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Len Cintra Azucena Aguilar Leticia Granados Agustín Galvn Thomas Kemper William DeBassio Janina Galler Peter Morgane Pilar Durn Sofía Díaz-Cintra 《Hippocampus》1997,7(2):192-203
The present study was undertaken to investigate the effect of prenatal protein deprivation on area CA1 hippocampal pyramidal cells on postnatal (P) days 15, 30, 90 and 220 using Golgi techniques. Age related changes in both groups and diet related changes between groups were assessed. There were significant diet effects at all four ages, with one of 12 different measurements showing a significant diet effect on P15, five on P30, one on P90, and seven on P220. The most marked effect of the diet was on pyramidal cell dendrite spine density in the stratum moleculare and stratum radiatum, with a different pattern of diet effects in the two strata. In pyramidal cell dendrites in the stratum moleculare, there was a deficit in spine density that was significant at three of the four ages and there were similar age-related changes in the two diet groups. Spines on pyramidal cell dendrites in the stratum radiatum showed a lack of synchrony of age-related changes in the two diet groups, with an increased spine density in the malnourished rats on P30 and a widening deficit in this parameter on P90 and P220. The bimodal distribution to these changes, with most marked deficits occurring on P30 and P220, with an intervening period of apparent “catch-up” on P90, is of interest and may be a significant brain adaptation to malnutrition. The present study is the final of three morphometric studies on the effect of prenatal protein restriction on three key neurons in the hippocampal trisynaptic circuit. When compared to our previous studies on the dentate granule cell and the CA3 pyramidal cell, it is noted that there is an effect of the low protein diet on all these neurons, with the most marked effect on the predominantly postnatally generated dentate granule cells. Hippocampus 7:192–203, 1997. © 1997 Wiley-Liss, Inc. 相似文献
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Breast Cancer Metastasis Associations with Clinicopathological Characteristics in Mexican Women Younger than 40 Years of Age
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Azucena Moreno RosalesMiguel Corres MolinaJacqueline Góngora MooPablo Romero MorelosCindy Bandala 《Asian Pacific journal of cancer prevention》2016,17(11):5019-5023
Background: In Mexico, breast cancer (BCa) is in first place regarding cancer mortality and has been established as a priority health issue. The incidence of metastasis from BCa is very high and presents as the principal mortality factor among women younger than 40 years of age. OBJECTIVE. To determine any associations between clinicopathological characteristics and metastasis in Mexican women under 40 years of age. Methods: During the 2010–2015 period, a total of 180 female BCa cases seen at the Navy General High Specialty Hospital, SEMAR, in Mexico City; we collected information on 20 patients with BCa younger than 40 years of age. Statistical analyses were conducted using the Kolmogorov–Smirnov, Students t, Fisher, Chi square, and Mantel–Haenszel tests. Results: The prevalence of women with BCa younger than the age of 40 years during the 2010–2015 period was 13.3%. We found a high frequency of obesity in of these cases (>75%); 100% of obese patients with a history of smoking presented with metastasis (p <0.05). In addition, the hormone phenotype was important; HER2-positive cases were 12 times more likely tto exhibit metastasis (p <0.05), while expression of estrogen and progesterone receptors appeared to be protective. Diabetes mellitus in combination with smoking was also a risk factor for development of metastasis (p <0.05). Conclusion: In this study, we obtained essential data regarding risk of metastasis in young breast cancer cases which could be useful for predicting disease evolution and treatment response. 相似文献
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INTRODUCTION: Malaria continues to represent a huge global health burden on the most vulnerable populations. The Intermittent Preventive Treatment (IPT) strategy has been shown to be an efficacious intervention in preventing most of the deleterious effects of malaria in pregnant women and infants. Yet, the effectiveness of the IPT strategy may be impaired by the increasing resistance to sulfadoxine-pyrimethamine (SP), and the scarcity of alternative antimalarial drugs. AREAS COVERED: This review examines all the available information on IPT, in an aim to provide the scientific community with a framework to understand the benefits and limitations of this malaria control strategy. It includes the understanding of the historical background of the IPT strategy, the drug's mechanisms of actions, updated information on current available evidence, the implications of drug resistance and choice of alternative drugs, and a comprehensive discussion on the perspectives of IPT for malaria control in pregnant women and infants. EXPERT OPINION: IPT in pregnancy and infants is a cost-effective strategy that can contribute significantly to the control of malaria in endemic areas. Monitoring its effectiveness will allow tracking of progress, evaluation of the adequacy of currently used drugs and will highlight the eventual need for new therapies or alternative interventions. 相似文献
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Pérez-Molina JA Rodríguez-Guardado A Soriano A Pinazo MJ Carrilero B García-Rodríguez M Salas J Torrús D Soler-Ferrer C Puente S Haro-González JL Martín-Rabadán P Gascon J;Chagas Study Group Of The SEMTSI 《HIV clinical trials》2011,12(6):287-298
As a result of population migration, Chagas disease is no longer limited to the North and South American continents. In HIV-infected patients, chronic infection by Trypanosoma cruzi behaves as an opportunistic infection in severely immunosuppressed patients and is responsible for high morbidity and mortality. Unlike other opportunistic infections, information on the natural history, diagnosis, treatment, and prevention of Chagas disease is scarce. Spain has the highest number of cases of Chagas disease outside the North and South American continents, and coinfection with HIV is increasingly prevalent. In this article, the Spanish Society for Tropical Medicine and International Health (Sociedad Espa?ola de Medicina Tropical y Salud Internacional) reviews the current situation of coinfection with HIV and T. cruzi infection and provides guidelines on the diagnosis, treatment, and prevention in areas where Chagas disease is not endemic. It also identifies areas of uncertainty where additional research is necessary. 相似文献
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Jorge Ramón Padilla-Gutiérrez Claudia Azucena Palafox-Sánchez Yeminia Valle Gerardo Orozco-Barocio Edith Oregón-Romero Mónica Vázquez-Del Mercado Héctor Rangel-Villalobos Mara Anaís Llamas-Covarrubias José Francisco Mu?oz-Valle 《Clinical and experimental medicine》2011,11(1):11-17
Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by the presence of autoantibodies against
nuclear autoantigens as well as cytoplasmic and circulating proteins. Recent studies have demonstrated mechanisms responsible
for modulation of the immune response by the plasminogen activator inhibitor-1 (PAI-1). Furthermore, the endogenous PAI-1
has shown to promote a Th2 immune response. We assessed the −844 G>A and HindIII C>G PAI-1 polymorphisms in SLE. In a case–control study of 71 SLE patients classified according to ACR criteria and 71 healthy subjects
(HS). The A allele of −844 PAI-1 polymorphism showed a significant difference in SLE patients (41%) when compared with HS (27%) [P = 0.01; OR = 1.8, 95%, CI = 1.1–3.0]. In addition, the −844 G>A PAI-1 polymorphism was associated with increased risk for SLE in a dominant genetic model (G/G vs. G/A + A/A; OR = 2.3, 95% CI = 1.14–4.44).
Also, anti-RNP positive antibodies in SLE were associated with G/G −844 PAI-1 genotype. The HindIII polymorphism did not show any differences. The haplotype analysis showed that the AC haplotype confers susceptibility
to SLE (OR = 3.1, 95% CI, 1.45–6.52; P = 0.003). The AC haplotype of the −844 and HindIII PAI-1 polymorphism might be an additional susceptibility factor to SLE in Mexicans. 相似文献
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Méndez M Méndez-López M López L Begega A Aller MA Arias J Arias JL 《Acta neurologica Belgica》2010,110(3):246-254
Patients with liver dysfunction often suffer from hepatic encephalopathy (HE), a neurological complication that affects attention and memory. Various experimental animal models have been used to study HE, the most frequently used being the portocaval shunt (PCS). In order to determine brain substrates of cognitive impairment in this model, we assessed reversal learning and c-Fos expression in a rat model of portosystemic derivation. PCS and sham-operated rats (SHAM) were tested for reversal learning. Brains were processed for c-Fos immunocytochemistry. The total number of c-Fos positive nuclei was quantified in the prefrontal cortex and hippocampus. The spatial reference memory task showed no differences between groups in escape latencies. The no-platform probe test showed that both the PCS and the SHAM learned the location of platform. However, the PCS group perseverated in the old target during reversal. The PCS group presented less c-Fos- positive cells in prelimbic cortex, CA1 and dentate gyrus of the dorsal hippocampus than SHAM. Overall, these results suggest that this specific model of portosystemic hepatic encephalopathy produces reversal learning impairment that could be linked to dysfunction in neuronal activity in the prefrontal cortex and hippocampus. 相似文献