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The effects of an immersion bilingual mathematics institute on the achievement of seventh grade Mexican-American students
The purpose of this study was to determine the extent to which an Immersion Bilingual Mathematics Institute (IBMI) can affect the mathematics achievement of entering seventh grade students of Mexican-American heritage. Mathematics achievement was defined as
mathematics skills measured by the Mathematics Computation and Mathematics Concepts and Applications tests of the Comprehensive Test of Basic Skills (CTBS) battery. A four-week, 80-hour supplementary mathematics institute was designed to increase computation skills in addition, subtraction, multiplication, and division of fractions, decimals and mixed numbers and in solving word problems requiring these skills. The IBMI curriculum included lessons requiring the use of manipulative materials such as measuring instruments to solve
mathematics problems perceived to be relevant to the students. Bilingual mathematics teachers rotated daily among three subgroups of 8 to 12 students classified according to English language ability. Instruction was
characterized by teacher direction, high energy instruction, positive reinforcement and rapid drill sessions. A modified Pretest-Posttest Control Group design was used. Incoming Mexican-American seventh grade
volunteers from five Orange, California schools were blocked by sex and CTBS reading scores and randomly assigned into 30-student treatment and control groups. A second control consisted of 40 similar seventh grade
Anglo-American students. One level of the CTBS battery was administered as a pretest in May, 1981. A higher level of the CTBS served as posttests in late August at the end of the IBMI and again six months later. The Institute was conducted in El Modena High School mathematics classrooms in August, 1981. Significant (p < .05) gains in mathematics achievement were made by the treatment group on tests administered at the end of the IBMI. These gains were positive, but non-significant when compared to the two
control groups six months later. Data obtained for the study confirmed a mathematics achievement disparity between Mexican-American and Anglo-American students in Orange schools comparable to data reported for other regions of the Southwest. The researcher concludes that an IBMI designed to
meet the linguistic and cultural preferences of Mexican American students has a short-term effect in significantly increasing their mathematics skills and in reducing the mathematics achievement disparity, but that
these gains are not significant six months later
Submacular Choroid Thickness Increases During Long-Duration Spaceflight
The Spaceflight Associated Neuro-ocular Syndrome (SANS) is characterized by the development of optic disc edema, choroidal folds, cotton-wool spots, globe flattening, and/or refractive error changes greater than or equal to 0.75D during long-duration spaceflight to the International Space Station (ISS). It is hypothesized that these findings result from the headward fluid shift that occurs due to weightlessness. We can induce a headward fluid shift on Earth using positional changes and on ISS due to weightlessness. Lower-body negative pressure (LBNP) is used to reverse the headward fluid shift by drawing fluid into the lower body and can be used on Earth and on ISS
Changes in the Optic Nerve Head and Choroid Over 1 Year of Spaceflight
Importance: While 6-month data are available regarding spaceflight-associated neuro-ocular syndrome, manned missions for 1 year and beyond are planned, warranting evaluation for spaceflight-associated neuro-ocular syndrome beyond 6 months.
Objective: To determine if the manifestation of spaceflight-associated neuro-ocular syndrome worsens during International Space Station missions exceeding the present 4- to 6-month duration.
Design, Setting, and Participants: The One-Year Mission Study used quantitative imaging modalities to investigate changes in ocular structure in 2 crew members who completed a 1-year-long spaceflight mission. This study investigated the ocular structure of crew members before, during, and after their mission on the International Space Station. Two crew members participated in this study from March 2015 to September 2016. Analysis began in March 2015 and ended in May 2020.
Exposures: Crew members were tested before, during, and up to 1 year after spaceflight.
Main Outcomes and Measures: This study compares ocular changes (peripapillary retinal edema, axial length, anterior chamber depth, and refraction) in two 1-year spaceflight mission crew members with cohort crew members from a 6-month mission (n = 11). Minimum rim width (the shortest distance between Bruch membrane opening and the internal limiting membrane) and peripapillary total retinal thickness were measured using optical coherence tomography.
Results: Both crew members were men. Minimum rim width and total retinal thickness increased in both participants throughout the duration of spaceflight exposure to the maximal observed change from preflight (minimum rim width: participant 1, 561 [+149 from preflight] ÎĽm at flight day 270; participant 2, 539 [+56 from preflight] ÎĽm at flight day 270; total retinal thickness: participant 1, 547 [+135 from preflight] ÎĽm at flight day 90; participant 2, 528 [+45 from preflight] ÎĽm at flight day 210). Changes in peripapillary choroid engorgement, axial length, and anterior chamber depth appeared similar between the 1-year mission participants and a 6-month mission cohort.
Conclusions and Relevance: This report documents the late development of mild optic disc edema in 1 crew member and the progressive development of choroidal folds and optic disc edema in another crew member over the duration of 1 year in low Earth orbit aboard the International Space Station. Previous reports characterized the ocular risk associated with 4 to 6 months of spaceflight. As future spaceflight missions are planned to increase in duration and extend beyond low Earth orbit, further observation of astronaut ocular health on spaceflight missions longer than 6 months in duration may be warranted
Caveolin-1 protects B6129 mice against Helicobacter pylori gastritis.
Caveolin-1 (Cav1) is a scaffold protein and pathogen receptor in the mucosa of the gastrointestinal tract. Chronic infection of gastric epithelial cells by Helicobacter pylori (H. pylori) is a major risk factor for human gastric cancer (GC) where Cav1 is frequently down-regulated. However, the function of Cav1 in H. pylori infection and pathogenesis of GC remained unknown. We show here that Cav1-deficient mice, infected for 11 months with the CagA-delivery deficient H. pylori strain SS1, developed more severe gastritis and tissue damage, including loss of parietal cells and foveolar hyperplasia, and displayed lower colonisation of the gastric mucosa than wild-type B6129 littermates. Cav1-null mice showed enhanced infiltration of macrophages and B-cells and secretion of chemokines (RANTES) but had reduced levels of CD25+ regulatory T-cells. Cav1-deficient human GC cells (AGS), infected with the CagA-delivery proficient H. pylori strain G27, were more sensitive to CagA-related cytoskeletal stress morphologies ("humming bird") compared to AGS cells stably transfected with Cav1 (AGS/Cav1). Infection of AGS/Cav1 cells triggered the recruitment of p120 RhoGTPase-activating protein/deleted in liver cancer-1 (p120RhoGAP/DLC1) to Cav1 and counteracted CagA-induced cytoskeletal rearrangements. In human GC cell lines (MKN45, N87) and mouse stomach tissue, H. pylori down-regulated endogenous expression of Cav1 independently of CagA. Mechanistically, H. pylori activated sterol-responsive element-binding protein-1 (SREBP1) to repress transcription of the human Cav1 gene from sterol-responsive elements (SREs) in the proximal Cav1 promoter. These data suggested a protective role of Cav1 against H. pylori-induced inflammation and tissue damage. We propose that H. pylori exploits down-regulation of Cav1 to subvert the host's immune response and to promote signalling of its virulence factors in host cells
Liver cancer cell lines distinctly mimic the metabolic gene expression pattern of the corresponding human tumours
Background: Although metabolism is profoundly altered in human liver cancer, the extent to which experimental models, e.g. cell lines, mimic those alterations is unresolved. Here, we aimed to determine the resemblance of hepatocellular carcinoma (HCC) cell lines to human liver tumours, specifically in the expression of deregulated metabolic targets in clinical tissue samples.
Methods: We compared the overall gene expression profile of poorly-differentiated (HLE, HLF, SNU-449) to well-differentiated (HUH7, HEPG2, HEP3B) HCC cell lines in three publicly available microarray datasets. Three thousand and eighty-five differentially expressed genes in ≥2 datasets (P < 0.05) were used for pathway enrichment and gene ontology (GO) analyses. Further, we compared the topmost gene expression, pathways, and GO from poorly differentiated cell lines to the pattern from four human HCC datasets (623 tumour tissues). In well- versus poorly differentiated cell lines, and in representative models HLE and HUH7 cells, we specifically assessed the expression pattern of 634 consistently deregulated metabolic genes in human HCC. These data were complemented by quantitative PCR, proteomics, metabolomics and assessment of response to thirteen metabolism-targeting compounds in HLE versus HUH7 cells.
Results: We found that poorly-differentiated HCC cells display upregulated MAPK/RAS/NFkB signaling, focal adhesion, and downregulated complement/coagulation cascade, PPAR-signaling, among pathway alterations seen in clinical tumour datasets. In HLE cells, 148 downregulated metabolic genes in liver tumours also showed low gene/protein expression – notably in fatty acid β-oxidation (e.g. ACAA1/2, ACADSB, HADH), urea cycle (e.g. CPS1, ARG1, ASL), molecule transport (e.g. SLC2A2, SLC7A1, SLC25A15/20), and amino acid metabolism (e.g. PHGDH, PSAT1, GOT1, GLUD1). In contrast, HUH7 cells showed a higher expression of 98 metabolic targets upregulated in tumours (e.g. HK2, PKM, PSPH, GLUL, ASNS, and fatty acid synthesis enzymes ACLY, FASN). Metabolomics revealed that the genomic portrait of HLE cells co-exist with profound reliance on glutamine to fuel tricarboxylic acid cycle, whereas HUH7 cells use both glucose and glutamine. Targeting glutamine pathway selectively suppressed the proliferation of HLE cells.
Conclusions: We report a yet unappreciated distinct expression pattern of clinically-relevant metabolic genes in HCC cell lines, which could enable the identification and therapeutic targeting of metabolic vulnerabilities at various liver cancer stages.
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CORRECTION
Published online 2.11.2018 in Journal of Experimental & Clinical Cancer Research, 37 (2018), Nr. 267; DOI: https://doi.org/10.1186/s13046-018-0939-4. In the publication of this article, there was an error in Fig. 5b. This has been updated in the original article on BioMed Central's website. The authors declare that the correction does not change the results or conclusions of this paper
Correction to: Liver cancer cell lines distinctly mimic the metabolic gene expression pattern of the corresponding human tumours
Table S5. Complete list of downregulated HMGs concordantly low in the p.d. cells (part of Fig. 2c). (DOCX 14 kb
Smoke gets in your eyes: re-reading gender in the "nostalgia film"
Upon its release, American Graffiti (George Lucas, 1973) was much admired by critics and audiences alike. Yet, in subsequent years, the film became known for its supposed “flattening of history,” and celebration of patriarchal values. This article demonstrates that such a judgement owes much to Fredric Jameson’s historically contingent work on postmodernism, which argues that American Graffiti constitutes the paradigmatic nostalgia film. In contrast, using close textual analysis, I demonstrate that American Graffiti provides a more complex construction of the past, and of gender, than has hitherto been acknowledged. Far from blindly idealising the early 1960s, the film interrogates the processes through which the period and its gender relations come to be idealised. This article has consequences not only for our understanding of Lucas’ seminal film, but also for the American New Wave, and the “nostalgia” text
Ursolic Acid Increases Skeletal Muscle and Brown Fat and Decreases Diet-Induced Obesity, Glucose Intolerance and Fatty Liver Disease
Skeletal muscle Akt activity stimulates muscle growth and imparts resistance to obesity, glucose intolerance and fatty liver disease. We recently found that ursolic acid increases skeletal muscle Akt activity and stimulates muscle growth in non-obese mice. Here, we tested the hypothesis that ursolic acid might increase skeletal muscle Akt activity in a mouse model of diet-induced obesity. We studied mice that consumed a high fat diet lacking or containing ursolic acid. In skeletal muscle, ursolic acid increased Akt activity, as well as downstream mRNAs that promote glucose utilization (hexokinase-II), blood vessel recruitment (Vegfa) and autocrine/paracrine IGF-I signaling (Igf1). As a result, ursolic acid increased skeletal muscle mass, fast and slow muscle fiber size, grip strength and exercise capacity. Interestingly, ursolic acid also increased brown fat, a tissue that shares developmental origins with skeletal muscle. Consistent with increased skeletal muscle and brown fat, ursolic acid increased energy expenditure, leading to reduced obesity, improved glucose tolerance and decreased hepatic steatosis. These data support a model in which ursolic acid reduces obesity, glucose intolerance and fatty liver disease by increasing skeletal muscle and brown fat, and suggest ursolic acid as a potential therapeutic approach for obesity and obesity-related illness
Early Adverse Events, HPA Activity and Rostral Anterior Cingulate Volume in MDD
Prior studies have independently reported associations between major depressive disorder (MDD), elevated cortisol concentrations, early adverse events and region-specific decreases in grey matter volume, but the relationships among these variables are unclear. In the present study, we sought to evaluate the relationships between grey matter volume, early adverse events and cortisol levels in MDD.Grey matter volume was compared between 19 controls and 19 individuals with MDD using voxel-based morphometry. A history of early adverse events was assessed using the Childhood Trauma Questionnaire. Subjects also provided salivary cortisol samples. Depressed patients showed decreased grey matter volume in the rostral ACC as compared to controls. Rostral ACC volume was inversely correlated with both cortisol and early adverse events.These findings suggest a key relationship between ACC morphology, a history of early adverse events and circulating cortisol in the pathophysiology of MDD
Degradation of GSPT1 causes TP53-independent cell death in leukemia whilst sparing normal hematopoietic stem cells
Targeted protein degradation is a rapidly advancing and expanding therapeutic approach. Drugs that degrade GSPT1 via the CRL4CRBN ubiquitin ligase are a new class of cancer therapy in active clinical development with evidence of activity against acute myeloid leukemia in early phase trials. However, other than activation of the integrated stress response, the downstream effects of GSPT1 degradation leading to cell death are largely undefined, and no murine models are available to study these agents. We identified the domains of GSPT1 essential for cell survival and show that GSPT1 degradation leads to impaired translation termination, activation of the integrated stress response pathway, and TP53-independent cell death. CRISPR-Cas9 screens implicated decreased translation initiation as protective to GSPT1 degradation, suggesting that cells with higher levels of translation are more susceptible to GSPT1 degradation. We defined two Crbn amino acids that prevent Gspt1 degradation in mice, generated a knock-in mouse with alteration of these residues, and demonstrated the efficacy of GSPT1-degrading drugs in vivo with relative sparing of numbers and function of long-term hematopoietic stem cells. Our results provide a mechanistic basis for the use of GSPT1 degraders for the treatment of cancer, including TP53-mutant AML
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