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81.
Elizabeth du Toit Cari van Schalkwyk Rory Dunbar Karen Jennings Blia Yang David Coetzee Nulda Beyers 《PloS one》2014,9(5)
Background
Few studies have evaluated access to and retention in pre-ART care.Objectives
To evaluate the proportion of People Living With HIV (PLWH) in pre-ART and ART care and factors associated with retention in pre-ART and ART care from a community cohort.Methods
A cross sectional survey was conducted from February – April 2011. Self reported HIV positive, negative or participants of unknown status completed a questionnaire on their HIV testing history, access to pre-ART and retention in pre-ART and ART care.Results
872 randomly selected adults who reported being HIV positive in the ZAMSTAR 2010 prevalence survey were included and revisited. 579 (66%) reconfirmed their positive status and were included in this analysis. 380 (66%) had initiated ART with 357 of these (94%) retained in ART care. 199 (34%) had never initiated ART of whom 186 (93%) accessed pre-ART care, and 86 (43%) were retained in pre-ART care. In a univariable analysis none of the factors analysed were significantly associated with retention in care in the pre-ART group. Due to the high retention in ART care, factors associated with retention in ART care, were not analysed further.Conclusion
Retention in ART care was high; however it was low in pre-ART care. The opportunity exists, if care is better integrated, to engage with clients in primary health care facilities to bring them back to, and retain them in, pre-ART care. 相似文献82.
Christina A. Pacak Peter E. Hammer Allison A. MacKay Rory P. Dowd Kai-Roy Wang Akihiro Masuzawa Bjoern Sill James D. McCully Douglas B. Cowan 《PloS one》2014,9(9)
The purpose of this study was to determine the ability of superparamagnetic iron oxide (SPIO) nanoparticles to function as a long-term tracking label for multi-modal imaging of implanted engineered tissues containing muscle-derived progenitor cells using magnetic resonance imaging (MRI) and X-ray micro-computed tomography (μCT). SPIO-labeled primary myoblasts were embedded in fibrin sealant and imaged to obtain intensity data by MRI or radio-opacity information by μCT. Each imaging modality displayed a detection gradient that matched increasing SPIO concentrations. Labeled cells were then incorporated in fibrin sealant, injected into the atrioventricular groove of rat hearts, and imaged in vivo and ex vivo for up to 1 year. Transplanted cells were identified in intact animals and isolated hearts using both imaging modalities. MRI was better able to detect minuscule amounts of SPIO nanoparticles, while μCT more precisely identified the location of heavily-labeled cells. Histological analyses confirmed that iron oxide particles were confined to viable, skeletal muscle-derived cells in the implant at the expected location based on MRI and μCT. These analyses showed no evidence of phagocytosis of labeled cells by macrophages or release of nanoparticles from transplanted cells. In conclusion, we established that SPIO nanoparticles function as a sensitive and specific long-term label for MRI and μCT, respectively. Our findings will enable investigators interested in regenerative therapies to non-invasively and serially acquire complementary, high-resolution images of transplanted cells for one year using a single label. 相似文献
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85.
Rory Paul Wilson 《Journal of Ornithology》1985,126(1):53-62
Summary Jackass Penguins breed throughout the year but show seasonal preferences. I examined the hypothesis that most birds breed at a time when reproductive potential is most fully realised. By using the numbers of Jackass Penguins returning to the island per 24 hour period as an index of the number of birds breeding, I found that most penguins on the island bred when chick growth was maximal and chick mortality was minimal. The diet of Jackass Penguins was determined by stomach pumping 556 birds. More than 95% of their diet, by weight, consisted of pelagic schooling fish. The local abundance of these fish seemed to determine the breeding success of the Jackass Penguin.
Jahreszeitliche Unterschiede in Nahrung und Bruterfolg des BrillenpinguinsSpheniscus demersus
Zusammenfassung Brillenpinguine brüten zwar das ganze Jahr hindurch, zeigen aber jahreszeitliche Präferenzen. Ich prüfte die Hypothese, daß die meisten Vögel zu der Zeit nisten, wenn der höchste Bruterfolg realisiert werden kann. Die Anzahl pro 24-h-Perioden auf die Insel rückkehrender Pinguine wurde als Index für den Brutbestand betrachtet. Tatsächlich brüteten am meisten Vögel dann, als Wachstum maximal und Kükensterblichkeit minimal waren. Die Nahrung wurde durch Magenspülungen bei 556 Individuen ermittelt. Pelagische Schwarmfische machten mehr als 95 Gewichtsprozente aus. Anscheinend bestimmte die lokale Häufigkeit dieser Fische den Bruterfolg.相似文献
86.
Platelet‐derived growth factor regulates YAP transcriptional activity via Src family kinase dependent tyrosine phosphorylation 下载免费PDF全文
87.
Glyoxal as an alternative fixative to formaldehyde in immunostaining and super‐resolution microscopy 下载免费PDF全文
Katharina J Seitz Martin S Helm Deblina Sarkar Rebecca S Saleeb Elisa D'Este Jessica Eberle Eva Wagner Christian Vogl Diana F Lazaro Frank Richter Javier Coy‐Vergara Giovanna Coceano Edward S Boyden Rory R Duncan Stefan W Hell Marcel A Lauterbach Stephan E Lehnart Tobias Moser Tiago F Outeiro Peter Rehling Blanche Schwappach Ilaria Testa Bolek Zapiec Silvio O Rizzoli 《The EMBO journal》2018,37(1):139-159
Paraformaldehyde (PFA) is the most commonly used fixative for immunostaining of cells, but has been associated with various problems, ranging from loss of antigenicity to changes in morphology during fixation. We show here that the small dialdehyde glyoxal can successfully replace PFA. Despite being less toxic than PFA, and, as most aldehydes, likely usable as a fixative, glyoxal has not yet been systematically tried in modern fluorescence microscopy. Here, we tested and optimized glyoxal fixation and surprisingly found it to be more efficient than PFA‐based protocols. Glyoxal acted faster than PFA, cross‐linked proteins more effectively, and improved the preservation of cellular morphology. We validated glyoxal fixation in multiple laboratories against different PFA‐based protocols and confirmed that it enabled better immunostainings for a majority of the targets. Our data therefore support that glyoxal can be a valuable alternative to PFA for immunostaining. 相似文献
88.
Melanie S. Johnson James Simpson David J. MacEwan Angela Ison Roger A. Clegg Kevin Connor Rory Mitchell 《Molecular and cellular biochemistry》1995,146(2):127-137
The characteristics of PKC activation induced by a number of compounds were investigated using PKCs, partially-purified from sources with a naturally high abundance of certain Ca2+ dependent PKC isoforms. Native isoforms were used rather than PKC isoforms expressed from a baculovirus system to assess the effect of tissue specific factors on activity. However, some data using recombinant PKC were included for comparison.The presence of specific PKC isoforms in different tissues was determined using Western blot analysis. Protein kinase C , 1, , , and / were all present in rat midbrain cytosolic extract, PKC , 1, , and / were present in spleen cytosol, and PKC and / were present in COS 7 cell cytosol. The predominance of and activities in COS 7 and spleen extracts respectively was confirmed by enzymic assay.The PKC activity assay was configured such that the Ca2+ dependence of the PKC activity induced by different PKC activators could be determined. Phorbol 12,13-dibutyrate (PDBu) was virtually equipotent on the Ca2+-dependent PKC activity from midbrain and spleen and slightly less potent on that from COS 7 cells. In the absence of Ca2+, PDBu was considerably less potent overall (as, indeed, were the other PKC activators) and was less potent on COS 7 cell PKC than on those from midbrain or spleen. Mezerein was more potent than PDBu at inducing PKC activity in COS 7 cell extracts in either the absence or presence of Ca2+ whereas in the presence of Ca2+, mezerein was slightly less potent on midbrain and spleen than PDBu and equipotent in the absence of Ca2+. Maximum values for Ca2+-independent activation by mezerein indicated that this activator was particularly effective in recruiting Ca2+-dependent PKC isoform activity in a Ca2+ free environment. The greater potency of mezerein on PKC was confirmed using PKC and further purified from rat spleen by hydroxylapatite (HAP) chromatography. The effects of both PDBu and mezerein were investigated using anterior pituitary tissue where a particularly high potency of mezerein in the absence of Ca2+ was noted. The diacylglycerol, 1,2-dioctanoyl-sn-glycerol (DOG), appeared to cause little or no activation of native Ca2+-dependent isoforms in Ca2+ free conditions unlike another longer chain diacylglycerol, 1,2-dioleoyl-sn-glycerol. Also DOG activated midbrain PKCs more potently than PKCs from spleen or COS 7 cells (or lung and pituitary tissue) in the presence of Ca2+. The concentration-dependence of DOG was examined on PKC and PKC further purified from brain by HAP chromatography, revealing that DOG was equally potent on both of these isoforms derived from brain and on recombinant PKC . However, [3H]PDBu binding data using PKC purified from several sources gave very different IC50 values when DOG was used as a displacer, and in general these values correlated with the EC50 values recorded from the activity assay.The data presented here indicate that there are distinct differences in the activator pharmacology of different native PKC isoforms and between the same isoform expressed in different tissues, either because of post-translational modifications or some other tissue specific factor. 相似文献
89.
Turning the tables of sex distinction in craniofacial identification: Why females possess thicker facial soft tissues than males,not vice versa 下载免费PDF全文
Carl N. Stephan Rory Preisler Ozgur Bulut Mike Bennett 《American journal of physical anthropology》2016,161(2):283-295
Males are universally reported to possess larger facial soft‐tissue thickness (FSTT) than females, however, this observation oversimplifies the raw data yielding an underpowered assessment of FSTT sex‐patterning where: differences are small (η2 < 5%) and inconsistent (females are routinely larger than males at the cheeks). Here we investigate body‐size normalized data to assess whether more general and improved understanding of FSTT sex‐variation in humans is possible. FSTTs were measured in 52 healthy living Australians aged 18 to 30 years using B‐mode ultrasound. Participants' stature and body mass were also measured. Sex differences were calculated before and after normalization by the aforementioned body‐composition variables. Methods were repeated in three other independent samples to evaluate reproducibility: 100 American Whites and 60 American Blacks measured by B‐mode ultrasound; and 50 Turkish residents measured by regular supine CT. Compared to raw mean differences (F < M, by ?6%), females displayed much thicker FSTTs than males when normalized for body mass (F > M, by +16%). Consequently, while the sexes share similar raw values, females possess much larger FSTTs for their relatively lighter bodies. The relative FSTT difference was 2.7× larger than the raw mean difference. Sex differences in FSTT are of larger magnitude and reversed direction in mass normalized data. Contrary to popular thought, females possess much larger FSTTs than males owing to their generically lighter bodies (?18 kg). These data patterns help explain why the pooling of sex‐categorized FSTT does not jeopardize the sex‐difference—it is encoded more strongly in terms relative to body mass. 相似文献
90.
Fiona Bragg Liming Li Ling Yang Yu Guo Yiping Chen Zheng Bian Junshi Chen Rory Collins Richard Peto Chunmei Wang Caixia Dong Rong Pan Jinyi Zhou Xin Xu Zhengming Chen China Kadoorie Biobank collaborative group 《PLoS medicine》2016,13(7)
BackgroundIn China, diabetes prevalence is rising rapidly, but little is known about the associated risks and population burden of cardiovascular diseases. We assess associations of diabetes with major cardiovascular diseases and the relevance of diabetes duration and other modifiable risk factors to these associations.ConclusionsAmong Chinese adults, diabetes is associated with significantly increased risks of major cardiovascular diseases. The increasing prevalence and younger age of onset of diabetes foreshadow greater diabetes-attributable disease burden in China. 相似文献