Human monocytes/macrophages (M psi) were infected with Histoplasma capsulatum yeast cells, and intracellular growth was quantified after 24 h of incubation in medium alone or in medium containing cytokines. Yeast cells multiplied within freshly isolated monocytes, cultured M psi, and alveolar M psi with intracellular generation times of 14.2 +/- 1.4, 18.5 +/- 2.1, and 19.9 +/- 1.9 h (mean +/- s...

A native PSI complex and a PSI core complex have been isolated from the halophilic green alga, Dunaliella salina. The composition and properties of these complexes are similar to previously described PSI complexes from spinach membranes. By growth on (14)C-NaHCO(3), it has been possible to isolate uniformly labeled (14)C-PSI complexes in order to determine PSI subunit stoichiometry. This analys...

The Agency for Healthcare Research and Quality Patient Safety Indicators (PSIs) do not capture complications arising after discharge. This study sought to quantify the bias related to omission of readmissions for PSI-qualifying conditions. Using 2000-2009 California Office of Statewide Health Planning and Development Patient Discharge Data, the study team examined the change in PSI rates when i...

Oxygenic photosynthesis is driven by photosystems I and II (PSI and PSII, respectively). Both have specific antenna complexes and the phycobilisome (PBS) is the major antenna protein complex in cyanobacteria, typically consisting of a core from which several rod-like subcomplexes protrude. PBS preferentially transfers light energy to PSII, whereas a PSI-specific antenna has not been identified....

Profiles of water potential (Psi w) were measured from the soil to the tips of growing leaves of maize (Zea mays L.) when pressure (P) was applied to the soil/root system. At moderately low soil Psi w, leaf elongation was somewhat inhibited, large tensions existed in the xylem, and Psi w were slightly lower in the elongating leaf tissues than in the xylem, i.e. a growth-induced Psi w was presen...

The ndhB(-) and psaE(-) mutants of the cyanobacterium Synechocystis sp. PCC 6803 are partly deficient in PSI-driven cyclic electron transport. We compared photoinhibition in these mutants to the wild type to test the hypothesis that PSI cyclic electron transport protects against photoinhibition. Photoinhibitory treatment greatly accelerated PSI cyclic electron transport in the wild type and als...

The data of 10 series of forced-choice experiments involving a variety of psi tasks and six high-scoring subjects were examined for nonrandomness in the within-run grouping of their hits. For two subjects, grouping analyses were also made of parallel visual series in which they tried to identify briefly-displayed slides of the same targets used in the psi tasks. Five of the six subjects showed ...

Prions are "infectious" proteins. When Sup35, a yeast translation termination factor, is aggregated in its [PSI(+)] prion form its function is compromised. When Rnq1 is aggregated in its [PIN(+)] prion form, it promotes the de novo appearance of [PSI(+)]. Heritable variants (strains) of [PSI(+)] with distinct phenotypes have been isolated and are analogous to mammalian prion strains with differ...

Yeast strains can reversibly interconvert between [PSI+] and [psi-] states. The [PSI+] state is caused by a prion form of the translation termination factor eRF3. The [PSI+] state causes read-through at stop codons and can lead to phenotypic variation, although the molecular mechanisms causing those phenotypic changes remain unknown. We identify an interaction between [PSI+]-induced phenotypic ...

Photosystem I (PSI) is a reaction center associated with oxygenic photosynthesis. Unlike the monomeric reaction centers in green and purple bacteria, PSI forms trimeric complexes in most cyanobacteria with a 3-fold rotational symmetry that is primarily stabilized via adjacent PsaL subunits; however, in plants/algae, PSI is monomeric. In this study, we discovered a tetrameric form of PSI in the ...