SERUM SOLUBLE ENDOGLIN IN PEDIATRIC SEPTIC SHOCK-ASSOCIATED MULTIPLE ORGAN DYSFUNCTION SYNDROME.

ABSTRACT: Background: Endothelial activation is a key driver of multiple organ dysfunction syndrome (MODS). Soluble endoglin (sENG) is expressed by mature and progenitor endothelial cells and thought to have angiogenic properties. We sought to determine the association between sENG and pediatric sepsis-associated MODS. Methods: Prospective observational study of pediatric septic shock. Primary outcome of interest was complicated course-a composite of death by (or) MODS on day 7 of illness. Secondary outcomes included individual organ dysfunctions. Endothelial biomarkers including sENG were measured using multiplex Luminex assays among patients with existing data on the Pediatric Sepsis Biomarker Risk Model (PERSEVERE-II) data. Multivariable regression was used to test the independent association between sENG and clinical outcomes. Serum sENG concentrations across PERSEVERE-II mortality risk strata and correlations with established markers of endothelial dysfunction were determined. Results: Three hundred six critically ill children with septic shock were included. Serum sENG concentrations were higher among those with primary and secondary outcomes of interest, with the exception of acute neurological dysfunction. Soluble endoglin was independently associated with increased odds of complicated course (adjusted odds ratio, 1.53; 95% confidence interval, 1.02-2.27; P = 0.038) and acute renal dysfunction (adjusted odds ratio, 1.84; 95% confidence interval, 1.18-2.876; P = 0.006). Soluble endoglin demonstrated graded responses across PERSEVERE-II risk strata and was positively correlated with endothelial biomarkers, except angiopoietin-1. Conclusions: Serum sENG is independently associated with complicated course and acute renal dysfunction in pediatric septic shock. Future studies are required to validate our observational data, and mechanistic studies are necessary to elucidate whether endoglin plays an organ-specific role in the development or resolution of acute renal dysfunction in sepsis.

Implementation of a food scholarship program improves nutrient intake and dietary quality of college students.

Objective: To determine the impact of a new food scholarship program on nutrient intake and dietary quality. Participants: College students (n = 49), female (78%), single (76%), average age 28 years, and white (49%). Methods: Fruits, vegetables, dairy, meat products and nonperishable foods were distributed twice a month. A one-group pretest post-test intervention compared baseline and 10 weeks data. Food security was measured and three-day food records assessed nutrient intake, Health Eating Index (HEI)-2015 (total and component) scores, and food group servings. Paired t-test at baseline and 10 weeks were performed (SPSS v25) (p < 0.05). Results: Prevalence of food insecurity did not change (baseline 53%, 10 weeks 47%). Protein, (p = 0.001), niacin (p = 0.002), magnesium (p = 0.034), phosphorous (p = 0.039), potassium (p = 0.019), and vegetable servings (p = 0.034) intake increased. Total HEI-2015 scores remained unchanged but HEI-2015 vegetable scores increased (p = 0.023). Conclusion: Increased intake of some nutrients and vegetable servings were achieved with the food scholarship program.

Gads-deficient thymocytes are blocked at the transitional single positive CD4+ stage.

Positive selection of T-cell precursors is the process by which a diverse T-cell repertoire is established. Positive selection begins at the CD4(+)CD8(+) double positive (DP) stage of development and involves at least two steps. First, DP thymocytes down-regulate CD8 to become transitional single positive (TSP) CD4(+) thymocytes. Then, cells are selected to become either mature single positive CD4(+) or mature single positive CD8(+) thymocytes. We sought to define the function of Gads during the two steps of positive selection by analyzing a Gads-deficient mouse line. In Gads(+/+) mice, most TSP CD4(+) thymocytes are TCR(hi)Bcl-2(hi)CD69(+), suggesting that essential steps in positive selection occurred in the DP stage. Despite that Gads(-/-) mice could readily generate TSP CD4(+) thymocytes, many Gads(-/-) TSP CD4(+) cells were TCR(lo)Bcl-2(lo)CD69(-), suggesting that Gads(-/-) cells proceeded to the TSP CD4(+) stage prior to being positively selected. These data suggest that positive selection is not a prerequisite for the differentiation of DP thymocytes into TSP CD4(+) thymocytes. We propose a model in which positive selection and differentiation into the TSP CD4(+) stage are separable events and Gads is only required for positive selection.

Antibiotic resistance of enterococci in American bison (Bison bison) from a nature preserve compared to that of Enterococci in pastured cattle.

Enterococci isolated from a bison population on a native tall-grass prairie preserve in Kansas were characterized and compared to enterococci isolated from pastured cattle. The species diversity was dominated by Enterococcus casseliflavus in bison (62.4%), while Enterococcus hirae was the most common isolate from cattle (39.7%). Enterococcus faecalis was the second most common species isolated from bison (16%). In cattle, E. faecalis and Enterococcus faecium were isolated at lower percentages (3.2% and 1.6%, respectively). No resistance to ampicillin, chloramphenicol, gentamicin, or high levels of vancomycin was detected from either source. Tetracycline and erythromycin resistance phenotypes, encoded by tetO and ermB, respectively, were common in cattle isolates (42.9% and 12.7%, respectively). A significant percentage of bison isolates (8% and 4%, respectively) were also resistant to these two antibiotics. The tetracycline resistance genes from both bison and cattle isolates resided on mobile genetic elements and showed a transfer frequency of 10(-6) per donor, whereas erythromycin resistance was not transferable. Resistance to ciprofloxacin was found to be higher in enterococci from bison (14.4%) than in enterococci isolated from cattle (9.5%). The bison population can serve as a sentinel population for studying the spread and origin of antibiotic resistance.

Activation of the caspase 8 pathway mediates seizure-induced cell death in cultured hippocampal neurons.

In response to harmful stresses, cells induce programmed cell death (PCD) or apoptosis. Seizures can induce neural damage and activate biochemical pathways associated with PCD. Since seizures trigger intracellular calcium overload, it has been presumed that the intrinsic cell death pathway mediated by mitochondrial dysfunction would modulate cell death following seizures. However, previous work suggests that the extrinsic cell death pathway may initiate the damage program. Here we investigate intrinsic versus extrinsic cell death pathway activation using caspase cleavage as a marker for activation of these pathways in a rat in vitro model of seizures. Hippocampal cells, chronically treated with kynurenic acid, had kynurenic acid withdrawn to induce seizure-like activity for 40 min. Subjecting rat hippocampal cultures to seizures increased cell death and apoptosis-like DNA fragmentation using TUNEL staining. Seizure-induced cell death was blocked by both MK801 (10 microM) and CNQX (40 microM), which suggests multiple glutamate receptors regulate seizure-induced cell death. Cleavage of the initiator caspases, caspase 8 and 12 were increased 4h following seizure, and cleavage of the quintessential executioner caspase, caspase 3 was increased 4h following seizure. In contrast, caspase 9 cleavage only increased 24h following seizure. Using an affinity labeling approach to trap activated caspases in situ, we show that caspase 8 is the apical caspase activated following seizures. Finally, we show that the caspase 8 inhibitor Ac-IETD-CHO was more effective at blocking seizure-induced cell death than the caspase 9 inhibitor Ac-LEHD-CHO. Taken together, our data suggests the extrinsic cell death pathway-associated caspase 8 is activated following seizures in vitro.

A genetic basis for atrophy: dominant non-responsiveness and helicobacter induced gastritis in F(1) hybrid mice.

BACKGROUND: The importance of host factors in helicobacter induced gastritis has been shown in animal models. Infection of most mouse strains with Helicobacter felis results in a functional atrophic gastritis, while other strains remain gastritis free. AIMS: To investigate these host factors further by using genetic crosses of responder and non-responder mice. METHODS: F(1) hybrids of the non-responder CBA/Ca strain and three strains of mice known to develop H felis induced gastritis were infected for three months with H felis. Gastritis was assessed by histopathology and serum antibody responses by ELISA. RESULTS: Infection of CBA/Ca mice and F(1) hybrids induced little or no gastritis. Analyses of the antibody responses in these mice revealed virtually undetectable anti-helicobacter antibody levels despite colonisation with high numbers of H felis. In contrast, infection of H felis responsive strains induced gastritis and a significant humoral immune response. CONCLUSIONS: The non-responsiveness of CBA/Ca mice to H felis infection is dominantly inherited. The lack of gastritis in CBA mice and their offspring is probably due to active suppression of the immune response normally mounted against H felis. Investigation of these mechanisms will provide important insights relevant to induction of gastric atrophy and cancer in humans.

Helicobacter pylori infection in immunized mice lacking major histocompatibility complex class I and class II functions.

The role of major histocompatibility complex (MHC) class I- and class II-restricted functions in Helicobacter pylori infection and immunity upon oral immunization was examined in vivo. Experimental challenge with H. pylori SS1 resulted in significantly greater (P

Multiplex sequencing of 1.5 Mb of the Mycobacterium leprae genome.

The nucleotide sequence of 1.5 Mb of genomic DNA from Mycobacterium leprae was determined using computer-assisted multiplex sequencing technology. This brings the 2.8-Mb M. leprae genome sequence to approximately 66% completion. The sequences, derived from 43 recombinant cosmids, contain 1046 putative protein-coding genes, 44 repetitive regions, 3 tRNAs, and 15 tRNAs. The gene density of one per 1.4 kb is slightly lower than that of Mycoplasma (1.2 kb). Of the protein coding genes, 44% have significant matches to genes with well-defined functions. Comparison of 1157 M. leprae and 1564 Mycobacterium tuberculosis proteins shows a complex mosaic of homologous genomic blocks with up to 22 adjacent proteins in conserved map order. Matches to known enzymatic, antigenic, membrane, cell wall, cell division, multidrug resistance, and virulence proteins suggest therapeutic and vaccine targets. Unusual features of the M. leprae genome include large polyketide synthase (pks) operons, inteins, and highly fragmented pseudogenes.

Development of 124 sequence-tagged sites and cytogenetic localization of 217 cosmids for human chromosome 10.

A total of 124 new chromosome 10-specific sequence-tagged sites (STSs) were derived from two sources: (1) DNA sequences obtained from anonymous clones in new libraries enriched for human chromosome 10 inserts, and (2) published sequences of genes and other loci already known to map to chromosome 10. Libraries were constructed from a somatic cell hybrid carrying human chromosomes 10 and Y. A cosmid library was made from total DNA of the hybrid and probed with labeled total human DNA to identify clones with human DNA inserts. Two hundred seventeen cosmids were mapped to regions of human chromosome 10 by fluorescence in situ hybridization. Twenty-five cosmids represent probes that have been placed on the genetic map previously. One hundred ninety-two cosmids represent new probes that have not been mapped previously. Cosmids carrying inserts with CA repeats were identified by hybridization with a labeled poly(dC-dA)-poly(dG-dT) probe and subcloned to yield microsatellite STS markers. Two small insert plasmid libraries were made, the first by subcloning inserts from a chromosome 10-enriched lambda phage library (LL10NS01) and the second by cloning Alu element-mediated PCR products amplified from hybrid DNA. STSs were generated from the DNA sequences of clone inserts. Chromosome 10-specific STSs were distinguished from Y chromosome STSs by one or both of the following criteria: (1) successful PCR amplification from a template consisting of DNA from another chromosome 10-containing cell line, NA10926B, or (2) FISH localization to chromosome 10 of the source cosmid or of YACs isolated by PCR screening with the STS. These libraries were the source of 90 new chromosome 10-specific STSs, 42 of which contain CA repeats.

A novel role for the 3' region of introns in pre-mRNA splicing of Saccharomyces cerevisiae.

To investigate the importance of sequences between the yeast (Saccharomyces cerevisiae) branch point (TACTAAC box) and 3' splice site (AG), we generated a series of pre-mRNA substrates that differed in the length of RNA retained on the 3' side of the TACTAAC box. These pre-mRNAs were compared as substrates for the first step of in vitro splicing (5' cleavage and lariat formation) and in vitro spliceosome assembly (complex formation) in a whole-cell yeast extract. The results indicate that for rp51A pre-mRNA at least 29 nucleotides of RNA on the 3' side of the TACTAAC box are required for 5' cleavage and lariat formation, as smaller substrates fail to manifest any detectable cleavage or ligation events. Analysis of splicing complex assembly indicates that these smaller substrates undergo efficient yet incomplete complex formation; they are blocked at a late stage of spliceosome assembly, the complex I to complex II transition (Pikielny et al. 1986), a result which suggests that the failure to form lariats is due to a specific assembly defect. The lariat formation block (and assembly defect) can be relieved by the addition of ribohomopolymer "tails" to the 3' end of the shortened rp51A pre-mRNAs, and similar results were obtained with shortened actin pre-mRNAs. The results of this study indicate that this region of the pre-mRNA serves a specific function late in in vitro spliceosome assembly.

Natural and synthetic heat shock protein gene promoters assayed in Drosophila cells.

Hybrid genes containing mRNA encoding sequences for herpes virus thymidine kinase (tk), chloramphenicol acetyltransferase (CAT), or Drosophila alcohol dehydrogenase (Adh), ligated to truncated Drosophila melanogaster heat-shock protein 70 (hsp 70) gene promoters or to synthetic sequences containing one or several copies of a previously defined heat-shock consensus sequence, were transfected into cultured Drosophila line S3 cells. Each construction was then assayed for gene expression at 25 degrees C and 37 degrees C, using a CAT enzyme assay, slot blot hybridization, or S1 nuclease protection analysis. In the Drosophila cell transient expression assay system, we found that deletions extending beyond position -97, or synthetic constructions containing a single heat shock consensus sequence, were not induced by high-temperature shock. In constructions containing deletions extending to position -186, -130, or -97, in the hsp 70 promoter, and in synthetic constructions containing tandemly spaced heat-shock consensus sequences mRNA transcription was greatly induced by high temperature.

Expression of Drosophila hsp 70-CAT hybrid gene in Aedes cells induced by heat shock.

DNA-mediated transfer of a Drosophila hsp 70-CAT hybrid gene into Drosophila S3 cells leads to the appearance of heat shock (37 degrees C)-inducible chloramphenicol acetyltransferase (CAT) activity. When this hybrid gene construction was transfected into cultured Aedes, Plodia, or Manduca cells, only trace levels of heat-inducible CAT activity were observed. Induction could be somewhat improved by using Schneider's Drosophila medium for transfection. In the case of Aedes cells, levels of CAT induction comparable to that seen using Drosophila cells could be achieved by raising the heat-shock temperature to 41 degrees C, a treatment which is lethal to Drosophila.