Large, long range tensile forces drive convergence during

Indirect evidence suggests that blastopore closure during gastrulation of anamniotes, including amphibians such as Xenopus laevis, depends on circumblastoporal convergence forces generated by the marginal zone (MZ), but direct evidence is lacking. We show that explanted MZs generate tensile convergence forces up to 1.5 mN during gastrulation and over 4 mN thereafter. These forces are generated by convergent thickening (CT) until the midgastrula and increasingly by convergent extension (CE) thereafter. Explants from ventralized embryos, which lack tissues expressing CE but close their blastopores, produce up to 2 mN of tensile force, showing that CT alone generates forces sufficient to close the blastopore. Uniaxial tensile stress relaxation assays show stiffening of mesodermal and ectodermal tissues around the onset of neurulation, potentially enhancing long-range transmission of convergence forces. These results illuminate the mechanobiology of early vertebrate morphogenic mechanisms, aid interpretation of phenotypes, and give insight into the evolution of blastopore closure mechanisms. © Shook et al

Determining the Annual Risk of TB Infection among Health Care Workers in a Public Hospital in South Africa Using the Interferon Gamma Release Assay

While TB disease rates are leveling off or declining in most of the world, with one third of humanity infected and 1.8 million deaths a year, it remains a major public health problem. The main threat to global public health from TB is the continually increasing number of infections and increasing resistance to treatment in sub-Saharan Africa. Health care workers are at high risk for TB and their loss to the infections of TB and HIV is adding further strain to an already fragile health system. Research done thus far on the rate HCWs become infected with TB is limited, and the difference in risk among various occupational groups is unclear. Methods of TB control and prevention have been effective in wealthy countries and in the few middle income countries that have implemented them in limited settings. It remains unclear, however, if these methods can protect health care workers in high risk areas. Also unclear is which infection control interventions, if any, carry practical benefits that outweigh their costs in high risk areas. It is too difficult to evaluate these questions with the common test for L TBI (TST) because the TST is a poorly effective test, both non-sensitive and non-specific in the high-risk TB settings of subSaharan Africa. A new test for L TBI is now available, the IGRA. The IGRA has some qualities that may make it a better test for evaluating TB exposure in HCWs. This pilot study proposes to use an IGRA to estimate the annual risk of newly established and transient MTB infections in health care workers employed in a setting with high rates of TB and HIV. We will focus on two different groups of HCWs. First we will follow the risks of conversion as well as reversion and variability of the IGRA as compared to TST in nurses and technicians working in TB clinics. This is an expansion of the study of 10 HCWs done by Joshi et al in India. We will use the data to gain a better understanding of the use of the IGRA in high risk settings. Second we will evaluate baseline risk of conversion in students whose risk profile should parallel the general population at baseline then increase to that of HCWs as they begin working in clinical medicine and have increased patient contact. We aim to use this methodology and baseline information to plan future studies to assess the effectiveness of TB infection control measures in prospective controlled trials within health care settings in subSaharan Africa.Master of Public Healt

Stump appendicitis.

Stump appendicitis is a rare and late complication following appendectomy and can often be overlooked. Our case details a 42-year-old male who presented to the Emergency Department with right-sided lower abdominal pain, nausea, and vomiting. A computed tomography scan of his abdomen and pelvis demonstrated a tubular, fluid-filled structure with surrounding inflammatory changes at the level of the patient\u27s appendectomy clips with a 2.3-cm calcified intraluminal stone. Findings were concerning for stump appendicitis with appendicolith. He was admitted and taken to the operating room for a laparoscopic stump appendectomy. Stump appendicitis should always be considered in the differential diagnosis to prevent potentially serious complications

The role of the corpus callosum in seizure spread: MRI lesion mapping in oligodendrogliomas

Our data suggest that the genu of the corpus callosum may be a major pathway for seizure generalization in patients with oligodendrogliomas

Detecting temporal and spatial effects of epithelial cancers with Raman spectroscopy.

PublishedJournal ArticleResearch Support, N.I.H., ExtramuralResearch Support, Non-U.S. Gov'tThis is the final version of the article. Available from Hindawi Publishing Corporation via the DOI in this record.Epithelial cancers, including those of the skin and cervix, are the most common type of cancers in humans. Many recent studies have attempted to use Raman spectroscopy to diagnose these cancers. In this paper, Raman spectral markers related to the temporal and spatial effects of cervical and skin cancers are examined through four separate but related studies. Results from a clinical cervix study show that previous disease has a significant effect on the Raman signatures of the cervix, which allow for near 100% classification for discriminating previous disease versus a true normal. A Raman microspectroscopy study showed that Raman can detect changes due to adjacent regions of dysplasia or HPV that cannot be detected histologically, while a clinical skin study showed that Raman spectra may be detecting malignancy associated changes in tissues surrounding nonmelanoma skin cancers. Finally, results of an organotypic raft culture study provided support for both the skin and the in vitro cervix results. These studies add to the growing body of evidence that optical spectroscopy, in this case Raman spectral markers, can be used to detect subtle temporal and spatial effects in tissue near cancerous sites that go otherwise undetected by conventional histology.The authors acknowledge the financial support of the NCI/NIH (R01-CA95405 and R21-CA95995), as well as the Howard Hughes Medical Institute (pre-doctoral fellowship for MK). We would also like to thank the doctors and staff at Vanderbilt University Medical Center and Tri-state Women’s Health for all their assistance

Differential Expressed Genes Identified Between African American and European American Keloid Fibroblasts

Keloids are benign fibroproliferative tumors due to dysregulation of collagen remodeling and abnormal wound healing. Although worldwide, there is a higher incidence of keloid disease (KD) in skin of color, little is known about this predisposition. In this study, we used one tissue micro array slide comprised of six AA and 6 EA punch biopsies of primary untreated keloid tissue from the head and neck area was created, following the NanoString® DSP Technology Access Program protocol. The GeoMx Human Whole Transcriptome Atlas Assay was performed, using morphology marker FAP. Polygonal region of interests selection strategy for Fibroblast Activation Protein (FAP) positive cells was conducted. Univariate analysis was performed, using linear regression models to identify differentially expressed genes (DEG) at a false discovery rate (FDR) of 0.05. Ingenuity pathway analysis (IPA) software was used to determine DEG pathway enrichment. 1,450 DEG were identified (p-va

Towards a quantum representation of the ampere using single electron pumps

Electron pumps generate a macroscopic electric current by controlled manipulation of single electrons. Despite intensive research towards a quantum current standard over the last 25 years, making a fast and accurate quantised electron pump has proved extremely difficult. Here we demonstrate that the accuracy of a semiconductor quantum dot pump can be dramatically improved by using specially designed gate drive waveforms. Our pump can generate a current of up to 150 pA, corresponding to almost a billion electrons per second, with an experimentally demonstrated current accuracy better than 1.2 parts per million (ppm) and strong evidence, based on fitting data to a model, that the true accuracy is approaching 0.01 ppm. This type of pump is a promising candidate for further development as a realisation of the SI base unit ampere, following a re-definition of the ampere in terms of a fixed value of the elementary charge.Comment: 8 pages, 7 figure

On the Complex Network Structure of Musical Pieces: Analysis of Some Use Cases from Different Music Genres

This paper focuses on the modeling of musical melodies as networks. Notes of a melody can be treated as nodes of a network. Connections are created whenever notes are played in sequence. We analyze some main tracks coming from different music genres, with melodies played using different musical instruments. We find out that the considered networks are, in general, scale free networks and exhibit the small world property. We measure the main metrics and assess whether these networks can be considered as formed by sub-communities. Outcomes confirm that peculiar features of the tracks can be extracted from this analysis methodology. This approach can have an impact in several multimedia applications such as music didactics, multimedia entertainment, and digital music generation.Comment: accepted to Multimedia Tools and Applications, Springe

Dietary elimination of children with food protein induced gastrointestinal allergy – micronutrient adequacy with and without a hypoallergenic formula?

Background: The cornerstone for management of Food protein-induced gastrointestinal allergy (FPGIA) is dietary exclusion; however the micronutrient intake of this population has been poorly studied. We set out to determine the dietary intake of children on an elimination diet for this food allergy and hypothesised that the type of elimination diet and the presence of a hypoallergenic formula (HF) significantly impacts on micronutrient intake. Method: A prospective observational study was conducted on children diagnosed with FPIGA on an exclusion diet who completed a 3 day semi-quantitative food diary 4 weeks after commencing the diet. Nutritional intake where HF was used was compared to those without HF, with or without a vitamin and mineral supplement (VMS). Results: One-hundred-and-five food diaries were included in the data analysis: 70 boys (66.7%) with median age of 21.8 months [IQR: 10 - 67.7]. Fifty-three children (50.5%) consumed a HF and the volume of consumption was correlated to micronutrient intake. Significantly (p <0.05) more children reached their micronutrient requirements if a HF was consumed. In those without a HF, some continued not to achieve requirements in particular for vitamin D and zinc, in spite of VMS. Conclusion: This study points towards the important micronutrient contribution of a HF in children with FPIGA. Children, who are not on a HF and without a VMS, are at increased risk of low intakes in particular vitamin D and zinc. Further studies need to be performed, to assess whether dietary intake translates into actual biological deficiencies