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61.
Triple negative breast cancer has an extremely poor prognosis when chemotherapy is no longer effective. To overcome drug resistance, novel drug delivery systems based on nanoparticles have had remarkable success. We produced a novel nanoparticle component ‘MDC’ from milk-derived colloid. In order to evaluate the anti-cancer effect of MDC, we conducted in vitro and in vivo experiments on cancer cell lines and a primary tumor derived breast xenograft. Doxorubicin (Dox) conjugated to MDC (MDC-Dox) showed higher cancer cell growth inhibition than MDC alone especially in cell lines with high EGFR expression. In a mouse melanoma model, MDC-Dox significantly suppressed tumor growth when compared with free Dox. Moreover, in a primary tumor derived breast xenograft, one of the mice treated with MDC-Dox showed partial regression, while mice treated with free Dox failed to show any suppression of tumor growth. We have shown that a novel nanoparticle compound made of simple milk-derived colloid has the capability for drug conjugation, and serves as a tumor-specific carrier of anti-cancer drugs. Further research on its safety and ability to carry various anti-cancer drugs into multiple drug-resistant primary breast models is warranted.  相似文献   
62.
Working memory abilities significantly decrease with advancing age; hence, the search for factors that may increase or mitigate this decline is critical. Several factors have been identified that influence working memory; however, their effects have been mainly assessed separately and rarely together with other factors in the same sample. We examined 120 variables to search for factors that jointly act as mediators of working memory decay across the adult life span. A sample of 1652 healthy adults was assessed in spatial and verbal working memory domains. Structural equation modeling analyses were conducted to search for potential mediators that intervened between age and working memory. Only 14 and 10 variables reliably mediated spatial and verbal working memory, respectively. Factors from several domains remained in the models, such as individual characteristics, physiological traits, consumption habits, and regular activities. These factors are sufficiently powerful to influence working memory decline when they jointly interact, as in everyday living.  相似文献   
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This observational study aimed to establishing a relationship between lipid peroxidation and endometriosis in women undergoing controlled ovarian hyperstimulation. A total of 79 women were divided into two groups: (i) controls (tubal or male factor); and (ii) endometriosis (stages III/IV). The endometriosis diagnosis was confirmed by videolaparoscopy and the controlled ovarian stimulation protocol was similar to all patients. Follicular fluid (FF) lipid peroxidation levels were determined through the quantification of malondialdehyde. Statistical analysis was performed using parametric and non-parametric tests, logistic regression was performed to estimate the chance of achieving a pregnancy in each group and a moving average was calculated for the endometriosis group. Peroxidation levels in the endometriosis group were significantly higher when compared to controls. The moving average showed a decrease of MDA levels in the endometriosis group with increasing female age. Moreover, women with endometriosis who were under 33 years of age were 4.3 times more likely to achieve a pregnancy than women above that age. In conclusion, endometriosis is associated with increased FF oxidative stress (OS) in patients undergoing in vitro fertilization (IVF). Also, increasing age is associated with a decrease in severity of the oxidative status, but a decreased chance of pregnancy.  相似文献   
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Quantitative data on branching patterns of the human cerebral arterial tree are lacking in the 1.0–0.1 mm radius range. We aimed to collect quantitative data in this range, and to study if the cerebral artery tree complies with the principle of minimal work (Law of Murray). To enable easy quantification of branching patterns a semi-automatic method was employed to measure 1,294 bifurcations and 2,031 segments on 7 T-MRI scans of two corrosion casts embedded in a gel. Additionally, to measure segments with a radius smaller than 0.1 mm, 9.4 T-MRI was used on a small cast section to characterize 1,147 bifurcations and 1,150 segments. Besides MRI, traditional methods were employed. Seven hundred thirty-three bifurcations were manually measured on a corrosion cast and 1,808 bifurcations and 1,799 segment lengths were manually measured on a fresh dissected cerebral arterial tree. Data showed a large variation in branching pattern parameters (asymmetry-ratio, area-ratio, length-radius-ratio, tapering). Part of the variation may be explained by the variation in measurement techniques, number of measurements and location of measurement in the vascular tree. This study confirms that the cerebral arterial tree complies with the principle of minimum work. These data are essential in the future development of more accurate mathematical blood flow models. Anat Rec, 302:1434–1446, 2019. © 2018 The Authors. The Anatomical Record published by Wiley Periodicals, Inc. on behalf of American Association of Anatomists.  相似文献   
67.
Helicobacter pylori(H.pylori)has been found in the oral cavity and stomach,and its infection is one of the most frequent worldwide.We reviewed the literature and conducted a Topic Highlight,which identified studies reporting an association between H.pylori-infection in the oral cavity and H.pylori-positive stomach bacterium.This work was designed to determine whether H.pylori is the etiologic agent in periodontal disease,recurrent aphthous stomatitis(RAS),squamous cell carcinoma,burning and halitosis.Record selection focused on the highest quality studies and meta-analyses.We selected 48 articles reporting on the association between saliva and plaque and H.pylori-infection.In order to assess periodontal disease data,we included 12 clinical trials and 1 meta-analysis.We evaluated 13 published articles that addressed the potential association with RAS,and 6 with squamous cell carcinoma.Fourteen publications focused on our questions on burning and halitosis.There is a close relation between H.pylori infection in the oral cavity and the stomach.The mouth is the first extra-gastric reservoir.Regarding the role of H.pylori in the etiology of squamous cell carcinoma,no evidence is still available.  相似文献   
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69.
Significant inter-individual variability on the effect of vitamin K to reverse overanticoagulation has been identified. Genetic polymorphisms of the vitamin K epoxide reductase complex subunit 1 (VKORC1) gene might explain in part this variability. The objective of this study was to evaluate the influence of VKORC1 ?1639G>A and 3730G>A polymorphisms on the effect of oral vitamin K supplementation in overanticoagulated patients. We performed an interventional trial of oral vitamin K supplementation in over-anticoagulated outpatients (international normalized ratio [INR] ≥ 4). Subjects received vitamin K (2.5–5.0 mg) according to baseline INR and were genotyped by real time polymerase chain reaction (PCR). INR values were determined at 3, 6, 24 and 72 h after supplementation. We evaluated 33 outpatients, 61 % were males, with a mean age of 62 ± 12 years old. There was a significant decrease in INR values over time for both polymorphisms after oral vitamin K. At 3 h after supplementation, patients carrying the G allele for the ?1639G>A polymorphism had a greater decrease in INR values compared to AA patients (p < 0.05 for difference among groups; p < 0.001 for time variation; p = 0.001 for time × group interaction), with differences of ?1.01 for GG versus AA (p = 0.003) and ?0.84 for GA versus AA (p = 0.024). Mean INR value at 24 h was 1.9 ± 0.6 and at 72 h was 2.1 ± 0.7, with no differences among genotypes. No significant interaction was identified between the 3730G>A polymorphism and vitamin K supplementation. Our study indicated that the VKORC1 ?1639G>A polymorphism plays a role in the response to acute vitamin K supplementation in over-anticoagulated patients, with faster decrease of INR value in patients carrying the G allele.  相似文献   
70.
Adequate prenatal care provides an opportunity for counseling and reducing the complications associated with pregnancy and delivery. Our objective was to describe the demographic, behavioral, and clinical profile of the pregnant women hospitalized at public maternity hospitals and to identify factors associated with six or more prenatal consultations in Vitória, Brazil. A cross-sectional study of 1,380 women was conducted in public maternity hospitals in Vitória, Brazil. Sixty-seven percent of participants had ≥6 prenatal consultations. Reasons for hospitalization were vaginal delivery (55.7%), cesarean section (32.9%), clinical treatment (7.7%), and abortion/miscarriage (3.7%). Having ≥9 years of schooling (odds ratio, OR = 1.8; 95% confidence interval, CI: 1.1–3.1), being married (OR = 1.9; 95% CI: 1.2–2.9) and delivering at term (OR = 3.6; 95% CI: 1.6–8.2) were significantly independently associated with having ≥6 prenatal consultations. Although higher education, being married, and delivering at term were associated with ≥6 prenatal consultations in this population, the high rate of Cesarean sections demonstrates the need for ongoing educative strategies among health professionals.  相似文献   
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