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951.
Epidemiological studies have shown that early first pregnancy is associated with a life-long reduction in breast cancer risk. The terminal differentiation associated with pregnancy and lactation has been proposed as a mechanism underlying the protective effect of pregnancy. We report that treatment of rats with ICI 182,780 (ICI) caused a marked reduction in epithelial cells and Ki-67 labelling index as compared to controls and testosterone enanthate-treated (TE) mammary glands. TE increased the Ki-67 labelling index, stimulated lobuloalveolar and ductal growth, as well as the secretory activity of acinar cells. Co-administration of TE and ICI resulted in a reduction in Ki-67 labelling index. Mammary epithelial cells became differentiated, resembling that observed at the end of pregnancy and during lactation as indicated by marked increase in secretory activity, lipid accumulation and presence of basal nuclei. The expression of differentiation markers such as whey acidic protein, mammary derived growth inhibitor, alpha-casein and beta-casein was detected only in TE plus ICI treated mammary tissues. Unlike TE, ICI caused a significant reduction in DMBA-induced tumour incidence, number of tumour bearing and tumour size. Tumour incidence was reduced to 8% when both ICI and TE were co-administered. Our data provide the novel molecular interactions between the estrogen and androgen in regulation of mammary growth and differentiation. These observations may give insight into novel actions of ICI and TE on breast differentiation and protection against carcinogenesis which may be useful in designing novel strategies for cancer prevention and/or treatment based on maximizing mammary epithelial cell differentiation. 相似文献
952.
R A Wascher P J Bostick K T Huynh R Turner K Qi A E Giuliano D S Hoon 《British journal of cancer》2001,85(9):1340-1346
The detection of occult metastatic breast cancer cells by RT-PCR is limited by the poor specificity of most tumour mRNA markers. MAGE-A3 is a highly specific tumour mRNA marker that is not expressed in non-cancer cells. This study assesses MAGE-A3 mRNA as a molecular marker for the detection of tumour cells in the sentinel lymph nodes (SLN) of breast cancer patients. Serial frozen sections of SLN (n = 121) were obtained from 77 AJCC (American Joint Committee on Cancer) Stage I-IIIA breast cancer patients. MAGE-A3 mRNA analysis of SLN was performed by RT-PCR and Southern blot analysis. Tumour cells were detected in 48 of 121 (40%) SLN from 77 patients by H&E or IHC staining, and 35 of 77 (45%) patients, overall, had histopathologically (H&E and/or IHC) positive SLN. Among histopathologically negative SLN, 28 of 73 (38%) SLN were MAGE-A3 mRNA positive by RT-PCR. Overall, 41 of 77 (53%) patients and 50 of 121 (41%) SLN were positive for MAGE-A3. MAGE-A3 mRNA expression in the SLN occurred more frequently with infiltrating lobular carcinoma (P < 0.001) than with infiltrating ductal carcinoma, adding further evidence of possible phenotypic differences between these 2 subtypes of breast cancer. Due to its high specificity, MAGE-A3 mRNA is a potentially useful marker for detecting breast cancer cells in the SLN. One half of breast tumours expressed MAGE-A3 mRNA, which has important potential implications for antigen-specific targeted immunotherapy. 相似文献
953.
H van Thien M T Ackermans E Dekker V O Thanh Chien T Le E Endert P A Kager J A Romijn H P Sauerwein 《QJM : monthly journal of the Association of Physicians》2001,94(12):709-715
Hypoglycaemia is an important complication in severe malaria, ascribed to an inhibition of gluconeogenesis. However, the only data available suggested that in severe malaria, total glucose production is increased. We measured glucose production and gluconeogenesis after an overnight fast in all seven patients with cerebral malaria (CM) consecutively admitted to Bao Loc General hospital over a 2-year period, and in six healthy sex- and age-matched controls. Glucose production was measured by infusion of [6,6-(2)H(2)]glucose and the contribution of gluconeogenesis by oral ingestion of (2)H(2)O. Compared to controls, plasma glucose concentration was 42% higher in CM patients (p=0.004), and glucose production was doubled (p=0.003). Gluconeogenesis contributed 100% of the total glucose in CM patients but only 58% in controls (p=0.003). The plasma concentrations of the substrates for gluconeogenesis and the glucoregulatory hormones were not different between patients and controls, except for an increase in lactate and cortisol in the patients. Cerebral malaria is associated with increases rather than decreases in plasma glucose, glucose production and gluconeogenesis, and there is no contribution of glycogenolysis to glucose production. Factors other than malaria per se are involved in the pathogenesis of hypoglycaemia associated with CM. 相似文献
954.
Parenteral nutrition (PN) provides support for patients lacking sufficient intestinal absorption of nutrients. Historically, the need for trace element (TE) supplementation was poorly appreciated, and multi-TE products were not initially subjected to rigorous oversight by the United States Food and Drug Administration (FDA). Subsequently, the American Society for Parenteral and Enteral Nutrition (ASPEN) issued dosage recommendations for PN, which are updated periodically. The FDA has implemented review and approval processes to ensure access to safer and more effective TE products. The development of a multi-TE product meeting ASPEN recommendations and FDA requirements is the result of a partnership between the FDA, industry, and clinicians with expertise in PN. This article examines the rationale for the development of TRALEMENT® (Trace Elements Injection 4*) and the FDA’s rigorous requirements leading to its review and approval. This combination product contains copper, manganese, selenium, and zinc and is indicated for use in adults and pediatric patients weighing ≥10 kg. Comprehensive management of PN therapy requires consideration of many factors when prescribing, reviewing, preparing, and administering PN, as well as monitoring the nutritional status of patients receiving PN. Understanding patients’ TE requirements and incorporating them into PN is an important part of contemporary PN therapy. 相似文献
955.
956.
Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations. Results on the diffusion/conduction process show that these nanocrystalline samples are characterized with higher activation energies as compared to previous theoretical studies, but closer to experiment. Such a performance can be attributed to the larger atomic density at the ∑3(111) grain boundary regions within the nanocrystals. Despite a minor deterioration of transport properties of the mixed cation Li2NaOX and Na2LiOX samples, these halogeno-alkali oxides can also be considered as good inorganic solid electrolytes in both Li- and Na-ion batteries.Transport properties of the halogeno-alkali oxides A3OX (A = Li, Na, X = Cl, Br) nanocrystalline samples with the presence of ∑3(111) grain boundaries were computed using large-scale molecular dynamic simulations. 相似文献
957.
Takayuki Fujii Masao Hagihara Keiko Mitamura Shiori Nakashima Shin Ohara Tomoyuki Uchida Morihiro Inoue Moe Okuda Atsuhiro Yasuhara Jurika Murakami Calvin Duong Kiyoko Iwatsuki-Horimoto Seiya Yamayoshi Yoshihiro Kawaoka 《Internal medicine (Tokyo, Japan)》2022,61(11):1681
Objective Coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has spread globally. Although the relationship between anti-SARS-CoV-2 immunoglobulin G (IgG) antibodies and COVID-19 severity has been reported, information is lacking regarding the seropositivity of patients with particular types of diseases, including hematological diseases. Methods In this single-center, retrospective study, we compared SARS-CoV-2 IgG positivity between patients with hematological diseases and those with non-hematological diseases. Results In total, 77 adult COVID-19 patients were enrolled. Of these, 30 had hematological disorders, and 47 had non-hematological disorders. The IgG antibody against the receptor-binding domain of the spike protein was detected less frequently in patients with hematological diseases (60.0%) than in those with non-hematological diseases (91.5%; p=0.029). Rituximab use was significantly associated with seronegativity (p=0.010). Conclusion Patients with hematological diseases are less likely to develop anti-SARS-CoV-2 antibodies than those with non-hematological diseases, which may explain the poor outcomes of COVID-19 patients in this high-risk group. 相似文献
958.
Jennifer A. Westwood Geoffrey M. Matthews Jake Shortt David Faulkner Hollie J. Pegram Connie P.M. Duong Marta Chesi P. Leif Bergsagel Leslie L. Sharp Richard D. Huhn Phillip K. Darcy Ricky W. Johnstone Michael H. Kershaw 《Leukemia research》2014
In order to stimulate antigen presentation and T cell activity against cancer, we treated three different tumor models in mice with the monoclonal antibodies anti-CD40 plus anti-CD137 (BiMab). In a subcutaneous transplantable MC38 colon cancer model, there was significant enhancement in the survival of mice following BiMab treatment. Anti-CD40 has shown considerable success against lymphoma in previous studies by other investigators, and we also showed in this study that, in a model of Eμ-Myc lymphoma, there was a statistically significant enhancement of survival of mice following BiMab treatment. Following the success of the BiMab treatment in the previous two models, we wished to determine if it would be successful in a mouse model of multiple myeloma. Firstly, we tested a transplantable model of disease in which multiple myeloma cells derived from Vk*MYC mice were injected intravenously. A minor proportion of anti-CD137 and BiMab treated mice experienced prolongation of life beyond 250 days. Then we tested the therapy in a spontaneously occurring multiple myeloma model, in Vk*MYC transgenic mice. The majority of mice treated survived longer than control mice, although statistical significance was not demonstrated. 相似文献
959.
Nguyen Duy Hung Le Thanh Dung Dang Khanh Huyen Ngo Quang Duy Dong-Van He Nguyen Minh Duc 《International journal of medical sciences》2022,19(7):1110
Background: Prior studies have suggested a number of the subjective visual characteristics that help distinguish between spinal meningiomas and schwannomas on magnetic resonance imaging and computed tomography; however, objective quantification of the signal intensity can be useful information. This study assessed whether quantitative magnetic resonance imaging (MRI) signal intensity (SI) measurements could distinguish intradural-extramedullary schwannomas from meningiomas.Methods: From July 2019 to September 2021, 54 patients with intradural-extramedullary tumors (37 meningiomas and 17 schwannomas) underwent surgery, and tumors were verified pathologically. Defined regions of interest were used to quantify SI values on T1- (T1W) and T2-weighted images (T2W). Receiver operating characteristic curve analysis was used to obtain cutoff values and calculate the area under the curve (AUC), sensitivity (SE), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV).Results: Both Maximum (T2max) and mean (T2mean) T2W SI values demonstrated outstanding (AUC: 0.91) abilities to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T2max and 81.1%, 88.2%, 93.8%, and 68.2% for T2mean. The maximum SI value on contrast-enhanced T1W (T1CEmax) and the T2W tumor: fat SI ratio (rTF) demonstrated acceptable abilities (AUC: 0.73 and 0.79, respectively) to differentiate meningiomas from schwannomas with Se, Sp, PPV, and NPV values of 94.6%, 70.6%, 87.5%, and 85.7%, respectively, for T1CEmax and 81.1%, 88.2%, 93.8%, and 68.2% for rTF.Conclusions: Quantitative SI values (T2max, T2mean, T2min, T1CEmax, rTF) can be used to differentiate intradural-extramedullary schwannomas from meningiomas. 相似文献
960.
Tuyen Van Duong Minh H. Nguyen Chih-Feng Lai Sheng-Chih Chen Kevin Dadaczynski Orkan Okan Cheng-Yu Lin 《Annals of medicine》2022,54(1):2064
BackgroundSchool principals have been reported to have a higher prevalence of burnout and psychological problems than their colleagues. During the pandemic, extra workload and pressure from unprecedented situations potentially cause fear, stress and depression. Therefore, we aimed to explore associated factors of stress, fear of COVID-19 (F-CoV-19S) and depressive symptoms among school principals.MethodsA cross-sectional online survey was conducted in Taiwan from 23 June to 16 July 2021. Data of 413 school principals were collected, including socio-demographic factors, COVID-19-related factors, work-related information, health status, sense of coherence (SoC), health literacy (HL), F-CoV-19S, stress and depression. Multiple linear and logistic regression models were utilized to explore associations.ResultsSchool principals with symptoms like COVID-19 (S-COVID-19-S), or with health-related activity limitations had a higher score of stress (B = 0.92; p = .039) (B = 1.52; p < .001) and a higher depression likelihood (OR = 3.38; p < .001) (OR = 3.06; p < .001), whereas those with a better SoC had a lower stress score (B = −1.39; p < .001) and a lower depression likelihood (OR = 0.76; p = .020). School principals confusing about COVID-19-related information had a higher score of stress (B = 2.47; p < .001) and fear (B = 3.77; p < .001). The longer working time was associated with a higher fear score (B = 1.69; p = .006). Additionally, school principals with a higher HL score had a lower stress score (B = −1.76; p < .001), a lower fear score (B = −1.85; p < .001) and a lower depression likelihood (OR = 0.53; p = .043).ConclusionsHealth-related activity limitations, S-COVID-19-S, COVID-19-related information confusion and longer working hours were positively associated with at least one mental health problem (e.g. stress, fear and depression), whereas better SoC and HL showed the benefits to mitigate fear, stress and depressive symptoms in school principals. Our study provides evidence for appropriate strategies to improve principals’ mental health during the pandemic.
Key messages:
- School principals with health-related activity limitations or with symptoms like COVID-19 were more likely to be stressed and depressed.
- Higher levels of stress and fear were observed in school principals who confused about COVID-19-related information, and who had longer working time than before the pandemic.
- Better sense of coherence and higher health literacy could potentially mitigate the fear, stress and depressive symptoms in school principals.