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1.
Ann Surg Oncol ; 29(6): 3911-3920, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35041098

RESUMEN

BACKGROUND: The Tumor Location-Modified Laurén Classification (MLC) system combines Laurén histologic subtype and anatomic tumor location. It divides gastric tumors into proximal non-diffuse (PND), distal non-diffuse (DND), and diffuse (D) types. The optimum classification of patients with Laurén mixed tumors in this system is not clear due to its grouping with both diffuse and non-diffuse types in previous studies. The clinical relevance of the MLC in a Western population has not been examined. METHODS: A cohort study investigated 404 patients who underwent gastrectomy for gastric adenocarcinoma between 2005 and 2020. The classification of Laurén mixed tumors was evaluated using receiver operating characteristic (ROC) curve analysis and comparison of clinicopathologic characteristics (chi-square). Survival analysis was performed using multivariable Cox regression. RESULTS: The ROC curve analysis demonstrated a slightly higher area under the curve value for predicting survival when Laurén mixed tumors were grouped with intestinal-type rather than diffuse-type tumors (0.58 vs 0.57). Survival, tumor recurrence, and resection margin positivity in mixed tumors also was more similar to intestinal type. Distal non-diffuse tumors had the best 5-year survival (DND 64.7 % vs PND 56.1 % vs diffuse 45.1 %; p = 0.006) and were least likely to have recurrence (DND 27.0 % vs PND 34.3 % vs diffuse 48.3 %; p = 0.001). Multivariable analysis demonstrated that MLC was an independent prognostic factor for survival (PND: hazard ratio [HR], 1.64; 95 % confidence interval [CI], 1.16-2.32 vs diffuse: HR, 2.20; 95 % CI, 1.56-3.09) CONCLUSIONS: The MLC was an independent prognostic marker in this Western cohort of patients with gastric adenocarcinoma. The patients with PND and D tumors had worse survival than those with DND tumors.


Asunto(s)
Adenocarcinoma , Neoplasias Gástricas , Adenocarcinoma/patología , Estudios de Cohortes , Gastrectomía , Humanos , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Neoplasias Gástricas/patología
2.
Science ; 374(6568): 768-772, 2021 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-34735227

RESUMEN

Clonal hematopoiesis results from enhanced fitness of a mutant hematopoietic stem and progenitor cell (HSPC), but how such clones expand is unclear. We developed a technique that combines mosaic mutagenesis with color labeling of HSPCs to study how acquired mutations affect clonal fitness in a native environment. Mutations in clonal hematopoiesis­associated genes such as asxl1 promoted clonal dominance. Single-cell transcriptional analysis revealed that mutations stimulated expression of proinflammatory genes in mature myeloid cells and anti-inflammatory genes in progenitor cells of the mutant clone. Biallelic loss of one such immunomodulator, nr4a1, abrogated the ability of asxl1-mutant clones to establish clonal dominance. These results support a model where clonal fitness of mutant clones is driven by enhanced resistance to inflammatory signals from their mutant mature cell progeny.


Asunto(s)
Hematopoyesis Clonal , Células Madre Hematopoyéticas/fisiología , Inflamación , Células Mieloides/fisiología , Animales , Sistemas CRISPR-Cas , Citocinas/genética , Citocinas/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , Mutación del Sistema de Lectura , Genes p53 , Inflamación/genética , Mutación , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/genética , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , RNA-Seq , Proteínas Represoras/genética , Selección Genética , Análisis de la Célula Individual , Pez Cebra/embriología , Pez Cebra/genética , Proteínas de Pez Cebra/genética
3.
BMC Public Health ; 21(1): 952, 2021 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-34016085

RESUMEN

BACKGROUND: Improving maternal health has been a primary goal of international health agencies for many years, with the aim of reducing maternal and child deaths and improving access to antenatal care (ANC) services, particularly in low-and-middle-income countries (LMICs). Health interventions with these aims have received more attention from a clinical effectiveness perspective than for cost impact and economic efficiency. METHODS: We collected data on resource use and costs as part of a large, multi-country study assessing the use of routine antenatal screening ultrasound (US) with the aim of considering the implications for economic efficiency. We assessed typical antenatal outpatient and hospital-based (facility) care for pregnant women, in general, with selective complication-related data collection in women participating in a large maternal health registry and clinical trial in five LMICs. We estimated average costs from a facility/health system perspective for outpatient and inpatient services. We converted all country-level currency cost estimates to 2015 United States dollars (USD). We compared average costs across countries for ANC visits, deliveries, higher-risk pregnancies, and complications, and conducted sensitivity analyses. RESULTS: Our study included sites in five countries representing different regions. Overall, the relative cost of individual ANC and delivery-related healthcare use was consistent among countries, generally corresponding to country-specific income levels. ANC outpatient visit cost estimates per patient among countries ranged from 15 to 30 USD, based on average counts for visits with and without US. Estimates for antenatal screening US visits were more costly than non-US visits. Costs associated with higher-risk pregnancies were influenced by rates of hospital delivery by cesarean section (mean per person delivery cost estimate range: 25-65 USD). CONCLUSIONS: Despite substantial differences among countries in infrastructures and health system capacity, there were similarities in resource allocation, delivery location, and country-level challenges. Overall, there was no clear suggestion that adding antenatal screening US would result in either major cost savings or major cost increases. However, antenatal screening US would have higher training and maintenance costs. Given the lack of clinical effectiveness evidence and greater resource constraints of LMICs, it is unlikely that introducing antenatal screening US would be economically efficient in these settings--on the demand side (i.e., patients) or supply side (i.e., healthcare providers). TRIAL REGISTRATION: Trial number: NCT01990625 (First posted: November 21, 2013 on https://clinicaltrials.gov ).


Asunto(s)
Cesárea , Países en Desarrollo , Niño , Femenino , Humanos , Pobreza , Embarazo , Mujeres Embarazadas , Atención Prenatal
4.
BJOG ; 128(9): 1487-1496, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33629490

RESUMEN

OBJECTIVE: Limited data are available from low- and middle-income countries (LMICs) on the relationship of haemoglobin levels to adverse outcomes at different times during pregnancy. We evaluated the association of haemoglobin levels in nulliparous women at two times in pregnancy with pregnancy outcomes. DESIGN: ASPIRIN Trial data were used to study the association between haemoglobin levels measured at 6+0 -13+6  weeks and 26+0 -30+0  weeks of gestation with fetal and neonatal outcomes. SETTING: Obstetric care facilities in Pakistan, India, Kenya, Zambia, The Democratic Republic of the Congo and Guatemala. POPULATION: A total of 11 976 pregnant women. METHODS: Generalised linear models were used to obtain adjusted relative risks and 95% CI for adverse outcomes. MAIN OUTCOME MEASURES: Preterm birth, stillbirth, neonatal death, small for gestational age (SGA) and birthweight <2500 g. RESULTS: The mean haemoglobin levels at 6+0 -13+6  weeks and at 26-30 weeks of gestation were 116 g/l (SD 17) and 107 g/l (SD 15), respectively. In general, pregnancy outcomes were better with increasing haemoglobin. At 6+0 -13+6  weeks of gestation, stillbirth, SGA and birthweight <2500 g, were significantly associated with haemoglobin of 70-89 g/l compared with haemoglobin of 110-129 g/l The relationships of adverse pregnancy outcomes with various haemoglobin levels were more marked at 26-30 weeks of gestation. CONCLUSIONS: Both lower and some higher haemoglobin concentrations are associated with adverse fetal and neonatal outcomes at 6+0 -13+6  weeks and at 26-30 weeks of gestation, although the relationship with low haemoglobin levels appears more consistent and generally stronger. TWEETABLE ABSTRACT: Both lower and some higher haemoglobin concentrations were associated with adverse fetal and neonatal outcomes at 6-13 weeks and 26-30 weeks of gestation.


Asunto(s)
Hemoglobinas/análisis , Recién Nacido Pequeño para la Edad Gestacional , Muerte Perinatal , Nacimiento Prematuro/epidemiología , Mortinato/epidemiología , Adulto , Países en Desarrollo , Índices de Eritrocitos , Femenino , Edad Gestacional , Humanos , Embarazo , Primer Trimestre del Embarazo , Factores de Riesgo
6.
Nat Commun ; 11(1): 6036, 2020 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-33247130

RESUMEN

Human activities are transforming grassland biomass via changing climate, elemental nutrients, and herbivory. Theory predicts that food-limited herbivores will consume any additional biomass stimulated by nutrient inputs ('consumer-controlled'). Alternatively, nutrient supply is predicted to increase biomass where herbivores alter community composition or are limited by factors other than food ('resource-controlled'). Using an experiment replicated in 58 grasslands spanning six continents, we show that nutrient addition and vertebrate herbivore exclusion each caused sustained increases in aboveground live biomass over a decade, but consumer control was weak. However, at sites with high vertebrate grazing intensity or domestic livestock, herbivores consumed the additional fertilization-induced biomass, supporting the consumer-controlled prediction. Herbivores most effectively reduced the additional live biomass at sites with low precipitation or high ambient soil nitrogen. Overall, these experimental results suggest that grassland biomass will outstrip wild herbivore control as human activities increase elemental nutrient supply, with widespread consequences for grazing and fire risk.


Asunto(s)
Biomasa , Pradera , Herbivoria/fisiología , Nitrógeno/análisis , Fósforo/análisis , Intervalos de Confianza , Fertilizantes , Factores de Tiempo
7.
Nat Commun ; 10(1): 4981, 2019 10 31.
Artículo en Inglés | MEDLINE | ID: mdl-31672992

RESUMEN

Soil nitrogen mineralisation (Nmin), the conversion of organic into inorganic N, is important for productivity and nutrient cycling. The balance between mineralisation and immobilisation (net Nmin) varies with soil properties and climate. However, because most global-scale assessments of net Nmin are laboratory-based, its regulation under field-conditions and implications for real-world soil functioning remain uncertain. Here, we explore the drivers of realised (field) and potential (laboratory) soil net Nmin across 30 grasslands worldwide. We find that realised Nmin is largely explained by temperature of the wettest quarter, microbial biomass, clay content and bulk density. Potential Nmin only weakly correlates with realised Nmin, but contributes to explain realised net Nmin when combined with soil and climatic variables. We provide novel insights of global realised soil net Nmin and show that potential soil net Nmin data available in the literature could be parameterised with soil and climate data to better predict realised Nmin.

8.
Ecol Lett ; 22(7): 1136-1144, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31074933

RESUMEN

Sodium is unique among abundant elemental nutrients, because most plant species do not require it for growth or development, whereas animals physiologically require sodium. Foliar sodium influences consumption rates by animals and can structure herbivores across landscapes. We quantified foliar sodium in 201 locally abundant, herbaceous species representing 32 families and, at 26 sites on four continents, experimentally manipulated vertebrate herbivores and elemental nutrients to determine their effect on foliar sodium. Foliar sodium varied taxonomically and geographically, spanning five orders of magnitude. Site-level foliar sodium increased most strongly with site aridity and soil sodium; nutrient addition weakened the relationship between aridity and mean foliar sodium. Within sites, high sodium plants declined in abundance with fertilisation, whereas low sodium plants increased. Herbivory provided an explanation: herbivores selectively reduced high nutrient, high sodium plants. Thus, interactions among climate, nutrients and the resulting nutritional value for herbivores determine foliar sodium biogeography in herbaceous-dominated systems.


Asunto(s)
Pradera , Herbivoria , Sodio , Adaptación Fisiológica , Animales , Nitrógeno , Plantas , Suelo
9.
BJOG ; 125(12): 1591-1599, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29782696

RESUMEN

OBJECTIVE: Ultrasound is widely regarded as an important adjunct to antenatal care (ANC) to guide practice and reduce perinatal mortality. We assessed the impact of ANC ultrasound use at health centres in resource-limited countries. DESIGN: Cluster randomised trial. SETTING: Clusters within five countries (Democratic Republic of Congo, Guatemala, Kenya, Pakistan, and Zambia) METHODS: Clusters were randomised to standard ANC or standard care plus two ultrasounds and referral for complications. The study trained providers in intervention clusters to perform basic obstetric ultrasounds. MAIN OUTCOME MEASURES: The primary outcome was a composite of maternal mortality, maternal near-miss mortality, stillbirth, and neonatal mortality. RESULTS: During the 24-month trial, 28 intervention and 28 control clusters had 24 263 and 23 160 births, respectively; 78% in the intervention clusters received at least one study ultrasound; 60% received two. The prevalence of conditions noted including twins, placenta previa, and abnormal lie was within expected ranges. 9% were referred for an ultrasound-diagnosed condition, and 71% attended the referral. The ANC (RR 1.0 95% CI 1.00, 1.01) and hospital delivery rates for complicated pregnancies (RR 1.03 95% CI 0.89, 1.20) did not differ between intervention and control clusters nor did the composite outcome (RR 1.09 95% CI 0.97, 1.23) or its individual components. CONCLUSIONS: Despite availability of ultrasound at ANC in the intervention clusters, neither ANC nor hospital delivery for complicated pregnancies increased. The composite outcome and the individual components were not reduced. TWEETABLE ABSTRACT: Antenatal care ultrasound did not improve a composite outcome that included maternal, fetal, and neonatal mortality.


Asunto(s)
Servicios de Salud Materno-Infantil , Área sin Atención Médica , Atención Perinatal , Complicaciones del Embarazo/diagnóstico por imagen , Ultrasonografía Prenatal , Adolescente , Adulto , Análisis por Conglomerados , Países en Desarrollo , Femenino , Humanos , Lactante , Mortalidad Infantil , Recién Nacido , Masculino , Mortalidad Materna , Embarazo , Complicaciones del Embarazo/mortalidad , Adulto Joven
10.
BJOG ; 125(2): 131-138, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28139875

RESUMEN

OBJECTIVE: We sought to classify causes of stillbirth for six low-middle-income countries using a prospectively defined algorithm. DESIGN: Prospective, observational study. SETTING: Communities in India, Pakistan, Guatemala, Democratic Republic of Congo, Zambia and Kenya. POPULATION: Pregnant women residing in defined study regions. METHODS: Basic data regarding conditions present during pregnancy and delivery were collected. Using these data, a computer-based hierarchal algorithm assigned cause of stillbirth. Causes included birth trauma, congenital anomaly, infection, asphyxia, and preterm birth, based on existing cause of death classifications and included contributing maternal conditions. MAIN OUTCOME MEASURES: Primary cause of stillbirth. RESULTS: Of 109 911 women who were enrolled and delivered (99% of those screened in pregnancy), 2847 had a stillbirth (a rate of 27.2 per 1000 births). Asphyxia was the cause of 46.6% of the stillbirths, followed by infection (20.8%), congenital anomalies (8.4%) and prematurity (6.6%). Among those caused by asphyxia, 38% had prolonged or obstructed labour, 19% antepartum haemorrhage and 18% pre-eclampsia/eclampsia. About two-thirds (67.4%) of the stillbirths did not have signs of maceration. CONCLUSIONS: Our algorithm determined cause of stillbirth from basic data obtained from lay-health providers. The major cause of stillbirth was fetal asphyxia associated with prolonged or obstructed labour, pre-eclampsia and antepartum haemorrhage. In the African sites, infection also was an important contributor to stillbirth. Using this algorithm, we documented cause of stillbirth and its trends to inform public health programs, using consistency, transparency, and comparability across time or regions with minimal burden on the healthcare system. TWEETABLE ABSTRACT: Major causes of stillbirth are asphyxia, pre-eclampsia and haemorrhage. Infections are important in Africa.


Asunto(s)
Algoritmos , Sistema de Registros , Mortinato/epidemiología , África/epidemiología , Asia/epidemiología , Países en Desarrollo , Femenino , Salud Global , Guatemala/epidemiología , Humanos , Servicios de Salud Materno-Infantil , Embarazo , Complicaciones del Embarazo/epidemiología , Estudios Prospectivos
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