dietéticos , Método Doble Ciego , Femenino , Hemoglobina Glucada/análisis , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estado Prediabético/sangre , Estado Prediabético/diagnóstico , Estado Prediabético/epidemiología
19.
J Clin Endocrinol Metab ; 103(2): 681-688, 2018 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-29253154

RESUMEN

Context: Studies of the possible cardiovascular risk of testosterone treatment are inconclusive. Objective: To determine the effect of testosterone treatment on cardiovascular biomarkers in older men with low testosterone. Design: Double-blind, placebo-controlled trial. Setting: Twelve academic medical centers in the United States. Participants: In all, 788 men ≥65 years old with an average of two serum testosterone levels <275 ng/dL who were enrolled in The Testosterone Trials. Intervention: Testosterone gel, the dose adjusted to maintain the testosterone level in the normal range for young men, or placebo gel for 12 months. Main Outcome Measures: Serum markers of cardiovascular risk, including lipids and markers of glucose metabolism, fibrinolysis, inflammation, and myocardial damage. Results: Compared with placebo, testosterone treatment significantly decreased total cholesterol (adjusted mean difference, -6.1 mg/dL; P < 0.001), high-density lipoprotein cholesterol (adjusted mean difference, -2.0 mg/dL; P < 0.001), and low-density lipoprotein cholesterol (adjusted mean difference, -2.3 mg/dL; P = 0.051) from baseline to month 12. Testosterone also slightly but significantly decreased fasting insulin (adjusted mean difference, -1.7 µIU/mL; P = 0.02) and homeostatic model assessment‒insulin resistance (adjusted mean difference, -0.6; P = 0.03). Testosterone did not change triglycerides, d-dimer, C-reactive protein, interleukin 6, troponin, glucose, or hemoglobin A1c levels more than placebo. Conclusions and Relevance: Testosterone treatment of 1 year in older men with low testosterone was associated with small reductions in cholesterol and insulin but not with other glucose markers, markers of inflammation or fibrinolysis, or troponin. The clinical importance of these findings is unclear and requires a larger trial of clinical outcomes.


Asunto(s)
Biomarcadores/sangre , Sistema Cardiovascular/efectos de los fármacos , Sistema Cardiovascular/metabolismo , Testosterona/farmacología , Anciano , Anciano de 80 o más Años , Envejecimiento/sangre , Envejecimiento/efectos de los fármacos , Sistema Cardiovascular/fisiopatología , Método Doble Ciego , Terapia de Reemplazo de Hormonas , Humanos , Hipogonadismo/sangre , Hipogonadismo/tratamiento farmacológico , Hipogonadismo/fisiopatología , Masculino , Testosterona/sangre , Estados Unidos
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