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1.
Clin Transl Med ; 14(3): e1627, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38515274

RESUMEN

PURPOSE: Our preclinical studies showed that lycopene enhanced the anti-prostate cancer efficacy of docetaxel in animal models. A phase I trial (NCT0149519) was conducted to identify an optimum dose of synthetic lycopene in combination with docetaxel (and androgen blockade [androgen deprivation therapy, ADT]), and to evaluate its effect on the safety and pharmacokinetics of docetaxel in men with metastatic prostate cancer. METHODS: Subjects were treated with 21-day cycles of 75 mg/m2 docetaxel (and ADT), plus lycopene at 30, 90 or 150 mg/day. A Bayesian model averaging continual reassessment method was used to guide dose escalation. Pharmacokinetics of docetaxel and multiple correlative studies were carried out. RESULTS: Twenty-four participants were enrolled, 18 in a dose escalation cohort to define the maximum tolerated dose (MTD), and six in a pharmacokinetic cohort. Docetaxel/ADT plus 150 mg/day synthetic lycopene resulted in dose-limiting toxicity (pulmonary embolus) in one out of 12 participants with an estimated probability of .106 and thus was chosen as the MTD. Lycopene increased the AUCinf and Cmax of plasma docetaxel by 9.5% and 15.1%, respectively. Correlative studies showed dose-related changes in circulating endothelial cells and vascular endothelial growth factor A, and reduction in insulin-like growth factor 1R phosphorylation, associated with lycopene therapy. CONCLUSIONS: The combination of docetaxel/ADT and synthetic lycopene has low toxicity and favourable pharmacokinetics. The effects of lycopene on biomarkers provide additional support for the toxicity-dependent MTD definition. HIGHLIGHTS: The maximum tolerated dose was identified as 150 mg/day of lycopene in combination with docetaxel/ADT for the treatment of metastatic prostate cancer patients. Small increases in plasma exposure to docetaxel were observed with lycopene co-administration. Mechanistically significant effects were seen on angiogenesis and insulin-like growth factor 1 signalling by lycopene co-administration with docetaxel/ADT.


Asunto(s)
Neoplasias de la Próstata , Masculino , Humanos , Docetaxel , Neoplasias de la Próstata/tratamiento farmacológico , Neoplasias de la Próstata/patología , Licopeno/uso terapéutico , Factor A de Crecimiento Endotelial Vascular , Antagonistas de Andrógenos/uso terapéutico , Andrógenos/uso terapéutico , Teorema de Bayes , Células Endoteliales/patología
2.
Cancers (Basel) ; 15(7)2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-37046763

RESUMEN

After potentially curative treatment, colorectal cancer (CRC) patients remain at high risk for recurrence, second primary CRC, and high-risk adenomas. In combination with existing data, our previous findings provide a rationale for reducing tissue polyamines as tertiary prevention in non-metastatic CRC patients. The goal of this study was to demonstrate rectal tissue polyamine reduction in optimally treated stage I-III CRC patients after intervention with daily oral aspirin + dietary arginine restriction. A single-institution phase IIa clinical trial was conducted. Patients were treated with aspirin 325 mg/day and an individualized dietary regimen designed to reduce arginine intake by ≥30% over a 12-week study period. Dietary intake, endoscopy with rectal biopsies, and phlebotomy were performed pre- and post-intervention. The primary endpoint was to demonstrate ≥50% decrease in rectal tissue putrescine levels from baseline as a measure of polyamine reduction in the target tissue. Twenty eligible patients completed the study. After study intervention, mean dietary arginine intake decreased from 3.7 g/day ± 1.3 SD to 2.6 g/day ± 1.2 SD (29.7% decrease, p < 0.02 by Sign test). Mean plasma arginine levels decreased from 46.0 ng/mL ± 31.5 SD at baseline to 35 ng/mL ± 21.7 SD (p < 0.001). Rectal tissue putrescine levels were 0.90 nMol/mg-protein pre-intervention and 0.99 nMol/mg-protein post-intervention (p < 0.64, NS). No significant differences were observed for the other tissue polyamines investigated: spermidine (p < 0.13), spermine (p < 0.21), spermidine:spermine ratio (p < 0.71). Among CRC survivors, treatment with daily oral aspirin and an individualized dietary arginine restriction intervention resulted in lower calculated dietary arginine intake and plasma arginine levels but did not affect rectal tissue polyamine levels.

3.
Blood Cells Mol Dis ; 85: 102463, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32652459

RESUMEN

Glyceronephosphate O-acyltransferase (GNPAT) p.D519G (rs11558492) was identified as a genetic modifier correlated with more severe iron overload in hemochromatosis through whole-exome sequencing of HFE p.C282Y homozygotes with extreme iron phenotypes. We studied the prevalence of p.D519G in HFE p.C282Y/p.H63D compound heterozygotes, a genotype associated with iron overload in some patients. Cases were Australian participants with elevated serum ferritin (SF) levels ≥300µg/L (males) and ≥200µg/L (females); subjects whose SF levels were below these cut-offs were designated as controls. Samples were genotyped for GNPAT p.D519G. We compared the allele frequency of the present subjects, with/without elevated SF, to p.D519G frequency in public datasets. GNPAT p.D519G was more prevalent in our cohort of p.C282Y/p.H63D compound heterozygotes with elevated SF (37%) than European public datasets: 1000G 21%, gnomAD 20% and ESP 21%. We conclude that GNPAT p.D519G is associated with elevated SF in Australian HFE p.C282Y/p.H63D compound heterozygotes.


Asunto(s)
Aciltransferasas/genética , Proteína de la Hemocromatosis/genética , Hemocromatosis/genética , Mutación Puntual , Adulto , Femenino , Ferritinas/sangre , Hemocromatosis/sangre , Heterocigoto , Humanos , Masculino , Persona de Mediana Edad
4.
PLoS One ; 15(4): e0232125, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32324809

RESUMEN

BACKGROUND: Few cross-sectional studies report iron deficiency (ID) prevalence in women of different race/ethnicity and ages in US or Canada. MATERIALS AND METHODS: We evaluated screening observations on women who participated between 2001-2003 in a cross-sectional, primary care-based sample of adults ages ≥25 y whose observations were complete: race/ethnicity; age; transferrin saturation; serum ferritin; and HFE p.C282Y and p.H63D alleles. We defined ID using a stringent criterion: combined transferrin saturation <10% and serum ferritin <33.7 pmol/L (<15 µg/L). We compared ID prevalence in women of different race/ethnicity subgrouped by age and determined associations of p.C282Y and p.H63D to ID overall, and to ID in women ages 25-44 y with or without self-reported pregnancy. RESULTS: These 62,685 women included 27,079 whites, 17,272 blacks, 8,566 Hispanics, 7,615 Asians, 449 Pacific Islanders, 441 Native Americans, and 1,263 participants of other race/ethnicity. Proportions of women with ID were higher in Hispanics and blacks than whites and Asians. Prevalence of ID was significantly greater in women ages 25-54 y of all race/ethnicity groups than women ages ≥55 y of corresponding race/ethnicity. In women ages ≥55 y, ID prevalence did not differ significantly across race/ethnicity. p.C282Y and p.H63D prevalence did not differ significantly in women with or without ID, regardless of race/ethnicity, age subgroup, or pregnancy. CONCLUSIONS: ID prevalence was greater in Hispanic and black than white and Asian women ages 25-54 y. p.C282Y and p.H63D prevalence did not differ significantly in women with or without ID, regardless of race/ethnicity, age subgroup, or pregnancy.


Asunto(s)
Anemia Ferropénica/epidemiología , Etnicidad/clasificación , Ferritinas/sangre , Proteína de la Hemocromatosis/genética , Transferrina/análisis , Adulto , Anciano , Anemia Ferropénica/genética , Anemia Ferropénica/metabolismo , Canadá/epidemiología , Estudios Transversales , Etnicidad/genética , Femenino , Humanos , Persona de Mediana Edad , Mutación , Prevalencia , Estados Unidos/epidemiología
5.
Cardiovasc Endocrinol Metab ; 9(1): 9-16, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32104786

RESUMEN

In epidemiology studies, identification of diabetes type (type 1 vs. type 2) among study participants with diabetes is important; however, conventional diabetes type identification approaches that include age at diabetes diagnosis as an initial criterion introduces biases. Using data from the National Health and Nutrition Examination Survey, we have developed a novel algorithm which does not include age at diagnosis to identify participants with self-reported diagnosed diabetes as having type 1 vs. type 2 diabetes. METHODS: A total of 5457 National Health and Nutrition Examination Survey participants between cycles 1999-2000 and 2015-2016 reported that a health professional had diagnosed them as having diabetes at a time other than during pregnancy and had complete information on diabetes-related questions. After developing an algorithm based on information regarding the treatment(s) they received, we classified these participants as having type 1 or type 2 diabetes. RESULTS: The treatment-based algorithm yielded a 6-94% split for type 1 and type 2 diabetes, which is consistent with reports from the Centers for Disease Control and other resources. Moreover, the demographics and clinical characteristics of the assigned type 1 and type 2 cases were consistent with contemporary epidemiologic findings. CONCLUSION: Applying diabetes treatment information from the National Health and Nutrition Examination Survey, as formulated in our treatment-based algorithm, may better identify type 1 and type 2 diabetes cases and thus prevent the specific biases imposed by conventional approaches which include the age of diabetes diagnosis as an initial criterion for diabetes type classification.

6.
Cancer Prev Res (Phila) ; 13(2): 203-212, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31818851

RESUMEN

Obesity is associated with risk of colorectal adenoma (CRA) and colorectal cancer. The signaling pathway activated by metformin (LKB1/AMPK/mTOR) is implicated in tumor suppression in ApcMin/+ mice via metformin-induced reduction in polyp burden, increased ratio of pAMPK/AMPK, decreased pmTOR/mTOR ratio, and decreased pS6Ser235/S6Ser235 ratio in polyps. We hypothesized that metformin would affect colorectal tissue S6Ser235 among obese patients with recent history of CRA. A phase IIa clinical biomarker trial was conducted via the U.S. National Cancer Institute-Chemoprevention Consortium. Nondiabetic, obese subjects (BMI ≥30) ages 35 to 80 with recent history of CRA were included. Subjects received 12 weeks of oral metformin 1,000 mg twice every day. Rectal mucosa biopsies were obtained at baseline and end-of-treatment (EOT) endoscopy. Tissue S6Ser235 and Ki-67 immunostaining were analyzed in a blinded fashion using Histo score (Hscore) analysis. Among 32 eligible subjects, the mean baseline BMI was 34.9. Comparing EOT to baseline tissue S6Ser235 by IHC, no significant differences were observed. Mean (SD) Hscore at baseline was 1.1 (0.57) and 1.1 (0.51) at EOT; median Hscore change was 0.034 (P = 0.77). Similarly, Ki-67 levels were unaffected by the intervention. The adverse events were consistent with metformin's known side-effect profile. Among obese patients with CRA, 12 weeks of oral metformin does not reduce rectal mucosa pS6 or Ki-67 levels. Further research is needed to determine what effects metformin has on the target tissue of origin as metformin continues to be pursued as a colorectal cancer chemopreventive agent.


Asunto(s)
Adenoma/patología , Pólipos del Colon/patología , Neoplasias Colorrectales/prevención & control , Metformina/administración & dosificación , Obesidad/complicaciones , Adenoma/complicaciones , Administración Oral , Anciano , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/metabolismo , Biopsia , Índice de Masa Corporal , Pólipos del Colon/complicaciones , Colonoscopía , Neoplasias Colorrectales/etiología , Neoplasias Colorrectales/patología , Femenino , Humanos , Mucosa Intestinal/diagnóstico por imagen , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Intestino Grueso/diagnóstico por imagen , Intestino Grueso/efectos de los fármacos , Intestino Grueso/patología , Masculino , Metformina/efectos adversos , Persona de Mediana Edad , Obesidad/diagnóstico , Proctoscopía , Recto/diagnóstico por imagen , Recto/efectos de los fármacos , Recto/patología
7.
J Biomed Opt ; 24(5): 1-8, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-31124346

RESUMEN

Relatively few imaging and sensing technologies are employed to study human lactation physiology. In particular, human mammary development during pregnancy as well as mammary involution after lactation have been poorly described, despite their importance for breast cancer diagnosis and treatment during these phases. Our case study shows the potential of diffuse optical spectroscopic imaging (DOSI) to uniquely study the spatiotemporal changes in mammary tissue composition during the involution of the lactating breast toward its pre-pregnant state. At nine time intervals over a period of eight months after the cessation of breastfeeding, we reconstructed 2-D maps of mammary water content, lipid content, total hemoglobin (THb) concentration, oxygen saturation (StO2), and tissue optical scattering. Mammary lipid content in the nonareolar region showed a significant relative increase of 59%, whereas water content and THb concentration showed a significant relative decrease of 50% and 48%, respectively. Significant changes were also found in StO2 and tissue optical scattering. Our findings are consistent with the gradual replacement of fibroglandular tissue by adipose tissue and vascular regression during mammary involution. Moreover, our data provide unique insight into the dynamics of breast tissue composition and demonstrate the effectiveness of DOSI as a technique to study human lactation physiology.


Asunto(s)
Mama/diagnóstico por imagen , Mama/fisiología , Lactancia/fisiología , Imagen Óptica/métodos , Adulto , Lactancia Materna , Femenino , Hemoglobinas/análisis , Humanos , Procesamiento de Imagen Asistido por Computador , Lípidos/química , Imagen por Resonancia Magnética , Oxígeno/metabolismo , Seguridad del Paciente , Dispersión de Radiación , Espectrofotometría
8.
PLoS One ; 14(3): e0214196, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30913256

RESUMEN

Homozygosity for the p.C282Y substitution in the HFE protein encoded by the hemochromatosis gene on chromosome 6p (HFE) is a common genetic trait that increases susceptibility to iron overload. McLaren et al. used bivariate mixture modeling to analyze the joint population distribution of transferrin saturation (TS) and serum ferritin concentration (SF) measured for participants in the Hemochromatosis and Iron Overload Screening (HEIRS) Study. They identified four components (C1, C2, C3, and C4) with successively increasing means for TS and SF. They demonstrated that bivariate mixture modeling in TS and SF reflect the genetic locus of HFE and may isolate p.C282Y homozygotes from the general population. In the current study we used data from the another large cohort, the Australian HealthIron study of genetic and environmental modifiers of hereditary hemochromatosis, to validate the component analysis approach, to examine stability of component proportions over time and to determine if TS and SF values from an individual move between components at baseline and follow-up. Because sampling fractions from each p.C282Y / p.H63D genotype stratum are not equal, we used frequency weights based on the inverse of the probability of selection for invitation to participate. In the weighted female analytic cohorts, C4 captured most of C282Y homozygotes, and C2 was the largest component. We identified four components from the weighted male analytic cohort and C4 captured most of p.C282Y homozygotes. The bivariate mixture modeling approach suggested that the model is transferable from one white population to another, although estimated means within components may differ.


Asunto(s)
Ferritinas/sangre , Proteína de la Hemocromatosis/genética , Homocigoto , Modelos Biológicos , Transferrina/metabolismo , Adulto , Sustitución de Aminoácidos , Australia , Femenino , Hemocromatosis/sangre , Hemocromatosis/genética , Humanos , Masculino , Persona de Mediana Edad , Mutación Missense
9.
Ann Hepatol ; 17(5): 871-879, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-30145563

RESUMEN

INTRODUCTION AND AIM: We sought to identify independent risk factors for cirrhosis in HFE p.C282Y homozygotes in a cross-sectional study. MATERIAL AND METHODS: We evaluated 368 p.C282Y homozygotes who underwent liver biopsy and compared characteristics of those with and without cirrhosis. We performed multivariable logistic regression on cirrhosis with: age; sex; race/ethnicity; diabetes; blood pints/units donated voluntarily; erythrocyte pints/units received; iron supplement use; alcohol intake, g/d; body mass index, kg/m2; swollen/tender 2nd/3rd metacarpophalangeal joints; elevated alanine aminotransferase; elevated aspartate aminotransferase; steatosis/fatty liver; iron removed by phlebotomy, g; and GNPAT p.D519G positivity. RESULTS: Mean age of 368 participants (73.6% men) was 47 ± 13 (standard deviation) y. Cirrhosis was diagnosed in 86 participants (23.4%). Participants with cirrhosis had significantly greater mean age, proportion of men, diabetes prevalence, mean daily alcohol intake, prevalence of swollen/ tender 2nd/3rd metacarpophalangeal joints, mean serum ferritin, elevated alanine aminotransferase, elevated aspartate aminotransferase, and mean iron removed; and significantly fewer mean blood pints/units donated. GNPAT p.D519G positivity was detected in 82 of 188 participants (43.6%). In a multivariable model for cirrhosis, there were four significant positive associations: age (10-y intervals) (odds ratio 2.2 [95% confidence interval 1.5, 3.3]); diabetes (3.3; [1.1, 9.7]); alcohol intake (14 g alcohol drinks/d) (1.5 [1.2, 1.8]); and iron removed, g (1.3 [1.2, 1.4]). There was no statistical evidence of two-way interactions between these variables. CONCLUSION: In conclusion, cirrhosis in HFE p.C282Y homozygotes is significantly associated with age, diabetes, daily alcohol intake, and iron removed by phlebotomy, taking into account the effect of other variables.


Asunto(s)
Proteína de la Hemocromatosis/genética , Hemocromatosis/genética , Homocigoto , Cirrosis Hepática/genética , Mutación , Aciltransferasas/genética , Adulto , Factores de Edad , Consumo de Bebidas Alcohólicas/efectos adversos , Consumo de Bebidas Alcohólicas/epidemiología , Australia/epidemiología , Comorbilidad , Estudios Transversales , Diabetes Mellitus/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Hemocromatosis/diagnóstico , Hemocromatosis/epidemiología , Hemocromatosis/terapia , Humanos , Cirrosis Hepática/epidemiología , Cirrosis Hepática/patología , Masculino , Persona de Mediana Edad , Fenotipo , Flebotomía , Polimorfismo de Nucleótido Simple , Prevalencia , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiología
10.
Mil Med ; 183(suppl_1): 150-156, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29635570

RESUMEN

Objective: To quantitatively measure tissue composition and hemodynamics during resuscitative endovascular balloon occlusion of the aorta (REBOA) in two tissue compartments using non-invasive two-channel broadband diffuse optical spectroscopy (DOS). Methods: Tissue concentrations of oxy- and deoxyhemoglobin (HbO2 and HbR), water, and lipid were measured in a porcine model (n = 10) of massive hemorrhage (65% total blood volume over 1 h) and 30-min REBOA superior and inferior to the aortic balloon. Results: After hemorrhage, hemoglobin oxygen saturation (StO2 = HbO2/[HbO2 + HbR]) at both sites decreased significantly (-29.9% and -42.3%, respectively). The DOS measurements correlated with mean arterial pressure (MAP) (R2 = 0.79, R2 = 0.88), stroke volume (SV) (R2 = 0.68, R2 = 0.88), and heart rate (HR) (R2 = 0.72, R2 = 0.88). During REBOA, inferior StO2 continued to decline while superior StO2 peaked 12 min after REBOA before decreasing again. Inferior DOS parameters did not associate with MAP, SV, or HR during REBOA. Conclusions: Dual-channel regional tissue DOS measurements can be used to non-invasively track the formation of hemodynamically distinct tissue compartments during hemorrhage and REBOA. Conventional systemic measures MAP, HR, and SV are uncorrelated with tissue status in inferior (downstream) sites. Multi-compartment DOS may provide a more complete picture of the efficacy of REBOA and similar resuscitation procedures.


Asunto(s)
Procedimientos Endovasculares/instrumentación , Hemorragia/cirugía , Resucitación/normas , Análisis Espectral/métodos , Animales , Aorta/cirugía , Modelos Animales de Enfermedad , Procedimientos Endovasculares/métodos , Hemoglobinas/análisis , Oxihemoglobinas/análisis , Calidad de la Atención de Salud , Resucitación/métodos , Análisis Espectral/instrumentación , Porcinos/cirugía
11.
Nat Rev Dis Primers ; 4: 18016, 2018 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-29620054

RESUMEN

Haemochromatosis is defined as systemic iron overload of genetic origin, caused by a reduction in the concentration of the iron regulatory hormone hepcidin, or a reduction in hepcidin-ferroportin binding. Hepcidin regulates the activity of ferroportin, which is the only identified cellular iron exporter. The most common form of haemochromatosis is due to homozygous mutations (specifically, the C282Y mutation) in HFE, which encodes hereditary haemochromatosis protein. Non-HFE forms of haemochromatosis due to mutations in HAMP, HJV or TFR2 are much rarer. Mutations in SLC40A1 (also known as FPN1; encoding ferroportin) that prevent hepcidin-ferroportin binding also cause haemochromatosis. Cellular iron excess in HFE and non-HFE forms of haemochromatosis is caused by increased concentrations of plasma iron, which can lead to the accumulation of iron in parenchymal cells, particularly hepatocytes, pancreatic cells and cardiomyocytes. Diagnosis is noninvasive and includes clinical examination, assessment of plasma iron parameters, imaging and genetic testing. The mainstay therapy is phlebotomy, although iron chelation can be used in some patients. Hepcidin supplementation might be an innovative future approach.


Asunto(s)
Hemocromatosis/complicaciones , Hemocromatosis/terapia , Proteínas de Transporte de Catión/toxicidad , Terapia por Quelación/métodos , Hemocromatosis/epidemiología , Humanos , Hierro/toxicidad , Imagen por Resonancia Magnética/métodos , Tamizaje Masivo/métodos , Flebotomía/métodos , Polimorfismo Genético/genética , Calidad de Vida/psicología
12.
J Immunol ; 199(1): 186-203, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28539429

RESUMEN

HSV type 1 (HSV-1) is a prevalent human pathogen that infects >3.72 billion individuals worldwide and can cause potentially blinding recurrent corneal herpetic disease. HSV-1 establishes latency within sensory neurons of trigeminal ganglia (TG), and TG-resident CD8+ T cells play a critical role in preventing its reactivation. The repertoire, phenotype, and function of protective CD8+ T cells are unknown. Bolstering the apparent feeble numbers of CD8+ T cells in TG remains a challenge for immunotherapeutic strategies. In this study, a comprehensive panel of 467 HLA-A*0201-restricted CD8+ T cell epitopes was predicted from the entire HSV-1 genome. CD8+ T cell responses to these genome-wide epitopes were compared in HSV-1-seropositive symptomatic individuals (with a history of numerous episodes of recurrent herpetic disease) and asymptomatic (ASYMP) individuals (who are infected but never experienced any recurrent herpetic disease). Frequent polyfunctional HSV-specific IFN-γ+CD107a/b+CD44highCD62LlowCD8+ effector memory T cells were detected in ASYMP individuals and were primarily directed against three "ASYMP" epitopes. In contrast, symptomatic individuals have more monofunctional CD44highCD62LhighCD8+ central memory T cells. Furthermore, therapeutic immunization with an innovative prime/pull vaccine, based on priming with multiple ASYMP epitopes (prime) and neurotropic TG delivery of the T cell-attracting chemokine CXCL10 (pull), boosted the number and function of CD44highCD62LlowCD8+ effector memory T cells and CD103highCD8+ tissue-resident T cells in TG of latently infected HLA-A*0201-transgenic mice and reduced recurrent ocular herpes following UV-B-induced reactivation. These findings have profound implications in the development of T cell-based immunotherapeutic strategies to treat blinding recurrent herpes infection and disease.


Asunto(s)
Linfocitos T CD8-positivos/inmunología , Herpesvirus Humano 1/inmunología , Memoria Inmunológica , Queratitis Herpética/inmunología , Ganglio del Trigémino/inmunología , Ganglio del Trigémino/virología , Latencia del Virus , Adulto , Anciano , Animales , Linfocitos T CD8-positivos/fisiología , Quimiocina CXCL10/inmunología , Epítopos/química , Epítopos/inmunología , Epítopos/aislamiento & purificación , Epítopos de Linfocito T/inmunología , Femenino , Humanos , Inmunización , Queratitis Herpética/terapia , Queratitis Herpética/virología , Masculino , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Recurrencia , Ganglio del Trigémino/citología , Adulto Joven
13.
BMC Med Res Methodol ; 17(1): 75, 2017 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-28446127

RESUMEN

BACKGROUND: We describe a novel strategy for power and sample size determination developed for studies utilizing investigational technologies with limited available preliminary data, specifically of imaging biomarkers. We evaluated diffuse optical spectroscopic imaging (DOSI), an experimental noninvasive imaging technique that may be capable of assessing changes in mammographic density. Because there is significant evidence that tamoxifen treatment is more effective at reducing breast cancer risk when accompanied by a reduction of breast density, we designed a study to assess the changes from baseline in DOSI imaging biomarkers that may reflect fluctuations in breast density in premenopausal women receiving tamoxifen. METHOD: While preliminary data demonstrate that DOSI is sensitive to mammographic density in women about to receive neoadjuvant chemotherapy for breast cancer, there is no information on DOSI in tamoxifen treatment. Since the relationship between magnetic resonance imaging (MRI) and DOSI has been established in previous studies, we developed a statistical simulation approach utilizing information from an investigation of MRI assessment of breast density in 16 women before and after treatment with tamoxifen to estimate the changes in DOSI biomarkers due to tamoxifen. RESULTS: Three sets of 10,000 pairs of MRI breast density data with correlation coefficients of 0.5, 0.8 and 0.9 were simulated and generated and were used to simulate and generate a corresponding 5,000,000 pairs of DOSI values representing water, ctHHB, and lipid. Minimum sample sizes needed per group for specified clinically-relevant effect sizes were obtained. CONCLUSION: The simulation techniques we describe can be applied in studies of other experimental technologies to obtain the important preliminary data to inform the power and sample size calculations.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Densidad de la Mama/efectos de los fármacos , Neoplasias de la Mama/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Mamografía/métodos , Imagen Óptica/métodos , Tamoxifeno/uso terapéutico , Biomarcadores/análisis , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/tratamiento farmacológico , Simulación por Computador , Femenino , Humanos , Tamaño de la Muestra
14.
AJR Am J Roentgenol ; 208(4): 933-939, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28199152

RESUMEN

OBJECTIVE: We hypothesize that radiologists' estimated percentage likelihood assessments for the presence of ductal carcinoma in situ (DCIS) and invasive cancer may predict histologic outcomes. MATERIALS AND METHODS: Two hundred fifty cases categorized as BI-RADS category 4 or 5 at four University of California Medical Centers were retrospectively reviewed by 10 academic radiologists with a range of 1-39 years in practice. Readers assigned BI-RADS category (1, 2, 3, 4a, 4b, 4c, or 5), estimated percentage likelihood of DCIS or invasive cancer (0-100%), and confidence rating (1 = low, 5 = high) after reviewing screening and diagnostic mammograms and ultrasound images. ROC curves were generated. RESULTS: Sixty-two percent (156/250) of lesions were benign and 38% (94/250) were malignant. There were 26 (10%) DCIS, 20 (8%) invasive cancers, and 48 (19%) cases of DCIS and invasive cancer. AUC values were 0.830-0.907 for invasive cancer and 0.731-0.837 for DCIS alone. Sensitivity of 82% (56/68), specificity of 84% (153/182), positive predictive value (PPV) of 66% (56/85), negative predictive value (NPV) of 93% (153/165), and accuracy of 84% ([56 + 153]/250) were calculated using an estimated percentage likelihood of 20% or higher as the prediction threshold for invasive cancer for the radiologist with the highest AUC (0.907; 95% CI, 0.864-0.951). Every 20% increase in the estimated percentage likelihood of invasive cancer increased the odds of invasive cancer by approximately two times (odds ratio, 2.4). For DCIS, using a threshold of 40% or higher, sensitivity of 81% (21/26), specificity of 79% (178/224), PPV of 31% (21/67), NPV of 97% (178/183), and accuracy of 80% ([21 + 178]/250) were calculated. Similarly, these values were calculated at thresholds of 2% or higher (BI-RADS category 4) and 95% or higher (BI-RADS category 5) to predict the presence of malignancy. CONCLUSION: Using likelihood estimates, radiologists may predict the presence of invasive cancer with fairly high accuracy. Radiologist-assigned estimated percentage likelihood can predict the presence of DCIS, albeit with lower accuracy than that for invasive cancer.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Carcinoma Ductal de Mama/diagnóstico por imagen , Carcinoma Ductal de Mama/patología , Competencia Clínica/estadística & datos numéricos , Radiólogos/estadística & datos numéricos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/epidemiología , California/epidemiología , Femenino , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Variaciones Dependientes del Observador , Prevalencia , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
16.
J Gastroenterol Hepatol ; 32(4): 797-802, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27784128

RESUMEN

BACKGROUND AND AIM: Women who are homozygous for the p.C282Y mutation in the HFE gene are at much lower risk of iron overload-related disease than p.C282Y homozygous men, presumably because of the iron-depleting effects of menstruation and pregnancy. We used data from a population cohort study to model the impact of menstruation cessation at menopause on serum ferritin (SF) levels in female p.C282Y homozygotes, with p.C282Y/p.H63D simple or compound heterozygotes and those with neither p.C282Y nor p.H63D mutations (HFE wild types) as comparison groups. METHODS: A sample of the Melbourne Collaborative Cohort Study was selected for the "HealthIron" study (n = 1438) including all HFE p.C282Y homozygotes plus a random sample stratified by HFE-genotype (p.C282Y and p.H63D). The relationship between the natural logarithm of SF and time since menopause was examined using linear mixed models incorporating spline smoothing. RESULTS: For p.C282Y homozygotes, SF increased by a factor of 3.6 (95% CI (1.8, 7.0), P < 0.001) during the first 10 years postmenopause, after which SF continued to increase but at less than half the previous rate. In contrast, SF profiles for other HFE genotype groups increase more gradually and did not show a distinction between premenopausal and postmenopausal SF levels. Only p.C282Y homozygotes had predicted SF exceeding 200 µg/L postmenopause, but the projected SF did not increase the risk of iron overload-related disease. CONCLUSIONS: These data provide the first documented evidence that physiological blood loss is a major factor in determining the marked gender difference in expression of p.C282Y homozygosity.


Asunto(s)
Ferritinas/sangre , Predisposición Genética a la Enfermedad/genética , Genotipo , Proteína de la Hemocromatosis/genética , Hemocromatosis/genética , Homocigoto , Menopausia/sangre , Menopausia/genética , Mutación/genética , Adulto , Anciano , Australia , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad
17.
Gastrointest Endosc ; 85(5): 996-1001, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27693644

RESUMEN

BACKGROUND AND AIMS: Portal hypertension (PH) is a serious adverse event of liver cirrhosis. The hepatic venous pressure gradient or portal pressure gradient (PPG) accurately reflects the degree of PH and is the single best prognostic indicator in liver disease. This is usually obtained by interventional radiology (IR), although it is not routinely performed. Recently, we developed a simple novel technique for EUS-guided PPG measurement (PPGM). Our animal studies showed excellent correlation between EUS-PPGM and IR-PPGM. We present the first human pilot study of EUS-PPGM in patients with liver disease. METHODS: EUS-PPGM was performed by experienced endosonographers using a linear echoendoscope, a 25-gauge fine-needle aspiration needle, and a novel compact manometer. The portal vein and hepatic vein (or inferior vena cava) were targeted using a transgastric-transduodenal approach. Clinical parameters of PH were evaluated in each patient. Feasibility was defined as successful PPGM in each patient. Safety was based on adverse events captured in a postprocedural interview. RESULTS: Twenty-eight patients underwent EUS-PPGM with 100% technical success and no adverse events. PPG ranged from 1.5 to 19 mm Hg and had excellent correlation with clinical parameters of portal hypertension including the presence of varices (P = .0002), PH gastropathy (P = .007), and thrombocytopenia (P = .036). PPG was increased in patients with high clinical evidence of cirrhosis (P = .005). CONCLUSION: This novel technique of EUS-PPGM using a 25-gauge needle and compact manometer is feasible and appears safe. Given the availability of EUS and the simplicity of the manometry setup, EUS-guided PPG may represent a promising breakthrough for procuring indispensable information in the management of patients with liver disease.


Asunto(s)
Determinación de la Presión Sanguínea/métodos , Endosonografía/métodos , Hipertensión Portal/diagnóstico , Presión Portal , Adulto , Anciano , Anciano de 80 o más Años , Várices Esofágicas y Gástricas/etiología , Estudios de Factibilidad , Femenino , Venas Hepáticas , Humanos , Hipertensión Portal/complicaciones , Cirrosis Hepática/complicaciones , Masculino , Manometría/instrumentación , Persona de Mediana Edad , Agujas , Proyectos Piloto , Vena Porta , Gastropatías/etiología , Trombocitopenia/etiología , Vena Cava Inferior
18.
Blood Cells Mol Dis ; 63: 15-20, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27936396

RESUMEN

BACKGROUND: GNPAT p.D519G positivity is significantly increased in HFE p.C282Y homozygotes with markedly increased iron stores. We sought to determine associations of p.D519G and iron-related variables with iron stores in p.C282Y homozygotes. METHODS: We defined markedly increased iron stores as serum ferritin >2247pmol/L (>1000µg/L) and either hepatic iron >236µmol/g dry weight or iron >10g by induction phlebotomy (men and women). We defined normal or mildly elevated iron stores as serum ferritin <674.1pmol/L (<300µg/L) or either age≥40y with iron ≤2.5g iron by induction phlebotomy or age≥50y with ≤3.0g iron by induction phlebotomy (men only). We compared participant subgroups using univariate methods. Using multivariable logistic regression, we evaluated associations of markedly increased iron stores with these variables: age; iron supplement use (dichotomous); whole blood units donated; erythrocyte units received as transfusion; daily alcohol consumption, g; and p.D519G positivity (heterozygosity or homozygosity). RESULTS: The mean age of 56 participants (94.6% men) was 55±10 (SD) y; 41 had markedly increased iron stores. Prevalences of swollen/tender 2nd/3rd metacarpophalangeal joints and elevated aspartate or alanine aminotransferase were significantly greater in participants with markedly increased iron stores. Only participants with markedly increased iron stores had cirrhosis. In multivariable analyses, p.D519G positivity was the only exposure variable significantly associated with markedly increased iron stores (odds ratio 9.9, 95% CI [1.6, 60.3], p=0.0126). CONCLUSIONS: GNPAT p.D519G is strongly associated with markedly increased iron stores in p.C282Y homozygotes after correction for age, iron-related variables, and alcohol consumption.


Asunto(s)
Aciltransferasas/genética , Proteína de la Hemocromatosis/genética , Hierro/metabolismo , Mutación Missense , Aciltransferasas/metabolismo , Adulto , Factores de Edad , Anciano , Consumo de Bebidas Alcohólicas , Femenino , Proteína de la Hemocromatosis/metabolismo , Homocigoto , Humanos , Masculino , Persona de Mediana Edad
19.
PLoS One ; 11(9): e0163322, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27661980

RESUMEN

Both familial and sporadic porphyria cutanea tarda (PCT) are iron dependent diseases. Symptoms of PCT resolve when iron stores are depleted by phlebotomy, and a sequence variant of HFE (C282Y, c.843G>A, rs1800562) that enhances iron aborption by reducing hepcidin expression is a risk factor for PCT. Recently, a polymorphic variant (D519G, c.1556A>G, rs11558492) of glyceronephosphate O-acyltransferase (GNPAT) was shown to be enriched in male patients with type I hereditary hemochromatosis (HFE C282Y homozygotes) who presented with a high iron phenotype, suggesting that GNPAT D519G, like HFE C282Y, is a modifier of iron homeostasis that favors iron absorption. To challenge this hypothesis, we investigated the frequency of GNPAT D519G in patients with both familial and sporadic PCT. Patients were screened for GNPAT D519G and allelic variants of HFE (both C282Y and H63D). Nucleotide sequencing of uroporphyrinogen decarboxylase (URO-D) identified mutant alleles. Patients with low erythrocyte URO-D activity or a damaging URO-D variant were classified as familial PCT (fPCT) and those with wild-type URO-D were classified as sporadic PCT (sPCT). GNPAT D519G was significantly enriched in the fPCT patient population (p = 0.0014) but not in the sPCT population (p = 0.4477). Both HFE C282Y and H63D (c.187C>G, rs1799945) were enriched in both PCT patient populations (p<0.0001) but showed no greater association with fPCT than with sPCT. CONCLUSION: GNPAT D519G is a risk factor for fPCT, but not for sPCT.

20.
J Biomed Opt ; 21(7): 74001, 2016 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-27436049

RESUMEN

Young patients with dense breasts have a relatively low-positive biopsy rate for breast cancer (∼1 in 7). South Korean women have higher breast density than Westerners. We investigated the benefit of using a functional and metabolic imaging technique, diffuse optical spectroscopic imaging (DOSI), to help the standard of care imaging tools to distinguish benign from malignant lesions in premenopausal Korean women. DOSI uses near-infrared light to measure breast tissue composition by quantifying tissue concentrations of water (ctH2O), bulk lipid (ctLipid), deoxygenated (ctHHb), and oxygenated (ctHbO2) hemoglobin. DOSI spectral signatures specific to abnormal tissue and absent in healthy tissue were also used to form a malignancy index. This study included 19 premenopausal subjects (average age 41±9), corresponding to 11 benign and 10 malignant lesions. Elevated lesion to normal ratio of ctH2O, ctHHb, ctHbO2, total hemoglobin (THb=ctHHb+ctHbO2), and tissue optical index (ctHHb×ctH2O/ctLipid) were observed in the malignant lesions compared to the benign lesions (p<0.02). THb and malignancy index were the two best single predictors of malignancy, with >90% sensitivity and specificity. Malignant lesions showed significantly higher metabolism and perfusion than benign lesions. DOSI spectral features showed high discriminatory power for distinguishing malignant and benign lesions in dense breasts of the Korean population.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Mama/diagnóstico por imagen , Imagen Óptica/instrumentación , Adulto , Diagnóstico Diferencial , Femenino , Humanos , Persona de Mediana Edad , República de Corea , Sensibilidad y Especificidad , Espectroscopía Infrarroja Corta
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