Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 49
Filtrar
Más filtros

Intervalo de año de publicación
1.
Environ Dev Sustain ; : 1-20, 2023 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-37362987

RESUMEN

This paper provides a mathematical optimization strategy for optimal municipal solid waste management in the context of the COVID-19 epidemic. This strategy integrates two approaches: optimization and machine learning models. First, the optimization model determines the optimal supply chain for the municipal waste management system. Then, machine learning prediction models estimate the required parameters over time, which helps generate future projections for the proposed strategy. The optimization model was coded in the General Algebraic Modeling System, while the prediction model was coded in the Python programming environment. A case study of New York City was addressed to evaluate the proposed strategy, which includes extensive socioeconomic data sets to train the machine learning model. We found the predicted waste collection over time based on the socioeconomic data. The results show trade-offs between the economic (profit) and environmental (waste sent to landfill) objectives for future scenarios, which can be helpful for possible pandemic scenarios in the following years. Supplementary Information: The online version contains supplementary material available at 10.1007/s10668-023-03354-2.

2.
Socioecon Plann Sci ; 87: 101559, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37255586

RESUMEN

This work presents a multi-objective optimization strategy for fair vaccine allocation through different fairness schemes. The proposed approach considers a diverse series of parameters related to different public health data and social behaviors that influence the correct distribution of vaccines, such as corruption and crime. Simultaneously, the formulation includes prioritizing those groups with the highest risk based on the epidemiological traffic light. Furthermore, the presented strategy involves different budget constraints that allow identifying trade-off solutions through Pareto fronts. Therefore, vaccine allocations are obtained by combining fairness concepts with multi-objective optimization. The applicability of the model is illustrated using the case study of Mexico. The solution to the proposed scenarios was carried out using different justice schemes and an economic objective function. The results show the compromises between a satisfaction index and costs, which are shown through Pareto optimal solutions that allow selecting the solutions that balance the objectives. The solutions provided by the social welfare scheme suggest a greater allocation of vaccines to those states with higher epidemiological risk, which may be helpful in the first stage of vaccination. On the other hand, the Rawlsian scheme provides more balanced solutions that can be useful in situations with lower rates of infection. Finally, the Nash scheme is the one that provides the most balanced solutions, favoring to a lesser extent the areas with the highest epidemiological risk, which may be useful in the later stages of vaccination.

3.
Chem Eng Process ; 176: 108942, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35479187

RESUMEN

There have been many problems generated by the COVID-19 pandemic. One of them is the worrying increase in the generation of medical waste due to the great risk they represent for health. Therefore, this work proposes a mathematical model for optimal solid waste management, proposing a circular value chain where all types of waste are treated in an intensified industrial park. The model selects the processing technologies and their production capacity. The problem was formulated as a mixed-integer linear programming problem to maximize profits and the waste processed, minimizing environmental impact. The proposed strategy is applied to the case study of the city of New York, where the increase in the generation of medical waste has been very significant. To promote recycling, different tax rates are proposed, depending on the amount of waste sent to the landfill. The results are presented on a Pareto curve showing the trade-off between profits and processed waste. We observed that the taxes promote recycling, even of those wastes that are not very convenient to recycle (from an economic point of view), favoring profits, reducing the environmental impact, and the risk to health inherent to the medical waste.

4.
Br J Cancer ; 119(8): 915-921, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30318508

RESUMEN

BACKGROUND: Optimal duration of anticoagulation for cancer-associated thrombosis (CAT) remains unclear. This study assessed D-dimer (DD) and high-sensitivity C-reactive protein (hs-CRP) levels after the withdrawal of anticoagulation treatment to predict the risk of venous thromboembolism (VTE) recurrence among patients with CAT. METHODS: Prospective, multicentre study to evaluate CAT with ≥3 months of anticoagulation that was subsequently discontinued. Blood samples were taken when patients stopped the anticoagulation and 21 days later to determine the DD and hs-CRP levels. All patients were followed up for 6 months to detect VTE recurrence. RESULTS: Between 2013 and 2015, 325 patients were evaluated and 114 patients were ultimately enrolled in the study. The mean age was 62 ± 14 years and nearly 40% had metastasis. Ten patients developed VTE recurrence within 6 months (8.8%, 95% confidence interval [CI]: 4.3-15.5%). The DD and hs-CRP levels after 21 days were associated with VTE recurrence. The subdistribution hazard ratios were 9.82 for hs-CRP (95% CI: 19-52) and 5.81 for DD (95% CI: 1.1-31.7). CONCLUSIONS: This study identified that hs-CRP and DD were potential biomarkers of VTE recurrence after discontinuation of anticoagulation in CAT. A risk-adapted strategy could identify low-risk patients who may benefit from discontinuation of anticoagulation.


Asunto(s)
Anticoagulantes/administración & dosificación , Proteína C-Reactiva/análisis , Productos de Degradación de Fibrina-Fibrinógeno/análisis , Neoplasias/patología , Tromboembolia Venosa/prevención & control , Trombosis de la Vena/prevención & control , Privación de Tratamiento/estadística & datos numéricos , Anticoagulantes/uso terapéutico , Esquema de Medicación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/irrigación sanguínea , Estudios Prospectivos , Recurrencia , Medición de Riesgo , Factores de Riesgo , Prevención Secundaria/métodos , Tromboembolia Venosa/tratamiento farmacológico , Trombosis de la Vena/tratamiento farmacológico
6.
J Am Chem Soc ; 136(45): 15833-6, 2014 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-25340304

RESUMEN

A novel Cu-catalyzed diastereo- and enantioselective desymmetrization of cyclopropenes to afford nonracemic cyclopropylboronates is described. Trapping the cyclopropylcopper intermediate with electrophilic amines allows for the synthesis of cyclopropylaminoboronic esters and demonstrates the potential of the approach for the synthesis of functionalized cyclopropanes.


Asunto(s)
Ácidos Borónicos/química , Ácidos Borónicos/síntesis química , Cobre/química , Ciclopropanos/química , Técnicas de Química Sintética , Estereoisomerismo , Temperatura
7.
Eur J Appl Physiol ; 114(6): 1123-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24553907

RESUMEN

BACKGROUND: Despite a growing clinical interest in determining the heart rate recovery (HRR) response to exercise, the limits of a normal HRR have not yet been well established. PURPOSE: This study was designed to examine HRR following a controlled maximal exercise test in healthy, physically active adult men. METHODS: The subjects recruited (n = 789) performed a maximal stress test on a treadmill. HRR indices were calculated by subtracting the first and third minute heart rates (HRs) during recovery from the maximal HR obtained during stress testing and designated these as HRR-1 and HRR-3, respectively. The relative change in HRR was determined as the decrease in HR produced at the time points 1 and 3 min after exercise as a percentage of the peak HR (%HRR-1/HR(peak) and %HRR-3/HR(peak), respectively). Percentile values of HRR-1 and HRR-3 were generated for the study population. RESULTS: Mean HHR-1 and HHR-3 were 15.24 ± 8.36 and 64.58 ± 12.17 bpm, respectively, and %HRR-1/HR(peak) and %HRR-3/HR(peak) were 8.60 ± 4.70 and 36.35 ± 6.79%, respectively. Significant correlation was detected between Peak VO2 and HRR-3 (r = 0.36; p < 0.001) or %HRR-3/HR(peak) (r = 0.23; p < 0.001). CONCLUSIONS: Our study provides normality data for HRR following a maximal Ergometry test obtained in a large population of physically active men.


Asunto(s)
Tolerancia al Ejercicio , Ejercicio Físico/fisiología , Frecuencia Cardíaca , Adulto , Humanos , Masculino , Persona de Mediana Edad
8.
Influenza Other Respir Viruses ; 18(1): e13243, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38204584

RESUMEN

Background: Influenza A(H3N2) viruses dominated early in the 2022-2023 influenza season in Europe, followed by higher circulation of influenza A(H1N1)pdm09 and B viruses. The VEBIS primary care network estimated the influenza vaccine effectiveness (VE) using a multicentre test-negative study. Materials and Methods: Primary care practitioners collected information and specimens from patients consulting with acute respiratory infection. We measured VE against any influenza, influenza (sub)type and clade, by age group, by influenza vaccine target group and by time since vaccination, using logistic regression. Results: We included 38 058 patients, of which 3786 were influenza A(H3N2), 1548 influenza A(H1N1)pdm09 and 3275 influenza B cases. Against influenza A(H3N2), VE was 36% (95% CI: 25-45) among all ages and ranged between 30% and 52% by age group and target group. VE against influenza A(H3N2) clade 2b was 38% (95% CI: 25-49). Overall, VE against influenza A(H1N1)pdm09 was 46% (95% CI: 35-56) and ranged between 29% and 59% by age group and target group. VE against influenza A(H1N1)pdm09 clade 5a.2a was 56% (95% CI: 46-65) and 79% (95% CI: 64-88) against clade 5a.2a.1. VE against influenza B was 76% (95% CI: 70-81); overall, 84%, 72% and 71% were among 0-14-year-olds, 15-64-year-olds and those in the influenza vaccination target group, respectively. VE against influenza B with a position 197 mutation of the hemagglutinin (HA) gene was 79% (95% CI: 73-85) and 90% (95% CI: 85-94) without this mutation. Conclusion: The 2022-2023 end-of-season results from the VEBIS network at primary care level showed high VE among children and against influenza B, with lower VE against influenza A(H1N1)pdm09 and A(H3N2).


Asunto(s)
Subtipo H1N1 del Virus de la Influenza A , Virus de la Influenza A , Vacunas contra la Influenza , Gripe Humana , Niño , Humanos , Europa (Continente)/epidemiología , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/genética , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Atención Primaria de Salud , Eficacia de las Vacunas , Recién Nacido , Lactante , Preescolar , Adolescente , Adulto Joven , Adulto , Persona de Mediana Edad
9.
Neurosci Lett ; 813: 137413, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37541318

RESUMEN

Uncertainty persists regarding the specific chemical causal factors and their corresponding behavioral effects in anxiety disorders. Commonly employed first-line treatments for anxiety target G protein-coupled receptors (GPCRs), including inhibitors of monoaminergic systems. Alternatively, emerging natural bioactive strategies offer potential for mitigating adverse effects. Recent investigations have implicated adenosine in anxiety-triggering mechanisms, while eritadenine, an adenosine analog derived from Shiitake mushroom, has displayed promising attributes. This study explores eritadenine's potential as a bioactive substance for anxiety disorders in mice, employing behavioral tests, pentobarbital-sleep induction, and molecular docking. Behavioral test results reveal a pronounced anxiolytic and sedative-hypnotic pharmacological effect of eritadenine. Our findings suggest that eritadenine may modulate locomotor functions mediated by adenosine receptors, with a stronger affinity for binding to A2AAR over A1AR, thus eliciting these effects.


Asunto(s)
Trastornos de Ansiedad , Hipnóticos y Sedantes , Ratones , Animales , Simulación del Acoplamiento Molecular , Adenosina
10.
Rev Med Inst Mex Seguro Soc ; 50(3): 285-8, 2012.
Artículo en Español | MEDLINE | ID: mdl-23182258

RESUMEN

OBJECTIVE: to describe cardiovascular risk factors in pediatric patients of the General Hospital Zone 58 and its relationship with metabolic abnormalities. METHODS: we studied a population of 30 healthy; children randomized. We measured weight, height, body mass index, blood pressure, waist circumference, determination of blood glucose, total cholesterol, HDL, LDL, triglycerides and uric acid. We applied a structured questionnaire about: how many hours a day the child watch television, hours of sleeping, birth weight, consumption of junk food, plus additional questions to investigate family history of cardiovascular disease. RESULTS: the group consisted of 17 girls (56 %) and 13 children (44 %), average age: 9.7 years. Patients who had at least one abnormal laboratory result were 27 (90 %). Cardiovascular risk factors showed an arithmetic mean birth weight 3175 g, 3.6 h hours of watching TV, sleep diary 8.9, lots of junk food every day 2.9. 15 patients had normal BMI, 5 more than the 95 centile and 7 below the 10 centile. CONCLUSIONS: the main factor that determined metabolic disorders was family history of cardiovascular disease or lipid disorders.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Metabólicas/complicaciones , Niño , Estudios Transversales , Femenino , Humanos , Masculino , Estudios Prospectivos , Factores de Riesgo
11.
SAGE Open Med ; 10: 20503121221108556, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35784672

RESUMEN

Objective: We aimed to assess the prevalence and clinical characteristics of SARS-CoV-2 reinfections in a Spanish region. Methods: This is a retrospective observational study in all patients with SARS-CoV-2 infections in the Lleida health region from 1 March to 30 November 2020. Reinfections were classified as patients with positive SARS-CoV-2 PCR tests separated by at least 90 days plus a negative test result between both infection episodes. Primary and secondary outcomes: The primary outcome was the percentage of SARS-CoV-2 reinfections among all SARS-CoV-2 infections detected during our study period. Secondary outcomes were the clinical and sociodemographic characteristics of patients with SARS-CoV-2 reinfections. Results: Of the 27,758 patients diagnosed with SARS-CoV-2 infection in the study period, 14 were identified as coronavirus reinfection (0.050%). Of the reinfected sample, 12 patients (85.7%) were women. The median age was 41.5 years. Two patients died in the second coronavirus episode. Conclusion: The reinfection rate of SARS-CoV-2 in the Spanish region Lleida was relatively low during the observational period in 2020 (less than 1%). These data are in line with the notion that previous SARS-CoV-2 infections may offer a significant protection by so called natural immunity.

12.
Cancers (Basel) ; 14(11)2022 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-35681751

RESUMEN

The most appropriate duration of anticoagulant treatment for cancer-associated venous thromboembolism (CAT) remains unclear. We have conducted a prospective multicenter study in CAT patients with more than 6 months of anticoagulant treatment to predict the risk of venous thromboembolism (VTE) recurrence after anticoagulation discontinuation. Blood samples were obtained when patients stopped the anticoagulation, at 21 days and at 90 days. In each sample we assessed different coagulation-related biomarkers: D-dimer (DD), high-sensitivity C-reactive protein (hs-CRP), P-selectin (PS), phospholipids, soluble tissue factor, factor VIII and the thrombin generation test. It was evaluated 325 CAT patients and 166 patients were included in the study, mean age 64 ± 17 years. VTE recurrence until 6 months after stopping anticoagulation treatment was 9.87% [95% confidence interval (CI): 6−15]. The biomarkers sub-distribution hazard ratios were 6.32 for ratio DD basal/DD 21 days > 2 (95% CI: 1.82−21.90), 6.36 for hs-CRP > 4.5 (95% CI: 1.73−23.40) and 5.58 for PS > 40 (95% CI: 1.46−21.30) after 21 days of stopping anticoagulation. This is the first study that has identified the DD ratio, hs-CRP and PS as potential biomarkers of VTE recurrence in cancer patients after the discontinuation of anticoagulation treatment. A risk-adapted strategy may allow the identification of the optimal time to withdraw the anticoagulation in each CAT patient.

13.
Biol Res ; 44(3): 259-67, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22688913

RESUMEN

The rat prostate comprises dorsal, ventral and lateral lobes that are morphologically and biochemically distinct. Lesions to these structures are expected to affect the quality of the ejaculate and male fertility. In experiment 1, we analyzed ejaculate parameters of males that had chemical lesions of the dorsal or ventral lobes. At pre-lesion and at 5 and 20 days post-lesion males were mated, and after ejaculation, seminal fluid and seminal plug were obtained from the mated females. In experiment 2, the ventral lobes were ablated, and the ejaculate was analyzed. In experiment 3, the fertility of males with chemically-lesioned dorsal lobes or ablation of the ventral lobes was evaluated. Chemical lesion of the dorsal lobe prevented the adhesion of the seminal plug to vaginal walls. When these males were tested at 5-days postlesion, no sperm were found in uterus, and at 20-days post-lesion, the few sperm encountered showed slow progressive motility. None of the females that mated with dorsal lobe-lesioned males became pregnant. However, chemical lesion or ablation of the ventral lobes did not affect ejaculate or fertility. Our results indicate that the dorsal prostatic lobes are indispensable for reproductive success in males, and define parameters of ejaculate with which fertility can be estimated.


Asunto(s)
Copulación/fisiología , Eyaculación/fisiología , Fertilidad/fisiología , Próstata/anatomía & histología , Semen/fisiología , Motilidad Espermática , Animales , Adhesión Celular , Femenino , Masculino , Embarazo , Índice de Embarazo , Próstata/efectos de los fármacos , Próstata/patología , Ratas , Ratas Wistar , Análisis de Semen , Vesículas Seminales/fisiología , Útero/fisiología
14.
J Sports Sci Med ; 10(3): 559-64, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-24150633

RESUMEN

The purpose of this study was to analyze the effects of 2 days/week versus 4 days/week of Whole Body Vibration (WBV) during eight weeks of WBV training on health-related quality of life (SF-36), balance and lower body strength, as well as short-term detraining (3 weeks) on balance and lower body strength among older adults. Thirty-four older adults were randomly assigned to a control group (Control; n = 11) or to one of the vibration training groups: WBV 2 days/week (WBV_2d; n = 11) or WBV 4 days/week (WBV_4d; n = 12). The WBV groups exercised for 8 weeks, following 3 weeks of detraining. Lower body strength increased significantly (p < 0.05) for both groups, WBV_2d and WBV_4d, after 8-week training. A significant reduction in strength was observed following 3 weeks of detraining only in WBV_2d group (p < 0.05). All variables of the SF-36 and the balance test did not change after intervention in any group. 2 days/week and 4 days/week of WBV during 8 weeks showed the same improvements on muscle strength. 3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV. Key points2 days and 4 days per week of WBV training during 8 weeks showed the same improvements on muscle strength.3 weeks of detraining did not reverse the gains in strength made during 32 sessions of WBV exercise.3 weeks of detraining did reverse the gains in strength made during 16 sessions of WBV exercise.

15.
Front Psychol ; 11: 1854, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32982824

RESUMEN

The latest research in Spain indicates that the most advanced neuromarketing consulting companies in the sector are those that have been able to innovate in the development of their own technologies and methodologies. Despite their reduced volume of business compared to total investment in marketing and market research in our country, there are signs that suggest these companies have great potential to improve this sector, which is still to be explored. For this reason, this research straddling the ethnographic method and the theoretical-descriptive method aims to help us better understand the characteristic features of this sector by actively listening to the professional voices that lead it. Its epistemological value lies in its contribution to understanding the business culture related to the professional development of neuromarketing in our country today. The study shows that the main human resources strategy of neuromarketing consulting companies is based on the creation of multidisciplinary work teams. In addition, most of them develop data analysis software, which they can safeguard under various types of copyright, and on other occasions they manage to patent them, to later apply them to the objectives and purposes of their company. This would also explain the widespread use of certain procedures and resources by the vast majority of the consulting companies investigated. Thus, the trend in the market is the implementation of different synchronization software to the available technological and methodological resources. Others have even gone so far as to create a new technological support to incorporate methodologies already in use. Therefore, this gives them exclusivity in their services and the necessary competitive advantage over their competitors. Among other factors, these inferences about how this sector really works are very likely to be very useful in the academic field, which will constitute a further step in generating critical thinking and in expanding the frontiers of knowledge around this discipline.

16.
Waste Manag ; 115: 15-24, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32721856

RESUMEN

Municipal solid waste (MSW) management is an important but complex logistical problem. The deployment of MSW management systems is hindered by the ever-growing generation of waste and the often insufficient infrastructure to manage, process, and dispose of waste. This paper presents a coordinated framework for complex MSW management systems. The framework accommodates multiple key stakeholders in MSW systems, such as suppliers of waste, consumers of waste and derived products, and providers of transportation and processing services. Here, the stakeholders submit bids to a coordinator that solves an optimization problem to determine allocations and clearing prices that maximize the collective profit for all stakeholders and that balance supply and demand for waste and products. Furthermore, the clearing process guarantees that the individual profits are non-negative (no stakeholder loses money). Notably, the framework operates as a competitive market that accelerates transactions between stakeholders and that handles complex logistical constraints that would be difficult to handle in peer-to-peer transactions. The framework also facilitates the integration of policy incentives and the monetization of environmental impacts. In this regard, we evaluate a tax applied to open dump disposal. To illustrate the applicability, an MSW system in Mexico was analyzed as a case study. Results reveal that taxation can be used to incentivize the provision of services for all stakeholders. Specifically, we found that an appropriate tax can completely avoid disposal in open dumps. A tax of 5.1 USD/tonne was identified as the minimum penalization that avoids diverting waste to open dumps.


Asunto(s)
Eliminación de Residuos , Administración de Residuos , Ciudades , México , Residuos Sólidos , Transportes
17.
J Stroke Cerebrovasc Dis ; 18(1): 11-6, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19110138

RESUMEN

INTRODUCTION: Cerebrovascular disease is among the 4 main causes of mortality in Spain. The objective of this study was to estimate the incidence of stroke and to describe the principal risk factors and other clinical and epidemiologic patterns found in patients. METHODS: Doctors from the Spanish sentinel health network recorded the episodes of acute cerebrovascular diseases in 2005 in a population of 201,205 inhabitants older than 14 years. The information of the patients (age and sex) and the episode (e.g., duration, symptoms, origin, medical attention, risk factors) was collected on a standard form. RESULTS: The estimated incidence rate of stroke was 141 cases per 100,000 inhabitants (confidence interval [CI] 95%: 125-158), 134 (95% CI: 112-157) in women and 148 (95% CI: 124-172) in men. The incidence increases significantly from the age of 65 years and men younger than this have higher rates than women. In all, 12% of patients with stroke die within the first 24 hours. CONCLUSIONS: Incidence of cerebrovascular disease in Spain is below that recorded in other countries. There is no difference according to sex, but incidence among young and middle-aged men is greater than that among women. Significant variations from some population groups to others are observed, maybe because of the difference in the prevalence of risk factors.


Asunto(s)
Accidente Cerebrovascular/epidemiología , Adolescente , Adulto , Distribución por Edad , Factores de Edad , Anciano , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Medición de Riesgo , Factores de Riesgo , Vigilancia de Guardia , Distribución por Sexo , Factores Sexuales , España/epidemiología , Accidente Cerebrovascular/etiología , Accidente Cerebrovascular/mortalidad , Factores de Tiempo , Adulto Joven
18.
Arch Med Res ; 50(6): 393-399, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31689664

RESUMEN

BACKGROUND: Night shift work involving circadian disruption has been associated with increased breast cancer rates in some epidemiological studies, but the evidence is still on debate. AIM OF THE STUDY: The objective of this study is to assess the association between night shift work and breast cancer in Mexican women. METHODS: A Case-control study was conducted with incident cases of breast cancer at the Instituto de Seguridad Social del Estado de México y Municipios. Cases were interviewed about past exposures prior to the final diagnosis. Controls were women without breast cancer matched on multiple sociodemographic characteristics. RESULTS: 101 cases and 101 matched controls were interviewed; this small sample size provided consistent, but wide estimates of the assessed associations. The multivariate conditional logistic regression showed that breast-feeding was associated with reduced risk for breast cancer (OR 0.12; 95% CI: 0.02-0.60); women who experienced early menarche (12 years) were more likely to develop breast cancer (OR 18.58; 95% CI 18: 2.19-148). Women who worked at night were more likely to develop breast cancer compared to women who never did (OR = 8.58; 95% CI: 2.19-33.8). CONCLUSIONS: Our results are consistent with studies from other countries, which positively associated night shift work with breast cancer.


Asunto(s)
Neoplasias de la Mama/etiología , Ritmo Circadiano/fisiología , Menarquia/fisiología , Horario de Trabajo por Turnos/efectos adversos , Tolerancia al Trabajo Programado/fisiología , Adulto , Lactancia Materna , Estudios de Casos y Controles , Femenino , Humanos , Modelos Logísticos , México , Persona de Mediana Edad , Factores de Riesgo , Conducta de Reducción del Riesgo
19.
Bone ; 42(2): 432-8, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18032124

RESUMEN

Cranial vault and facial sutures interpose between mineralized bones of the skull, and may function analogously to appendicular and cranial base growth plates. However, unlike growth plates that are composed of chondrocyte lineage, cranial and facial sutures possess heterogeneous cell lineages such as mesenchymal cells, fibroblasts, and osteoblasts, in addition to vascular-derived cells. Despite recently intensified effort, the biological responses of intramembranous bone and sutures to mechanical loading are not well understood. This study was designed to investigate whether brief doses of tensile or compressive forces induce modeling and growth responses of intramembranous bone and sutures. In different groups of growing rabbits in vivo, cyclic tensile or compressive forces at 1 N and 8 Hz were applied to the maxilla for 20 min/day over 12 consecutive days. Computerized histomorphometric analyses revealed that the average sutural widths of both the premaxillomaxillary suture (PMS) and nasofrontal suture (NFS) loaded in either tension or compression were significantly higher than age- and sex-matched sham controls (P<0.01). The average cell densities of tension- or compression-loaded PMS and NFS were significantly higher than sham controls (P<0.01). The average osteoblast occupied sutural bone surface loaded under tension was significantly higher than that of sham control (P<0.05). Interestingly, tensile loading significantly reduced the average osteoclast surface, in comparison to sham control (P<0.05). For the NFS, tensile loading significantly increased the average osteoblast occupied sutural bone surface, in comparison with that of sham control (P<0.05). Also for the NFS suture, compression significantly reduced the average sutural osteoclast surface in comparison with sham control (P<0.05). Taken together, the present data suggest that high-frequency cyclic forces in either tension or compression induce modeling and growth changes in cranial sutures. Due to the structural complexity of cranial vault and facial sutures, either tensile or compressive forces likely are transmitted as shear stresses and upregulate genes and gene products responsible for sutural growth.


Asunto(s)
Huesos/citología , Huesos/fisiología , Animales , Resorción Ósea , Recuento de Células , Masculino , Osteogénesis , Conejos , Estrés Mecánico , Soporte de Peso
20.
Org Lett ; 19(23): 6272-6275, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-29131637

RESUMEN

In this report, the enantioselective, copper-catalyzed borylation of ß-amidoacrylates is disclosed. A broad variety of biologically important α-aminoboronates has been prepared with consistently high levels of enantiocontrol using an inexpensive copper catalyst and a commercially available chiral ligand. The method can be applied to the synthesis of novel boron-containing dipeptides and hemiboronates.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA