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1.
J Endocrinol Invest ; 45(9): 1683-1688, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35606667

RESUMEN

OBJECTIVE: To assess the impact of baseline body mass index (BMI) on the outcomes of patients with neuroendocrine neoplasms (NENs) in a population-based setting. METHODS: Linked provincial administrative databases (within the province of Alberta, Canada), 2004-2019, were accessed, and patients with NENs and complete information about BMI near the time of diagnosis were reviewed. The impact of BMI on overall survival was evaluated through the use of Kaplan-Meier survival estimates and multivariable Cox regression modeling. RESULTS: A total of 1010 patients with NENs and BMI information were included. Using Kaplan-Meier survival estimates, survival outcomes were best with individuals with obesity and were worst with underweight individuals (P < 0.0001). The following factors were associated with worse overall survival, older age (HR: 1.02; 95% CI: 1.01-1.03), male sex (HR: 1.60; 95% CI: 1.32-1.93), higher Charlson comorbidity index (HR: 1.22; 95% CI: 1.13-1.31), non-small intestinal primary (HR for gastric primary versus small intestinal primary: 2.36; 95% CI: 1.44-3.85), stage 4 disease (HR: 2.67; 95% CI: 2.16-3.31), neuroendocrine carcinoma histology (HR: 1.76; 95% CI: 1.43-2.17), and underweight BMI (HR versus normal BMI: 1.74; 95% CI: 1.11-2.73). When the model was repeated using BMI as a continuous variable (rather than as a categorical variable), increasing BMI was associated with better overall survival (HR with increasing BMI: 0.97; 95% CI: 0.95-0.98). CONCLUSIONS: Lower BMI is associated with worse overall survival among patients with NENs. This finding was demonstrable regardless of the tumor's stage or histology.


Asunto(s)
Tumores Neuroendocrinos , Delgadez , Índice de Masa Corporal , Humanos , Estimación de Kaplan-Meier , Masculino , Tumores Neuroendocrinos/patología , Obesidad/complicaciones , Obesidad/diagnóstico , Obesidad/epidemiología , Pronóstico , Estudios Retrospectivos , Delgadez/diagnóstico , Delgadez/epidemiología
2.
Osteoporos Int ; 23(2): 573-80, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21380637

RESUMEN

SUMMARY: Bisphosphonate treatment rates were examined before and after admission to long-term residential care. Bisphosphonate treatment rates were low (16%) pre-admission but doubled after long-term residential care admission (30%). Men were very undertreated for osteoporosis, while a history of falls with injury was not associated with treatment. INTRODUCTION: To determine the rates and independent correlates of bisphosphonate treatment in elderly residents before and after admission to long-term care (LTC) institutions. METHODS: Information was collected from records of 421 residents of four LTC institutions in Edmonton, Alberta, Canada. Osteoporosis-related diagnoses, treatments, and risk factors including falls in LTC and any adulthood fractures were abstracted. Osteoporosis was defined by physician diagnosis or documented fractures of the hip, spine, or upper extremity. Multivariable analyses were undertaken to determine factors independently associated with bisphosphonate treatment. RESULTS: Mean age was 84 ± 8 years and 290 (70%) were female. Overall, 142 (34%) had previous fractures, 170 (41%) had physician-diagnosed osteoporosis, and 227 (54%) residents met the study's clinical definition of osteoporosis. Of those with osteoporosis, 44 (19%) were men. Before admission, 36 (16%) patients with osteoporosis were treated with bisphosphonates; after admission another 31 (14%) were started on bisphosphonates by LTC physicians. Women were far more likely than men to start bisphosphonate treatment [30 (97%) women vs. 1 (3%) man, adjusted odds ratio (aOR) = 9.20 (95% confidence intervals 1.2,70.5)]. Falls with injury were common [72/227 (31%)] but not associated with bisphosphonate treatment (adjusted p value > 0.5). CONCLUSION: Rates of pre-admission bisphosphonate treatment were low, but did double after LTC admission. Women were almost ten times more likely to start bisphosphonate treatment than men, although one fifth of those with documented osteoporosis were men. Although falls cause most fractures, a history of falls with injury was not associated with bisphosphonate treatment. Our findings suggest that targeting men and residents with falls for treatment with bisphosphonates might be warranted.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Hogares para Ancianos , Institucionalización , Osteoporosis/diagnóstico , Osteoporosis/tratamiento farmacológico , Accidentes por Caídas , Anciano , Anciano de 80 o más Años , Alberta , Difosfonatos/uso terapéutico , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Humanos , Cuidados a Largo Plazo , Masculino , Osteoporosis Posmenopáusica/diagnóstico , Osteoporosis Posmenopáusica/tratamiento farmacológico , Fracturas Osteoporóticas/etiología , Fracturas Osteoporóticas/prevención & control , Estudios Retrospectivos , Factores Sexuales
3.
Osteoporos Int ; 22(6): 1799-808, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20878389

RESUMEN

UNLABELLED: In a randomized trial, a multifaceted intervention tripled rates of osteoporosis treatment in older patients with wrist fracture. An economic analysis of the trial now demonstrates that the intervention tested "dominates" usual care: over a lifetime horizon, it reduces fracture, increases quality-adjusted life years, and saves the healthcare system money. INTRODUCTION: In a randomized trial (N = 272), we reported a multifaceted quality improvement intervention directed at older patients and their physicians could triple rates of osteoporosis treatment within 6 months of a wrist fracture when compared with usual care (22% vs 7%). Alongside the trial, we conducted an economic evaluation. METHODS: Using 1-year outcome data from our trial and micro-costing time-motion studies, we constructed a Markov decision-analytic model to determine cost-effectiveness of the intervention compared with usual care over the patients' remaining lifetime. We took the perspective of third-party healthcare payers. In the base case, costs and benefits were discounted at 3% and expressed in 2006 Canadian dollars. One-way deterministic and probabilistic sensitivity analyses were conducted. RESULTS: Median age of patients was 60 years, 77% were women, and 72% had low bone mineral density (BMD). The intervention cost $12 per patient. Compared with usual care, the intervention strategy was dominant: for every 100 patients receiving the intervention, three fractures (one hip fracture) would be prevented, 1.1 quality-adjusted life year gained, and $26,800 saved by the healthcare system over their remaining lifetime. The intervention dominated usual care across numerous one-way sensitivity analyses: with respect to cost, the most influential parameter was drug price; in terms of effectiveness, the most influential parameter was rate of BMD testing. The intervention was cost saving in 80% of probabilistic model simulations. CONCLUSIONS: For outpatients with wrist fractures, our multifaceted osteoporosis intervention was cost-effective. Healthcare systems implementing similar interventions should expect to save money, reduce fractures, and gain quality-adjusted life expectancy.


Asunto(s)
Osteoporosis/terapia , Fracturas Osteoporóticas/prevención & control , Mejoramiento de la Calidad/economía , Traumatismos de la Muñeca/etiología , Anciano , Alberta , Densidad Ósea/fisiología , Análisis Costo-Beneficio , Técnicas de Apoyo para la Decisión , Métodos Epidemiológicos , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Modelos Econométricos , Osteoporosis/complicaciones , Osteoporosis/economía , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/economía , Fracturas Osteoporóticas/fisiopatología , Mejoramiento de la Calidad/organización & administración , Años de Vida Ajustados por Calidad de Vida , Prevención Secundaria , Traumatismos de la Muñeca/fisiopatología
4.
Osteoporos Int ; 22(1): 223-30, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20358359

RESUMEN

UNLABELLED: Few outpatients with fractures are treated for osteoporosis in the years following fracture. In a randomized pilot study, we found a nurse case-manager could double rates of osteoporosis testing and treatment compared with a proven efficacious quality improvement strategy directed at patients and physicians (57% vs 28% rates of appropriate care). INTRODUCTION: Few patients with fractures are treated for osteoporosis. An intervention directed at wrist fracture patients (education) and physicians (guidelines, reminders) tripled osteoporosis treatment rates compared to controls (22% vs 7% within 6 months of fracture). More effective strategies are needed. METHODS: We undertook a pilot study that compared a nurse case-manager to the multifaceted intervention using a randomized trial design. The case-manager counseled patients, arranged bone mineral density (BMD) tests, and prescribed treatments. We included controls from our first trial who remained untreated for osteoporosis 1-year post-fracture. Primary outcome was bisphosphonate treatment and secondary outcomes were BMD testing, appropriate care (BMD test-treatment if bone mass low), and costs. RESULTS: Forty six patients untreated 1-year after wrist fracture were randomized to case-manager (n = 21) or multifaceted intervention (n = 25). Median age was 60 years and 68% were female. Six months post-randomization, 9 (43%) case-managed patients were treated with bisphosphonates compared with 3 (12%) multifaceted intervention patients (relative risk [RR] 3.6, 95% confidence intervals [CI] 1.1-11.5, p = 0.019). Case-managed patients were more likely than multifaceted intervention patients to undergo BMD tests (81% vs 52%, RR 1.6, 95%CI 1.1-2.4, p = 0.042) and receive appropriate care (57% vs 28%, RR 2.0, 95%CI 1.0-4.2, p = 0.048). Case-management cost was $44 (CDN) per patient vs $12 for the multifaceted intervention. CONCLUSIONS: A nurse case-manager substantially increased rates of appropriate testing and treatment for osteoporosis in patients at high-risk of future fracture when compared with a multifaceted quality improvement intervention aimed at patients and physicians. Even with case-management, nearly half of patients did not receive appropriate care. TRIAL REGISTRY: clinicaltrials.gov identifier: NCT00152321.


Asunto(s)
Enfermeras Administradoras , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/diagnóstico , Mejoramiento de la Calidad , Traumatismos de la Muñeca/etiología , Anciano , Alberta , Densidad Ósea , Conservadores de la Densidad Ósea/uso terapéutico , Atención a la Salud/economía , Atención a la Salud/métodos , Atención a la Salud/normas , Difosfonatos/uso terapéutico , Métodos Epidemiológicos , Femenino , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Enfermeras Administradoras/economía , Osteoporosis/diagnóstico , Osteoporosis/economía , Osteoporosis/fisiopatología , Fracturas Osteoporóticas/economía , Fracturas Osteoporóticas/fisiopatología , Traumatismos de la Muñeca/economía , Traumatismos de la Muñeca/fisiopatología
5.
Osteoporos Int ; 22(3): 983-91, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21052642

RESUMEN

UNLABELLED: Intravenous bisphosphonates reduce mortality following hip fracture. We determined whether new use of oral bisphosphonates was also associated with reductions in mortality in 209 hip fracture patients. Oral bisphosphonate exposure led to relative reduction of 8% per month of use (p = 0.001) or about a 60% reduction in mortality per year of use. INTRODUCTION: Intravenous bisphosphonates reduce mortality following hip fracture. Using prospectively collected long-term data from a randomized trial of osteoporosis quality improvement for hip fracture, we determined whether new use of oral bisphosphonates was associated with reductions in mortality or the composite outcome of death or new fracture. METHODS: Originally, 220 hip fracture patients were randomized to case manager (n = 110) or usual care followed by facilitated bone mineral density (BMD) testing (n = 110) interventions. All were eligible for bisphosphonate treatment. Post-randomization, we followed patients for 3 years and ascertained bisphosphonate treatment, medication adherence and persistence, all-cause mortality, and new clinical fractures. Proportional hazards analyses with time-varying treatment status were undertaken. RESULTS: The final study cohort included 209 patients: 136 (65%) females, 104 (50%) older than 75 years, 90 (43%) with poor self-reported health, and 38 (18%) underweight. Of these, 76 (36%) had a previous fracture before hip fracture and 132 (81%) had low BMD. A total of 101 (46%) patients started oral bisphosphonates and 65 (64%) remained on treatment at the final evaluation. Overall, 24 (11%) patients died, 19 (9%) had new fractures, and 42 (20%) reached the composite outcome of death or fracture. Compared to no treatment, bisphosphonate exposure was independently associated with reduced mortality (17[16%] vs. 7[7%]; adjusted hazard ratio (aHR) = 0.92 per month treated; 95%CI, 0.88-0.97) and composite endpoints (28[26%] vs. 5[15%]; aHR = 0.94 per month treated; 95%CI, 0.91-0.97). CONCLUSION: Like intravenous bisphosphonates after hip fracture, our study suggests that oral bisphosphonates may be associated with reductions in all-cause mortality.


Asunto(s)
Conservadores de la Densidad Ósea/administración & dosificación , Difosfonatos/administración & dosificación , Fracturas de Cadera/mortalidad , Osteoporosis/tratamiento farmacológico , Fracturas Osteoporóticas/mortalidad , Administración Oral , Anciano , Femenino , Humanos , Masculino , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto
7.
Osteoporos Int ; 18(3): 261-70, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17086470

RESUMEN

INTRODUCTION: Older patients with fragility fractures are not commonly tested or treated for osteoporosis. Compared to usual care, a previously reported intervention led to 30% absolute increases in osteoporosis treatment within 6 months of wrist fracture. Our objective was to examine longer-term outcomes, reproducibility, and cost-effectiveness of this intervention. METHODS: We conducted an extended analysis of a non-randomized controlled trial with blinded ascertainment of outcomes that compared a multifaceted intervention to usual care controls. Patients >50 years with a wrist fracture treated in two Emergency Departments in the province of Alberta, Canada were included; those already treated for osteoporosis were excluded. Overall, 102 patients participated in this study (55 intervention and 47 controls; median age: 66 years; 78% were women). The interventions consisted of faxed physician reminders that contained osteoporosis treatment guidelines endorsed by opinion leaders and patient counseling. Controls received usual care; at 6-months post-fracture, when the original trial was completed, all controls were crossed-over to intervention. The main outcomes were rates of osteoporosis testing and treatment within 6 months (original study) and 1 year (delayed intervention) of fracture, and 1-year persistence with treatments started. From the perspective of the healthcare payer, the cost-effectiveness (using a Markov decision-analytic model) of the intervention was compared with usual care over a lifetime horizon. RESULTS: Overall, 40% of the intervention patients (vs. 10% of the controls) started treatment within 6 months post-fracture, and 82% (95%CI: 67-96%) had persisted with it at 1-year post-fracture. Delaying the intervention to controls for 6 months still led to equivalent rates of bone mineral density (BMD) testing (64 vs. 60% in the original study; p = 0.72) and osteoporosis treatment (43 vs. 40%; p = 0.77) as previously reported. Compared with usual care, the intervention strategy was dominant - per patient, it led to a $13 Canadian (U.S. $9) cost savings and a gain of 0.012 quality-adjusted life years. Base-case results were most sensitive to assumptions about treatment cost; for example, a 50% increase in the price of osteoporosis medication led to an incremental cost-effectiveness ratio of $24,250 Canadian (U.S. $17,218) per quality-adjusted life year gained. CONCLUSIONS: A pragmatic intervention directed at patients and physicians led to substantial improvements in osteoporosis treatment, even when delivered 6-months post-fracture. From the healthcare payer's perspective, the intervention appears to have led to both cost-savings and gains in life expectancy.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Fracturas Óseas/etiología , Osteoporosis/complicaciones , Calidad de la Atención de Salud , Traumatismos de la Muñeca/etiología , Anciano , Anciano de 80 o más Años , Alberta , Conservadores de la Densidad Ósea/economía , Análisis Costo-Beneficio , Métodos Epidemiológicos , Femenino , Fracturas Óseas/economía , Fracturas Óseas/prevención & control , Costos de la Atención en Salud/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Osteoporosis/tratamiento farmacológico , Osteoporosis/economía , Osteoporosis Posmenopáusica/complicaciones , Osteoporosis Posmenopáusica/tratamiento farmacológico , Osteoporosis Posmenopáusica/economía , Cooperación del Paciente/estadística & datos numéricos , Calidad de Vida , Resultado del Tratamiento , Traumatismos de la Muñeca/economía
8.
Mol Hum Reprod ; 12(7): 427-33, 2006 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16709596

RESUMEN

Elevated circulating levels of the tachykinin, neurokinin B (NKB), have been observed in women with pre-eclampsia during the third trimester of pregnancy. Currently, the molecular mechanisms responsible for these increased levels remain unknown. To understand the molecular regulation, we have compared the differences in gene expression of the tachykinins and their receptors in control and pre-eclamptic placentae and the responses of the TAC3 gene encoding NKB to proposed physiological triggers of pre-eclampsia including hypoxia and oxidative stress using real-time quantitative PCR. We have determined the placenta to be the main site of TAC3 expression with levels 2.6-fold higher than the brain. TAC3 expression was found to be significantly higher in pre-eclamptic placenta (1.7-fold, P < 0.05) than in normal controls. No evidence was found that hypoxia and oxidative stress were responsible for increases in TAC3 expression. In rat placenta, a longitudinal study in normal late pregnancy was associated with a significant down-regulation of the NKB/NK3 ligand-receptor pair (P < 0.05). The present data suggest that the increased placental expression of TAC3 is part of the mechanism leading to the increased circulating levels of NKB in pre-eclampsia.


Asunto(s)
Regulación de la Expresión Génica/genética , Neuroquinina B/genética , Preeclampsia/genética , Receptores de Neuroquinina-3/genética , Animales , Células Cultivadas , Femenino , Humanos , Hipoxia/fisiopatología , Masculino , Placenta/metabolismo , Preeclampsia/metabolismo , Preeclampsia/patología , Embarazo , Trimestres del Embarazo , Ratas , Receptores de Taquicininas/genética , Taquicininas/genética , Trofoblastos/citología , Trofoblastos/metabolismo
9.
Placenta ; 27 Suppl A: S141-3, 2006 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16542721

RESUMEN

Challenge lies ahead in unravelling the role played by trophoblast and its repertoire of expressed genes in normal human placental development, growth and pathology. Specific technical advances will clearly be required for characterisation of function. In particular, improvements in our repertoire of in vitro models are needed before many of the key questions can be answered. Recent advances in the study of human trophoblast differentiation are discussed.


Asunto(s)
Comunicación Celular , Diferenciación Celular , Regulación del Desarrollo de la Expresión Génica , Células Madre/fisiología , Trofoblastos/fisiología , Fusión Celular , Linaje de la Célula , Movimiento Celular , Humanos
10.
Clin Genet ; 66(4): 349-52, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15355438

RESUMEN

One of the major goals of genetic testing is the reduction of morbidity and mortality. Given the appropriate circumstances, this can result in reduction in health care costs. Such savings can be demonstrated most effectively in large families with mutations in well characterized, dominantly acting genes. In our large family, a point mutation TGC>CGC in exon 10 of the RET proto-oncogene, which results in a missense mutation (Cys620Arg), was identified in two individuals. The proband has medullary thyroid carcinoma (MTC), as did her deceased mother. One son has MTC and Hirschsprung's disease. The proband's mother had nine siblings; the proband has three siblings, another son, and 69 maternal cousins. Genetic testing has been performed on the closest relatives and has identified four individuals with, and 54 individuals without, a familial RET mutation. Significant cost savings have been realized in both genetic testing and clinical surveillance. In this family, for every at-risk individual identified as a true-negative, the minimum yearly savings in clinical surveillance is 508 dollars per person. As demonstrated by this case, economic costs of genetic diagnostics should take into account the potential saved monies in tests, both molecular and clinical.


Asunto(s)
Carcinoma Medular/genética , Pruebas Genéticas/economía , Neoplasia Endocrina Múltiple Tipo 2a/economía , Neoplasia Endocrina Múltiple Tipo 2a/genética , Neoplasia Endocrina Múltiple Tipo 2b/economía , Neoplasia Endocrina Múltiple Tipo 2b/genética , Proteínas Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/genética , Canadá/epidemiología , Costos y Análisis de Costo , ADN/análisis , Análisis Mutacional de ADN , Familia , Femenino , Mutación de Línea Germinal/genética , Enfermedad de Hirschsprung/genética , Humanos , Masculino , Neoplasia Endocrina Múltiple Tipo 2a/cirugía , Neoplasia Endocrina Múltiple Tipo 2b/cirugía , Linaje , Proto-Oncogenes Mas , Proteínas Proto-Oncogénicas c-ret , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Tiroidectomía
12.
Placenta ; 23(2-3): 175-83, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-11945084

RESUMEN

Recent studies suggest that purified villous cytotrophoblasts are largely contaminated by mononucleated syncytial fragments and therefore unsuitable for studies of trophoblast differentiation. We assessed highly purified (>99.99 per cent) populations of villous trophoblasts for fragment contamination using the syncytial markers placental alkaline phosphatase (PLAP, by immunohistochemistry) and exteriorized phosphatidyl serine (ePS, by flow cytometric analysis). The preparations contained from 4-46 per cent syncytial fragments. However, we find that PLAP negative cells preferentially adhere to tissue culture surfaces and that all preparations were <2 per cent PLAP positive after routine plating and washing procedures. A second purification procedure eliminated dead (propidium iodide permeable) cells and separated viable syncytial fragments (ePS-positive) from viable cytotrophoblasts (ePS-negative) by two colour fluorescence activated cell sorting (FACS). Viable ePS-positive cells were ultrastructurally apoptotic, adhered poorly in culture and those that adhered rapidly underwent apoptosis. Viable ePS-negative cells contained large heterochromic nuclei and cytoplasmic structures, adhered strongly in culture and remained viable. The latter population (putative true villous CT) differentiated into syncytialized cells when cultured with EGF. We conclude that villous CT can be routinely purified, are viable in culture and can undergo syncytial fusion without extensive preformed syncytium.


Asunto(s)
Separación Celular/métodos , Vellosidades Coriónicas/anatomía & histología , Células Gigantes/citología , Trofoblastos/citología , Adulto , Fosfatasa Alcalina , Adhesión Celular , Fusión Celular , Supervivencia Celular , Células Cultivadas , Vellosidades Coriónicas/metabolismo , Fragmentación del ADN , Femenino , Citometría de Flujo , Técnica del Anticuerpo Fluorescente Indirecta , Proteínas Ligadas a GPI , Células Gigantes/metabolismo , Humanos , Etiquetado Corte-Fin in Situ , Isoenzimas/metabolismo , Fosfatidilserinas/metabolismo , Placenta/enzimología , Embarazo , Trofoblastos/metabolismo
13.
Am J Surg ; 182(2): 185-7, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11574094

RESUMEN

The occurrence of multiple endocrine tumors is rare; however, they may be found with hereditary diseases such as multiple endocrine neoplasia (MEN). The endocrine tumors involved with these diseases are well documented. We present a case of a patient with a pheochromocytoma and a growth hormone (GH) secreting pituitary adenoma. This association is not described with any of the known MEN syndromes. The association may be a cross-over MEN syndrome or a secondarily induced GH-secreting pituitary adenoma from a pheochromocytoma producing growth hormone releasing hormone (GHRH) instead of catecholamines.


Asunto(s)
Acromegalia/etiología , Neoplasias de las Glándulas Suprarrenales/complicaciones , Neoplasia Endocrina Múltiple/complicaciones , Neoplasias Primarias Múltiples/complicaciones , Feocromocitoma/complicaciones , Adulto , Humanos , Masculino
15.
Hypertension ; 37(2): 227-31, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11230276

RESUMEN

Adrenomedullin is a potent vasodilatory peptide with plasma levels that increase during pregnancy. Although fetoplacental adrenomedullin levels are reported to increase in preeclampsia, maternal plasma levels may be elevated or decreased, or they may resemble those in normal pregnancy. In other hypertensive conditions, adrenomedullin increases. Therefore, we hypothesized that maternal plasma adrenomedullin levels would be higher in hypertensive pregnancies than in normotensive pregnancies and that the higher placental resistance found in preeclamptic pregnancies results from blunted activity of adrenomedullin on the vasculature. Adrenomedullin concentrations in plasma from women with normotensive pregnancies, gestational hypertension, and preeclampsia were determined by radioimmunoassay. Stem villous arteries from normotensive and preeclamptic pregnancies were dissected and mounted on a wire myograph system. Arteries were first preconstricted to 80% of their maximum constriction with U46619, a thromboxane A(2) mimetic, and exposed to cumulative doses of adrenomedullin (1x10(-)(9) to 3x10(-)(7) mol/L). Contrary to our hypothesis, there were no significant differences in maternal plasma adrenomedullin levels among patients with normal pregnancies, gestational hypertension, and preeclampsia. Adrenomedullin significantly relaxed arteries from both normal and preeclamptic placentas, but there was no significant difference between the 2 groups. During normal pregnancy, adrenomedullin may contribute to the low placental vascular resistance. This pathway appears to be intact in preeclampsia. We conclude that the increased placental vascular resistance observed in preeclampsia is due neither to reduced adrenomedullin secretion nor to an attenuated vascular responsiveness. Moreover, unlike other hypertensive disorders, there is no compensatory rise in circulating adrenomedullin levels.


Asunto(s)
Arterias/efectos de los fármacos , Péptidos/farmacología , Preeclampsia/fisiopatología , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacología , Adrenomedulina , Adulto , Arterias/fisiología , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Técnicas In Vitro , Péptidos/sangre , Placenta/irrigación sanguínea , Cloruro de Potasio/farmacología , Preeclampsia/sangre , Embarazo , Vasoconstrictores/farmacología , Vasodilatación/efectos de los fármacos
16.
Curr Protein Pept Sci ; 2(3): 245-59, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12369935

RESUMEN

Differential techniques have revealed several novel genes and peptides involved in trophoblast development including PL74/gdf15/MIC-1, a TGFbeta family cytokine that controls apoptosis and differentiation, PL48, a new serine-threonine protein kinase, serum and glucocorticoid-induced kinase, PBK-1, a tunicamycin-responsive gene, a cathepsin D-like gene (DAP-1) and hypoxia- regulated genes HRF-1,2,6,8 and HIF-1alpha, HIF-1beta, and hEPAS-1. Syncytin, a cell fusion- inducing gene, has been cloned from placenta where it regulates cell fusion. ERV-3 has also been demonstrated to promote cell fusion. These two genes represent the first demonstrated functions of endogenous retroviral sequences in human tissues. Endoglin, PlGF, TGFbeta3, IGF-II, IGFBP-1, and a placental IGFBP protease have found new roles in regulating cytotrophoblast proliferation and invasiveness. A specific placental p105 rasGAP protein has been identified. The homeobox genes DLX4, HB24, MSX2 and MOX2 also likely play a role in development at the epithelial-mesenchymal boundary. Transcription factors such as TEF-5, Hand1, HEB, HASH-2 and two genes represented by ESTs may have regulatory roles in placental development. Evidence suggests that the placenta has an unusual two-cell system for apoptosis regulation in which the cytotrophoblast may direct later apoptotic events in the syncytium, and with syncytialization possibly triggered by the "phosphatidylserine flip". Thus, the placenta is both a rich source of new growth-regulatory substances, and a model system for originating new paradigms of developmental biology.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/fisiología , Placenta/fisiología , Trofoblastos/fisiología , Animales , Apoptosis/fisiología , Linaje de la Célula , Implantación del Embrión/fisiología , Células Gigantes/fisiología , Humanos , Factores de Transcripción/fisiología , Trofoblastos/citología
19.
Semin Oncol ; 27(2 Suppl 3): 11-8, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10810933

RESUMEN

Considering the single-agent activity of docetaxel (Taxotere; Rhône-Poulenc Rorer, Antony, France) and doxorubicin in breast cancer and their potential non-cross-resistance, several docetaxel/anthracycline-based combination chemotherapies were developed in phase I and II programs for metastatic breast cancer patients. The rationale for these combinations was also reinforced by the fact that docetaxel showed significant activity in phase III trials in patients previously exposed or having failed anthracycline chemotherapy. In a pivotal randomized phase III study of doxorubicin plus docetaxel versus doxorubicin plus cyclophosphamide as first-line chemotherapy for 429 patients with metastatic breast cancer, doxorubicin/docetaxel emerged as the more effective regimen. Despite a lower-dose intensity of doxorubicin, patients receiving doxorubicin/docetaxel experienced a higher response rate as well as a significantly longer time to progression and time to treatment failure. This difference was seen even in patients with poor-prognosis disease. Febrile neutropenia was more common in doxorubicin/docetaxel-treated patients. However, there were no septic deaths among 213 patients receiving doxorubicin/ docetaxel. Extrahematologic toxicity appeared mild for both regimens and the combination docetaxel/doxorubicin did not increase the cardiac toxicity expected for an anthracycline-containing regimen. Docetaxel plus doxorubicin is the first regimen, involving a newly developed agent, proven superior to a standard anthracycline-containing combination in metastatic breast cancer and its potential is now being investigated in the adjuvant setting.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Taxoides , Antibióticos Antineoplásicos/administración & dosificación , Antineoplásicos Fitogénicos/administración & dosificación , Neoplasias de la Mama/patología , Quimioterapia Adyuvante , Ensayos Clínicos como Asunto , Docetaxel , Doxorrubicina/administración & dosificación , Femenino , Humanos , Paclitaxel/administración & dosificación , Paclitaxel/análogos & derivados
20.
Placenta ; 20(5-6): 423-30, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10419807

RESUMEN

The inflammatory cytokines tumour necrosis factor alpha (TNF-alpha) and immune interferon gamma (IFN-gamma) stimulate villous cytotrophoblast apoptosis while epidermal growth factor (EGF) protects. We hypothesize that TNF-alpha, IFN-gamma and EGF regulate apoptosis in part by modulating cellular expression levels of the anti-death gene bcl-2. While Bcl-2 is reported to be strongly expressed in villous syncytiotrophoblasts, it is not known whether the protein is expressed in cultured villous cytotrophoblasts (CT) and, if so, whether it is functional. We show by Northern blot analysis that bcl-2 mRNA is expressed in cultured CT and by immunoblot analysis that the protein is strongly expressed in highly purified first trimester and term villous cytotrophoblasts. The expression levels of Bcl-2 protein were the same in first trimester and term cytotrophoblasts. Culture with TNF-alpha/IFN-gamma and EGF did not alter expression of either Bcl-2 protein or of the pro-apoptotic Bcl-2 family member Bak. Double label flow cytometric analysis that measured apoptosis and Bcl-2 content simultaneously showed that cells expressing low levels of Bcl-2 underwent TNF-alpha/IFN-gamma-induced apoptosis at a higher frequency than cells expressing lower levels. We conclude that Bcl-2 is expressed in cytotrophoblasts, that its expression is constitutive and that modulation of its expression levels does not mediate cytokine and growth factor regulation of apoptosis in these cells.


Asunto(s)
Vellosidades Coriónicas/efectos de los fármacos , Citocinas/antagonistas & inhibidores , Factor de Crecimiento Epidérmico/farmacología , Regulación del Desarrollo de la Expresión Génica/fisiología , Genes bcl-2 , Trofoblastos/patología , Apoptosis/efectos de los fármacos , Células Cultivadas , Vellosidades Coriónicas/patología , Femenino , Humanos , Interferón gamma/antagonistas & inhibidores , Proteínas de la Membrana/metabolismo , Embarazo , Proteínas Gestacionales/metabolismo , Primer Trimestre del Embarazo , Tercer Trimestre del Embarazo , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Proteína Destructora del Antagonista Homólogo bcl-2
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