Myocardial improvement with human embryonic stem cell-derived cardiomyocytes enriched by p38MAPK inhibition

Background aimsWe have shown previously that inhibition of the p38 mitogen-activated protein kinase (p38MAPK) directs the differentiation of human embryonic stem cell (hESC)-derived cardiomyocytes (hCM). We investigated the therapeutic benefits of intramyocardial injection of hCM differentiated from hESC by p38MAPK inhibition using closed-chest ultrasound-guided injection at a clinically relevant time post-myocardial infarction (MI) in a mouse model.MethodsMI was induced in mice and the animals treated at day 3 with: (a) hCM, (b) human fetal fibroblasts (hFF) as cell control, or (c) medium control (n = 10 animals/group). Left ventricular ejection fraction (LVEF) was evaluated post-MI prior to therapy, and at days 28 and 60 post-cell therapy. Hearts were analyzed at day 60 for infarct size, angiogenesis, cell fate and teratoma formation.ResultsLVEF was improved in the hCM-treated animals compared with both hFF and medium control-treated animals at day 28 (39.03 ± 1.79% versus 27.89 ± 1.27%, P < 0.05, versus 32.90 ± 1.46%, P < 0.05, respectively), with sustained benefit until day 60. hCM therapy resulted in significantly smaller scar size, increased capillary bed area, increased number of arterioles, less native cardiomyocyte (CM) apoptosis, and increased CM proliferation compared with the other two groups. These benefits were achieved despite a very low retention rate of the injected cells at day 60, as assessed by immunohistochemistry and quantitative real-time polymerase chain reaction (qPCR). Therapy with hCM did not result in intramyocardial teratoma formation at day 60.ConclusionsThis study demonstrates that hCM derived from p38MAPK-treated hESC have encouraging therapeutic potential.     

Identification and characterization of plasmids in hydrogen uptake positive and hydrogen uptake negative strains ofRhizobium japonicum

Modifications were made of published procedures to allow routine isolation of plasmids fromRhizobium japonicum. The plasmid profiles of a series of H₂ uptake positive and H₂ uptake negative strains were compared. None of the strains ofR. japonicum with high H₂ uptake activities exhibited discernible plasmids, while most of the strains, with little or no H₂ uptake activity, showed plasmids with molecular weights ranging from approximately 49–290 x10⁶. An examination of H₂ uptake negative mutants derived from an H₂ uptake positive parent revealed two discernible plasmid bands in nonrevertible mutants but no detectable plasmids in revertible mutants or in the parent strain from which mutants were derived.     

Susceptibility of the Colorado Potato Beetle and the Sugarbeet Wireworm to Steinernema feltiae and S. glaseri

In laboratory tests, larvae of the Colorado potato beetle (CPB), Leptinotarsa decemlineata (Say), and the sugarbeet wireworm (SBW), Limonius californicus (Mannerheim), were exposed to the nematodes Steinernema feltiae Filipjev (Mexican strain) (= Neoaplectana carpocapsae) and S. glaseri Steiner in soil. S. feltiae caused significantly higher mortality in SBW larvae than did S. glaseri, but both nematode species were equally effective against CPB larvae. The minimum concentration of S. feltiae for 100% mortality of CPB larvae after 13 days was 157 nematodes/cm² of soil, and the LC₅₀ based on 6-day mortality was 47.5 nematodes/cm²; in contrast, 100% mortality of SBW larvae was not achieved with even the highest concentration tested, 393 nematodes/cm². CPB adults emerging from nematode-contaminated soil were not infected. In field cage tests, S. feltiae applied to the soil surface at the rates of 155 and 310 nematodes/cm² soil caused 59% and 71% mortality, respectively, of late-fourth-instar spring-generation CPB, and 28% and 29% mortality, respectively, of SBW. No infection was obtained when larvae of summer generation CPB and SBW were placed in the same cages approximately 6 weeks after nematodes were applied to the soil. Inundative soil applications of S. feltiae, though cost prohibitive at present, were effective in reducing caged CPB and SBW field populations.     

Calcified gallstone in a 3 year-old boy: a case report

ABSTRACT: BACKGROUND: Gallstones are relatively rare in children. At-risk populations include patients suffering from hemolysis syndromes. Regardless of etiology, these patients usually will present with postprandial abdominal pain, and ultrasonography is the mainstay of diagnosis. However, some gallstones are radiopaque and can be visualized on plain abdominal radiography. CASE PRESENTATION: We present the uncommon but classic plain x-ray finding of a calcified gallstone in a 3 year-old Hispanic boy. He was treated with elective laparoscopic cholecystectomy. CONCLUSIONS: Cholelithiasis is rare in children, and calcified stones that will appear on plain abdominal x-rays are even rarer. If symptomatic, cholecystectomy by a pediatric surgeon is the treatment of choice. We discuss some of the recent developments in treatment of this condition in this patient population.     

Induction of Specific MicroRNAs Inhibits Cutaneous Wound Healing

Chronic nonhealing wounds, such as venous ulcers (VUs), are a widespread and serious medical problem with high morbidity and mortality. The molecular pathology of VUs remains poorly understood, impeding the development of effective treatment strategies. Using mRNA expression profiling of VUs biopsies and computational analysis, we identified a candidate set of microRNAs with lowered target gene expression. Among these candidates, miR-16, -20a, -21, -106a -130a, and -203 were confirmed to be aberrantly overexpressed in a cohort study of 10 VU patients by quantitative PCR and in situ hybridizations. These microRNAs were predicted to target multiple genes important for wound healing, including early growth response factor 3, vinculin, and leptin receptor (LepR). Overexpression of the top up-regulated miRNAs, miR-21 and miR-130a, in primary human keratinocytes down-regulated expression of the endogenous LepR and early growth response factor 3. The luciferase reporter assay verified LepR as a direct target for miR-21 and miR-130a. Both miR-21 and miR-130a delayed epithelialization in an acute human skin wound model. Furthermore, in vivo overexpression of miR-21 inhibited epithelialization and granulation tissue formation in a rat wound model. Our results identify a novel mechanism in which overexpression of specific set of microRNAs inhibits wound healing, resulting in new potential molecular markers and targets for therapeutic intervention.     

Predicting therapy response in live tumor cells isolated with the flexible micro spring array device

Cells disseminated from primary epithelial tumors into peripheral blood, called circulating tumor cells (CTCs), can be monitored to assess metastases and to provide a surrogate marker of treatment response. Here, we demonstrate how the flexible micro spring array (FMSA) device—a novel microfluidic device that enriches CTCs by two physical parameters: size and deformability—could be used in the rational development of treatment intervention and as a method to study the fundamental biology of CTCs. Cancer cells of different origins were spiked into healthy samples of donor blood to mimic blood samples of metastatic cancer patients. This spiked human blood was filtered using the FMSA device, and the recovered cells were successfully expanded in vitro and in a novel in vivo system. A series of experiments were performed to characterize these cells and to investigate the effect of chemotherapy on the resulting cultures. As few as 20 colon cancer cells in 7.5 mL blood could be isolated with the FMSA device, expanded both in vitro and in vivo and used at 25 cells per well to obtain significant and reliable chemosensitivity data. We also show that isolating a low number of viable patient CTCs and maintaining them in culture for a few weeks is possible. The isolation of viable cancer cells from human blood using the FMSA device provides a novel and realistic means for studying the biology of viable CTCs and for testing drug efficacy on these rare cells—a hypothesis that can be tested in future clinical trials.     

Trends in Cardiac Biomarker Testing in China for Patients with Acute Myocardial Infarction, 2001 to 2011: China PEACE-Retrospective AMI Study

Objectives

To describe trends in the availability of biomarker testing in Chinese hospitals and how practice complies with established standards for the diagnosis of acute myocardial infarction (AMI).

Background

Cardiac biomarker testing is standard in high-income countries, but little is known about the availability and use of cardiac biomarker testing in low- and middle-income countries (LMICs) such as China.

Methods

Based on a nationally representative sample of Chinese hospitals in 2001, 2006 and 2011, we describe the temporal trends and regional differences in the hospital capability and rates of use of cardiac biomarker testing, as well as the variation in use across hospitals with testing capability, for patients labeled with the diagnosis of AMI.

Results

We sampled 175 hospitals (162 participated in the study) and 18,631 AMI admissions. 14,370 patients were included in analysis of biomarker use. The proportion of hospitals with biomarker testing capability was 57.4% in 2001 (25.0% troponin and 32.4% creatine kinase MB fraction (CK-MB) only) and 96.3% (81.4% troponin and 14.9% CK-MB only) in 2011. The proportion of hospitals with troponin testing capability in 2011 was significantly higher in urban compared with rural hospitals (96.8% vs. 71.4%, p< 0.001). In 2011, only 55.9% of hospitals with troponin testing capability (71 out of 127 hospitals) used the assay for more than 80% of their patients with AMI. Among hospitals with either biomarker testing capability, there was marked variation in use in both rural (from 7.1% to 100.0% of patients) and urban hospitals (from 57.9% to 100.0% of patients). In 2011, 36.1% of the patients with AMI did not have troponin tested and 4.9% did not have either biomarker measured.

Conclusions

The recommended biomarker tests for AMI diagnosis are not universally available and the testing is not consistently applied when it is available in China.

Trial Registration

ClinicalTrials.gov NCT01624883     

BIOTIC RELATIONSHIPS BETWEEN SOIL ALGAE AND OTHER MICROORGANISMS

Parker , Bruce C., and Harold C. Bold . (U. Texas, Austin.) Biotic relationships between soil algae and other microorganisms. Amer. Jour. Bot. 48(2): 185–197. Illus. 1961.—A study was conducted of biotic relationships between various algae and other microorganisms isolated from a sample of Texas soil. From 143 two-membered combinations of organisms tested in soil-water cultures, 3 were selected for detailed studies of the nature of the causal mechanisms of the associative effects. These were: (1) an association between a species of Bracteacoccus (Br. A-20) and a heterotrophic bacterium (B-6); (2) an association between a species of Chlamydomonas (Ch. 10) and a species of Streptomyces (Act-1); and (3) an association between a blue-green alga, Phormidium sp. (Ph. 14), and an as-yet-unidentified fungus (F-2). In the first association, the heterotrophic bacterium increased growth of Bracteacoccus up to 20 times in soil-water culture; the chief cause of stimulation was shown by a series of experiments to be the decomposition by the bacterium of complex nitrogenous substrates in the soil resulting in the release of simplified products which were available to the alga as a nitrogen source. In soil-water culture, Streptomyces (Act-1) enhanced the growth and motility of Chlamydomonas (Ch. 10) and induced akinetogenesis in the alga, while the actinomycete itself was stimulated in growth and production of conidia. The mutual stimulation was shown to be caused, in part, by carbon dioxide-oxygen interchange between the organisms. Motility of Ch. 10 was enhanced by a decrease in nitrogen as a result of the growth of Act-1 and by the ability of Act-1 to decompose and assimilate the extracellular polysaccharide of the alga. The assimilation of the extracellular polysaccharide by the actinomycete promoted its growth and conidia production. Initiation of akinetogenesis in Chlamydomonas occurred exclusively in close association with the filaments of Streptomyces in soil-water cultures, and only when the concentration of available nitrogen dropped below a critical level. The akinetogenic factor has not yielded to isolation and identification, but there is some suggestion that it may be an antibiotic substance. Phormidium (Ph. 14) was frequently antagonized and annihilated by fungus 2 in the soil-water medium. Attempts to extract growth inhibitors from filtrates of the fungal medium were unsuccessful. Indirect evidence suggested that perhaps the consumption of extracellular polysaccharide with concomitant release of organic acid by the fungus might be the factor inhibiting growth of Phormidium. Attempts to confirm experimentally the ecological significance for these biotic relationships are reported.