Investigation and study of a multi-aperture antenna system final report, 1 jan. - 1 apr. 1964

Multiple aperture adaptive antenna system for telemetry reception from remote space vehicle

Bacteria Modulate the CD8+ T Cell Epitope Repertoire of Host Cytosol-Exposed Proteins to Manipulate the Host Immune Response

The main adaptive immune response to bacteria is mediated by B cells and CD4+ T-cells. However, some bacterial proteins reach the cytosol of host cells and are exposed to the host CD8+ T-cells response. Both gram-negative and gram-positive bacteria can translocate proteins to the cytosol through type III and IV secretion and ESX-1 systems, respectively. The translocated proteins are often essential for the bacterium survival. Once injected, these proteins can be degraded and presented on MHC-I molecules to CD8+ T-cells. The CD8+ T-cells, in turn, can induce cell death and destroy the bacteria's habitat. In viruses, escape mutations arise to avoid this detection. The accumulation of escape mutations in bacteria has never been systematically studied. We show for the first time that such mutations are systematically present in most bacteria tested. We combine multiple bioinformatic algorithms to compute CD8+ T-cell epitope libraries of bacteria with secretion systems that translocate proteins to the host cytosol. In all bacteria tested, proteins not translocated to the cytosol show no escape mutations in their CD8+ T-cell epitopes. However, proteins translocated to the cytosol show clear escape mutations and have low epitope densities for most tested HLA alleles. The low epitope densities suggest that bacteria, like viruses, are evolutionarily selected to ensure their survival in the presence of CD8+ T-cells. In contrast with most other translocated proteins examined, Pseudomonas aeruginosa's ExoU, which ultimately induces host cell death, was found to have high epitope density. This finding suggests a novel mechanism for the manipulation of CD8+ T-cells by pathogens. The ExoU effector may have evolved to maintain high epitope density enabling it to efficiently induce CD8+ T-cell mediated cell death. These results were tested using multiple epitope prediction algorithms, and were found to be consistent for most proteins tested

Pseudomonas aeruginosa Population Structure Revisited

At present there are strong indications that Pseudomonas aeruginosa exhibits an epidemic population structure; clinical isolates are indistinguishable from environmental isolates, and they do not exhibit a specific (disease) habitat selection. However, some important issues, such as the worldwide emergence of highly transmissible P. aeruginosa clones among cystic fibrosis (CF) patients and the spread and persistence of multidrug resistant (MDR) strains in hospital wards with high antibiotic pressure, remain contentious. To further investigate the population structure of P. aeruginosa, eight parameters were analyzed and combined for 328 unrelated isolates, collected over the last 125 years from 69 localities in 30 countries on five continents, from diverse clinical (human and animal) and environmental habitats. The analysed parameters were: i) O serotype, ii) Fluorescent Amplified-Fragment Length Polymorphism (FALFP) pattern, nucleotide sequences of outer membrane protein genes, iii) oprI, iv) oprL, v) oprD, vi) pyoverdine receptor gene profile (fpvA type and fpvB prevalence), and prevalence of vii) exoenzyme genes exoS and exoU and viii) group I pilin glycosyltransferase gene tfpO. These traits were combined and analysed using biological data analysis software and visualized in the form of a minimum spanning tree (MST). We revealed a network of relationships between all analyzed parameters and non-congruence between experiments. At the same time we observed several conserved clones, characterized by an almost identical data set. These observations confirm the nonclonal epidemic population structure of P. aeruginosa, a superficially clonal structure with frequent recombinations, in which occasionally highly successful epidemic clones arise. One of these clones is the renown and widespread MDR serotype O12 clone. On the other hand, we found no evidence for a widespread CF transmissible clone. All but one of the 43 analysed CF strains belonged to a ubiquitous P. aeruginosa “core lineage” and typically exhibited the exoS+/exoU− genotype and group B oprL and oprD alleles. This is to our knowledge the first report of an MST analysis conducted on a polyphasic data set

Population Structure of Pseudomonas aeruginosa from Five Mediterranean Countries: Evidence for Frequent Recombination and Epidemic Occurrence of CC235

Several studies in recent years have provided evidence that Pseudomonas aeruginosa has a non-clonal population structure punctuated by highly successful epidemic clones or clonal complexes. The role of recombination in the diversification of P. aeruginosa clones has been suggested, but not yet demonstrated using multi-locus sequence typing (MLST). Isolates of P. aeruginosa from five Mediterranean countries (n = 141) were subjected to pulsed-field gel electrophoresis (PFGE), serotyping and PCR targeting the virulence genes exoS and exoU. The occurrence of multi-resistance (≥3 antipseudomonal drugs) was analyzed with disk diffusion according to EUCAST. MLST was performed on a subset of strains (n = 110) most of them had a distinct PFGE variant. MLST data were analyzed with Bionumerics 6.0, using minimal spanning tree (MST) as well as eBURST. Measurement of clonality was assessed by the standardized index of association (IAS). Evidence of recombination was estimated by ClonalFrame as well as SplitsTree4.0. The MST analysis connected 70 sequence types, among which ST235 was by far the most common. ST235 was very frequently associated with the O11 serotype, and frequently displayed multi-resistance and the virulence genotype exoS−/exoU+. ClonalFrame linked several groups previously identified by eBURST and MST, and provided insight to the evolutionary events occurring in the population; the recombination/mutation ratio was found to be 8.4. A Neighbor-Net analysis based on the concatenated sequences revealed a complex network, providing evidence of frequent recombination. The index of association when all the strains were considered indicated a freely recombining population. P. aeruginosa isolates from the Mediterranean countries display an epidemic population structure, particularly dominated by ST235-O11, which has earlier also been coupled to the spread of ß-lactamases in many countries

Family planning competency following medical school Ob/Gyn clerkships at faith-based and secular sites

Abstract Contraception and abortion topics are variably, but often poorly, addressed in medical school curricula. Restrictions on contraceptive and abortion care at faith-based hospitals may hinder comprehensive family planning training for medical students during Ob/Gyn clerkships. Here we investigated whether medical students at faith-based and non-faith-based clerkships experienced different observations during their Ob/Gyn clerkship and/or differences in self-perceived competency in patient counseling, objective knowledge, and perceived adequacy of training in contraception and abortion topics post-clerkship. A survey was distributed to third- and fourth-year medical students at New York Institute of Technology, College of Osteopathic Medicine. Across all clerkship sites (n = 102 students), observations of, and competency in, contraceptive care was higher than in abortion care. Students at non-faith-based clerkship sites (n = 54) reported the highest levels of observation of contraceptive and abortion care (19.6–90.7%), while those at Catholic sites (n = 26) typically reported the lowest (7.7–34.6%). Students at non-faith-based sites reported significantly higher competency in contraceptive care and some aspects of abortion care, than those at Catholic, and some other faith-based sites (n = 48). Clerkship training at faith-based sites, specifically Catholic sites, resulted in poorer Ob/Gyn training, particularly in contraceptive care. Training outcomes in abortion care were poor at all Ob/Gyn clerkship sites

Possibility of acceleration of polarized protons in the Brookhaven AGS

The unexpected importance of high energy spin effects and the success of the 12 GeV Argonne ZGS in jumping many intrinsic and imperfection depolarizing resonances suggests that polarized proton acceleration should be tried at higher energy. The 1977 Ann Arbor Workshop concluded that it might be possible to jump depolarizing resonances in strong focusing synchrotrons. During the past year we have evaluated the possibility of accelerating polarized protons in the Brookhaven AGS. We found that for about $2 million one could obtain a polarized ion source, fast resonance jumping magnets, and 3 polarimeters which should allow acceleration of 10/sup 11/ to 10/sup 12/ polarized protons to 23 GeV/c with about 70= polarization or to 26 GeV/c with about 50% polarization

Variability of care practices for extremely early deliveries

Objectives: Assess temporal changes, intercenter variability, and birthing person (BP) factors relating to interventions for extremely early deliveries. Methods: Retrospective study of BPs and newborns delivered from 22-24 completed weeks at 13 US centers from 2011-2020. Rates of neonatology consultation, antenatal corticosteroids, cesarean delivery, live birth, attempted resuscitation (AR), and survival were assessed by epoch, center, and gestational age. Results: 2028 BPs delivering 2327 newborns were included. Rates increased in epoch 2-at 22 weeks: neonatology consultation (37.6 vs 64.3%, P \u3c .001), corticosteroids (11.4 vs 29.5%, P \u3c .001), live birth (66.2 vs 78.6%, P \u3c .001), AR (20.1 vs 36.9%, P \u3c .001), overall survival (3.0 vs 8.9%, P = .005); and at 23 weeks: neonatology consultation (73.0 vs 80.5%, P = .02), corticosteroids (63.7 vs 83.7%, P \u3c .001), cesarean delivery (28.0 vs 44.7%, P \u3c .001), live birth (88.1 vs 95.1%, P \u3c .001), AR (67.7 vs 85.2%, P \u3c .001), survival (28.8 vs 41.6%, P \u3c .001). Over time, intercenter variability increased at 22 weeks for corticosteroids (interquartile range 18.0 vs 42.0, P = .014) and decreased at 23 for neonatology consultation (interquartile range 23.0 vs 5.2, P = .045). In BP-level multivariate analysis, AR was associated with increasing gestational age and birth weight, Black BP race, previous premature delivery, and delivery center. Conclusions: Intervention rates for extremely early newborns increased and intercenter variability changed over time. In BP-level analysis, factors significantly associated with AR included Black BP race, previous premature delivery, and center