146 research outputs found

    The vegetation of Swartboschkloof, Jonkershoek, Cape Province, South Africa

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    Bibliography: leaves 111-117.Swartboschkloof forms part of the Jonkershoek catchment complex at the headwaters of the Eerste River, Cape Province, South Africa. It has been selected for multi-disciplinary studies of Mountain Fynbos vegetation. The study area has a mainly equatorial aspect (north-facing) and receives an average of 1600 mm rain per annum, mainly in winter. Temperatures do not reach extremes. Winds blow mainly from the south-east, increasing in strength in summer. North-west winds blow intermittently in winter, bringing rain. The altitude of Swartboschkloof ranges between 285 m and 1200 m and the soils are derived from quartzitic Table Mountain Sandstone and porphyritic Cape Granite. Using the Braun-Blanquet phytosociological method, vegetation and environmental data were collected at 201 relevĂŠs throughout the study area; 101 of these relev~s are correlated with a survey of soils of part of the same area. Sixteen fynbos communities, grouped into three groups and five forest communities, grouped into two groups, have been identified. The data of a previous study by Werger, Kruger and Taylor (1972) have been interpreted in the context of this study. A map of the plant communities has been drawn and an attempt has been made to explain the distribution of the communities in terms of environmental factors. There is a strong link between the vegetation and soil geology but application of a method such as principal components analysis would be necessary to explain the relationship clearly

    Normalizing glycosphingolipids restores function in CD4+ T cells from lupus patients

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    Patients with the autoimmune rheumatic disease systemic lupus erythematosus (SLE) have multiple defects in lymphocyte signaling and function that contribute to disease pathogenesis. Such defects could be attributed to alterations in metabolic processes, including abnormal control of lipid biosynthesis pathways. Here, we reveal that CD4+ T cells from SLE patients displayed an altered profile of lipid raft–associated glycosphingolipids (GSLs) compared with that of healthy controls. In particular, lactosylceramide, globotriaosylceramide (Gb3), and monosialotetrahexosylganglioside (GM1) levels were markedly increased. Elevated GSLs in SLE patients were associated with increased expression of liver X receptor β (LXRβ), a nuclear receptor that controls cellular lipid metabolism and trafficking and influences acquired immune responses. Stimulation of CD4+ T cells isolated from healthy donors with synthetic and endogenous LXR agonists promoted GSL expression, which was blocked by an LXR antagonist. Increased GSL expression in CD4+ T cells was associated with intracellular accumulation and accelerated trafficking of GSL, reminiscent of cells from patients with glycolipid storage diseases. Inhibition of GSL biosynthesis in vitro with a clinically approved inhibitor (N-butyldeoxynojirimycin) normalized GSL metabolism, corrected CD4+ T cell signaling and functional defects, and decreased anti-dsDNA antibody production by autologous B cells in SLE patients. Our data demonstrate that lipid metabolism defects contribute to SLE pathogenesis and suggest that targeting GSL biosynthesis restores T cell function in SLE

    DAS28(3)CRP is a reliable measure of disease activity in pregnant women with rheumatoid arthritis

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    OBJECTIVES: The disease activity of rheumatoid arthritis (RA) in pregnancy is most commonly assessed with the modified Disease Activity Score (DAS)-28, the DAS28(3)CRP. However, the performance of the DAS28(3)CRP in pregnancy has not been compared to musculoskeletal ultrasound (MSK-US) as a gold standard. We performed a prospective pilot study to test the hypothesis that pregnancy-related factors limit the reliability of the DAS28(3)CRP. METHODS: Pregnant women with RA were recruited from an Obstetric Rheumatology clinic and assessed during pregnancy (second (T2) and third (T3) trimesters) and postpartum with DAS28(3)CRP and MSK-US scores, with quantification of power Doppler (PD) signal in small joints (hands and feet). Age-matched non-pregnant women with RA underwent equivalent assessments. PD scores were calculated as mean scores of all joints scanned. RESULTS: We recruited 27 pregnant and 20 non-pregnant women with RA. DAS28(3)CRP was sensitive and specific for active RA in pregnancy and postpartum as defined by positive PD signal, but not in non-pregnancy. There were significant correlations between DAS28(3)CRP and PD scores throughout pregnancy (T2, r=0.82 (95% CI [0.42, 0.95], p<0.01); T3, r=0.68 (95% CI [0.38, 0.86], p<0.01)) and postpartum, r=0.84 (95% CI [0.60, 0.94], p<0.01), while this correlation in non-pregnancy was weaker (r=0.47 (95% CI [0, 0.77], p<0.05). CONCLUSIONS: This pilot study found that DAS28(3)CRP is a reliable measure of disease activity in pregnant women with RA. Based on these data, pregnancy does not appear to confound clinical evaluation of the tender and/or swollen joint counts

    Sensitization to gliadin induces moderate enteropathy and insulitis in nonobese diabetic-DQ8 mice

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    Celiac disease (CD) is frequently diagnosed in patients with type 1 diabetes (T1D), and T1D patients can exhibit Abs against tissue transglutaminase, the auto-antigen in CD. Thus, gliadin, the trigger in CD, has been suggested to have a role in T1D pathogenesis. The objective of this study was to investigate whether gliadin contributes to enteropathy and insulitis in NOD-DQ8 mice, an animal model that does not spontaneously develop T1D. Gliadin-sensitized NOD-DQ8 mice developed moderate enteropathy, intraepithelial lymphocytosis, and barrier dysfunction, but not insulitis. Administration of anti-CD25 mAbs before gliadin-sensitization induced partial depletion of CD25+Foxp3+ T cells and led to severe insulitis, but did not exacerbate mucosal dysfunction. CD4+T cells isolated from pancreatic lymph nodes of mice that developed insulitis showed increased proliferation and proinflammatory cytokines after incubation with gliadin but not with BSA. CD4+ T cells isolated from nonsensitized controls did not response to gliadin or BSA. In conclusion, gliadin sensitization induced moderate enteropathy in NOD-DQ8 mice. However, insulitis development required gliadin-sensitization and partial systemic depletion of CD25+Foxp3+ T cells. This humanized murine model provides a mechanistic link to explain how the mucosal intolerance to a dietary protein can lead to insulitis in the presence of partial regulatory T cell deficiency.Facultad de Ciencias Exacta

    The Period Changes of the Cepheid RT Aurigae

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    Observations of the light curve for the 3.7-day Cepheid RT Aur both before and since 1980 indicate that the variable is undergoing an overall period increase, amounting to +0.082 +-0.012 s/yr, rather than a period decrease, as implied by all observations prior to 1980. Superposed on the star's O-C variations is a sinusoidal trend that cannot be attributed to random fluctuations in pulsation period. Rather, it appears to arise from light travel time effects in a binary system. The derived orbital period for the system is P = 26,429 +-89 days (72.36 +-0.24 years). The inferred orbital parameters from the O-C residuals differ from those indicated by existing radial velocity data. The latter imply the most reasonable results, namely a1 sin i = 9.09 (+-1.81) x 10^8 km and a minimum secondary mass of M2 = 1.15 +-0.25 Msun. Continued monitoring of the brightness and radial velocity changes in the Cepheid are necessary to confirm the long-term trend and to provide data for a proper spectroscopic solution to the orbit.Comment: Accepted for publication in PASP (November 2007

    De novo mutations in EIF2B1 affecting eIF2 signaling cause neonatal/early onset diabetes and transient hepatic dysfunction

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    Permanent neonatal diabetes is caused by reduced β-cell number or impaired β-cell function. Understanding the genetic basis of this disorder highlights fundamental β-cell mechanisms. We performed trio genome sequencing for 44 permanent neonatal diabetes patients and their unaffected parents to identify causative de novo variants. Replication studies were performed in 188 patients diagnosed with diabetes before 2 years of age without a genetic diagnosis. EIF2B1 (encoding the eIF2B complex α subunit) was the only gene with novel de novo variants (all missense) in at least three patients. Replication studies identified 2 further patients with de novo EIF2B1 variants. In addition to diabetes, 4/5 patients had hepatitis-like episodes in childhood. The EIF2B1 de novo mutations were found to map to the same protein surface. We propose that these variants render the eIF2B complex insensitive to eIF2 phosphorylation which occurs under stress conditions and triggers expression of stress-response genes. Failure of eIF2B to sense eIF2 phosphorylation likely leads to unregulated unfolded protein response and cell death. Our results establish de novo EIF2B1 mutations as a novel cause of permanent diabetes and liver dysfunction. These findings confirm the importance of cell stress regulation for β-cells and highlight EIF2B1’s fundamental role within this pathway.Includes NIHR and Wellcome Trust. Wellcome Trust 200848/Z/16/

    Prospectus, February 22, 1984

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    MILLER SAYS TAX ABATEMENT NOT EQUITABLE FOR OTHER COUNTIES: REQUEST FOR TAX ABATEMENT DENIED BY PARKLAND BOARD; News Digest; Mayor Markland concered about area landfill issue; Meet the Prospectus Staff; PC Happenings: Professor to speak at Parkland, Testing for self knowledge, Computer workshop offered at Parkland, EMT workshop at Parkland; Which is better juvenile and pointless; Letter; Sonja Williams--views on Nicaragua; Yaxley scholarship; In the Library-- PS section; \u27I was only gone a minute\u27; Contraceptives--become aware of your choices; Internships produce anxieties; Did You Know...; Archaeology trip a success; Alabama shines at Assembly Hall; Creative Corner...Especially for you!!: Fleeting Moments, Untitled, Reflections and contemplations, Down, down, down, The Talkers , My Grandfather, Windows From the Soul, Realities, Banging heads on the floor with you...; Moore of the same; \u27Alabama\u27 succeeds at local concert; \u27I Write Your Name\u27 Carroll album released; Hitchcock\u27s classic revisited in the film \u27Vertigo\u27; Classifieds; More than tickets...; I.M.; Movie Magazine in next issue; Men\u27s Basketball season 20-11; Men\u27s track team places third; Parkland to host basket ball tournament; Women\u27s track team 2nd in region; Fitness Center to openhttps://spark.parkland.edu/prospectus_1984/1030/thumbnail.jp

    Prospectus, February 15, 1984

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    ELECTION RESULTS; News Digest; Blacks added to local history; Letter from the editor; Letter to the editor; Letter to the editor; PC Happenings: Real estate review workshop, Lifelong Learners to meet, Story shop stimulates young writers, EMT assessment workshop offered; Gameroom damage--why!!; Student award; Letter to the editor; Roberts nominated; Book Review: Making College Pay Off ; Reflections and contemplations; Student needs witness; Division chairman believes in Parkland; \u27Images\u27 needs you; Dodd explains his position on Miller; Did You Know...; Coach encouraged at team\u27s success; Wheelchair games postponed; Fewer students at Parkland; Bushman and Gunter; Survival trip taken; \u27Shadows Beyond the Benefit....\u27 entices thinking; Davis says farewell; Eclectic collection of art; Creative Corner...Especially for you!!: Freedom, To God, A Worn-out photograph, Memories, Clouds, The Spreading Flame, Why, Haunting Beauty, Lost Love, The Wheel of Fortune, What Is the Vocal?, The Petals of Marie, Unknown, No Defeat, A Tribute to Fallen Hero; John Watching ; King led the way for blacks in the 1960\u27s; Anti-discrimination pledge signed; Rosa Parks remembered; Black colleges pitch into nationwide crisis; Play review; Dream becomes day-to-day reality; Increase Awareness of Financial Aid Available; Colored Girls stresses stereotyping; Yaxley scholarship; Black collection extensive; \u27Operation Snowball\u27 helps teens help themselves; In the Library-- P Section; Question: Do you think we will ever attain world peace?; Classifieds; \u27Four Seasons\u27 blast of fresh air; Campus Paperback Bestsellers; New & Recommended; Another political album for U2 with \u27Under a Blood Red Sky\u27; New Dorothy after 45 years; Institute shows rare independent British films; Film festival schedule; MTV--a hit that\u27s here to stay; Utopia reminds us that it is 1984; Silkwood should be seen by all; Nicaragua, a problem the U.S. should study now; Trout remembers when; I.M. News; Wulf recalls coaching days; Carper recalls Parkland; Martin wins triple jump at meet; Composite athletic schedule; Competition aids inequalityhttps://spark.parkland.edu/prospectus_1984/1031/thumbnail.jp
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