Comments on gauge-invariance in cosmology

We revisit the gauge issue in cosmological perturbation theory, and highlight its relation to the notion of covariance in general relativity. We also discuss the similarities and differences of the covariant approach in perturbation theory to the Bardeen or metric approach in a non-technical fashion.Comment: 7 pages, 1 figure, revtex4; v3: minor changes, typos corrected, discussion extended; v4: typos corrected, corresponding to published versio

Implantable Doppler Probe as a Vascular Monitoring Device in Kidney Transplant Patients: Investigation of Use at a Single Center.

OBJECTIVES: Vascular complications account for 30% to 35% of total kidney grafts lost during the first 3 months posttransplant. Early detection of vascular complications allows an opportunity for prompt intervention, which is critical to reducing graft loss. In this study, we evaluated the usefulness of an implantable Doppler probe as a vascular monitoring device in kidney transplant patients. MATERIALS AND METHODS: An implantable Doppler probe is used intermittently for postoperative monitoring of kidney transplant patients at our center. In this retrospective study, we analyzed prospectively maintained medical data in which we compared clinical outcomes of kidney transplant recipients who had postoperative implantable Doppler probe monitoring versus standard care clinical observation. Between January 2016 and October 2021, 324 kidney transplant patients were seen at our center. Patients were divided into 2 groups: group 1 (n = 194; 60%) included kidney transplant recipients with postoperative implantable Doppler probe monitoring and group 2 (n = 129; 40%) included kidney transplant recipients with standard care clinical observation. We compared number of vascular complications, number of departmental ultrasonographic scans required posttransplant, and graftloss at 3 months between the 2 groups. RESULTS: Vascular complications were identified in 13.5% of total patients, with graft loss identified in 2.1%. Both groups were similar in demographical characteristics. Group 1 had more vascular complications (17.5% vs 9.3%; relative risk = 1.88), fewer ultrasonographic scans during the first 24 hours posttransplant (71.1% vs 83.7%; relative risk = 0.84), and lower graft loss (1.5% vs 3.1%; relative risk = 0.48) than group 2. All probes were removed safely after 72 hours, and no complications related to the device were reported. CONCLUSIONS: The monitoring device may be used as an additional adjunct for graft monitoring in kidney transplant patients. Further controlled studies are warranted to evaluate this device in clinical practice

A simplified structure for the second order cosmological perturbation equations

Increasingly accurate observations of the cosmic microwave background and the large scale distribution of galaxies necessitate the study of nonlinear perturbations of Friedmann-Lemaitre cosmologies, whose equations are notoriously complicated. In this paper we present a new derivation of the governing equations for second order perturbations within the framework of the metric-based approach that is minimal, as regards amount of calculation and length of expressions, and flexible, as regards choice of gauge and stress-energy tensor. Because of their generality and the simplicity of their structure our equations provide a convenient starting point for determining the behaviour of nonlinear perturbations of FL cosmologies with any given stress-energy content, using either the Poisson gauge or the uniform curvature gauge.Comment: 30 pages, no figures. Changed title to the one in published version and some minor changes and addition

Potential Role of Ultrafine Particles in Associations between Airborne Particle Mass and Cardiovascular Health

Numerous epidemiologic time-series studies have shown generally consistent associations of cardiovascular hospital admissions and mortality with outdoor air pollution, particularly mass concentrations of particulate matter (PM) ≤2.5 or ≤10 μm in diameter (PM(2.5), PM(10)). Panel studies with repeated measures have supported the time-series results showing associations between PM and risk of cardiac ischemia and arrhythmias, increased blood pressure, decreased heart rate variability, and increased circulating markers of inflammation and thrombosis. The causal components driving the PM associations remain to be identified. Epidemiologic data using pollutant gases and particle characteristics such as particle number concentration and elemental carbon have provided indirect evidence that products of fossil fuel combustion are important. Ultrafine particles < 0.1 μm (UFPs) dominate particle number concentrations and surface area and are therefore capable of carrying large concentrations of adsorbed or condensed toxic air pollutants. It is likely that redox-active components in UFPs from fossil fuel combustion reach cardiovascular target sites. High UFP exposures may lead to systemic inflammation through oxidative stress responses to reactive oxygen species and thereby promote the progression of atherosclerosis and precipitate acute cardiovascular responses ranging from increased blood pressure to myocardial infarction. The next steps in epidemiologic research are to identify more clearly the putative PM casual components and size fractions linked to their sources. To advance this, we discuss in a companion article (Sioutas C, Delfino RJ, Singh M. 2005. Environ Health Perspect 113:947–955) the need for and methods of UFP exposure assessment

Epithelial dynamics shed light on mechanisms underlying ear canal defects

Defects in ear canal development can cause severe hearing loss as sound waves fail to reach the middle ear. Here we reveal new mechanisms that control human canal development and highlight for the first time the complex system of canal closure and reopening. These processes can be perturbed in mutant mice and in explant culture, mimicking the defects associated with canal aplasia. The more superficial part of the canal forms from an open primary canal that closes and then reopens. In contrast, the deeper part of the canal forms from an extending solid meatal plate that opens later. Closure and fusion of the primary canal was linked to loss of periderm, with failure in periderm formation in Grhl3 mutant mice associated with premature closure of the canal. Conversely, inhibition of cell death in the periderm resulted in an arrest of closure. Once closed, re-opening of the canal occurred in a wave, triggered by terminal differentiation of the epithelium. Understanding these complex processes involved in canal development sheds light on the underlying causes of canal aplasia

The Impact of Educational Intervention of HighRisk Pregnancy and HighRisk Childbirth on Knowledge, Attitude, and Behavior in Recognizing Danger Signs in Pregnancy: A Single Blind Clinical Trial

Objective: To assess the impact of additional educational interventions given to pregnant women in identifying high-risk pregnancy and high-risk childbirth by measuring changes in knowledge, attitudes and behaviors in the pregnancy and after childbirth. Methods: This study was a single blind clinical trial conducted at obstetrics out-patient clinic of Dr. Cipto Mangunkusumo Hospital, Jakarta. Total sample were 52 responders, for the 26 responders to the control group and 26 responders to the intervention group. The research instrument was a questionnaire form, which include knowledge, attitude and behaviour of a number of 48 questions. Analysis was performed using SPSS 20 with bivariate analysis. Results: We did not found significant differences in a range of age (30.65 29.38 with 1.20 0.75), education (both groups showed a high level of education) and employment for both groups. We found significant differences on knowledge, behaviour (p = 0.001 and = 0.042, respectively) on the first antenatal care compared with after childbirth. Conclusion: The educational intervention gives significant impact in attitude and behaviour. [Indones J Obstet Gynecol 2017; 5-2: 69-72] Keywords: attitude, behaviour, educational intervention, knowledg

A single residue substitution in the receptor-binding domain of H5N1 hemagglutinin is critical for packaging into pseudotyped lentiviral particles

© 2012 Tang et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Background: Serological studies for influenza infection and vaccine response often involve microneutralization and hemagglutination inhibition assays to evaluate neutralizing antibodies against human and avian influenza viruses, including H5N1. We have previously characterized lentiviral particles pseudotyped with H5-HA (H5pp) and validated an H5pp-based assay as a safe alternative for high-throughput serological studies in BSL-2 facilities. Here we show that H5-HAs from different clades do not always give rise to efficient production of H5pp and the underlying mechanisms are addressed. Methodology/Findings: We have carried out mutational analysis to delineate the molecular determinants responsible for efficient packaging of HA from A/Cambodia/40808/2005 (H5Cam) and A/Anhui/1/2005 (H5Anh) into H5pp. Our results demonstrate that a single A134V mutation in the 130-loop of the receptor binding domain is sufficient to render H5Anh the ability to generate H5Anh-pp efficiently, whereas the reverse V134A mutation greatly hampers production of H5Cam-pp. Although protein expression in total cell lysates is similar for H5Anh and H5Cam, cell surface expression of H5Cam is detected at a significantly higher level than that of H5Anh. We further demonstrate by several independent lines of evidence that the behaviour of H5Anh can be explained by a stronger binding to sialic acid receptors implicating residue 134. Conclusions: We have identified a single A134V mutation as the molecular determinant in H5-HA for efficient incorporation into H5pp envelope and delineated the underlying mechanism. The reduced binding to sialic acid receptors as a result of the A134V mutation not only exerts a critical influence in pseudotyping efficiency of H5-HA, but has also an impact at the whole virus level. Because A134V substitution has been reported as a naturally occurring mutation in human host, our results may have implications for the understanding of human host adaptation of avian influenza H5N1 virusesThis work was supported by grants from the Research Fund for the Control of Infectious Diseases of Hong Kong (RFCID#08070972), the Area of Excellence Scheme of the University Grants Committee (grant AoE/M-12/-06 of the Hong Kong Special Administrative Region, China), the French Ministry of Health, and the RESPARI project of the Institut Pasteur International Network

Measuring the effect of enhanced cleaning in a UK hospital : a prospective cross-over study

Increasing hospital-acquired infections have generated much attention over the last decade. There is evidence that hygienic cleaning has a role in the control of hospital-acquired infections. This study aimed to evaluate the potential impact of one additional cleaner by using microbiological standards based on aerobic colony counts and the presence of Staphylococcus aureus including meticillin-resistant S. aureus. We introduced an additional cleaner into two matched wards from Monday to Friday, with each ward receiving enhanced cleaning for six months in a cross-over design. Ten hand-touch sites on both wards were screened weekly using standardised methods and patients were monitored for meticillin-resistant S. aureus infection throughout the year-long study. Patient and environmental meticillin-resistant S. aureus isolates were characterised using molecular methods in order to investigate temporal and clonal relationships. Enhanced cleaning was associated with a 32.5% reduction in levels of microbial contamination at handtouch sites when wards received enhanced cleaning (P < 0.0001: 95% CI 20.2%, 42.9%). Near-patient sites (lockers, overbed tables and beds) were more frequently contaminated with meticillin-resistant S. aureus/S. aureus than sites further from the patient (P = 0.065). Genotyping identified indistinguishable strains from both handtouch sites and patients. There was a 26.6% reduction in new meticillin-resistant S. aureus infections on the wards receiving extra cleaning, despite higher meticillin-resistant S. aureus patient-days and bed occupancy rates during enhanced cleaning periods (P = 0.032: 95% CI 7.7%, 92.3%). Adjusting for meticillin-resistant S. aureus patient-days and based upon nine new meticillin-resistant S. aureus infections seen during routine cleaning, we expected 13 new infections during enhanced cleaning periods rather than the four that actually occurred. Clusters of new meticillin-resistant S. aureus infections were identified 2 to 4 weeks after the cleaner left both wards. Enhanced cleaning saved the hospital £30,000 to £70,000.Introducing one extra cleaner produced a measurable effect on the clinical environment, with apparent benefit to patients regarding meticillin-resistant S. aureus infection. Molecular epidemiological methods supported the possibility that patients acquired meticillin-resistant S. aureus from environmental sources. These findings suggest that additional research is warranted to further clarify the environmental, clinical and economic impact of enhanced hygienic cleaning as a component in the control of hospital-acquired infection

Uterine primitive neuroectodermal tumor with adenosarcoma: a case report

<p>Abstract</p> <p>Introduction</p> <p>Primitive neuroectodermal tumor of the uterus is extremely rare. They occur as either pure primitive neuroectodermal tumors or admixed with neoplasms of mullerian origin.</p> <p>Case presentation</p> <p>A case of uterine primitive neuroectodermal tumor with adenosarcoma in a 50-year-old Asian Indian woman is presented. Histologically, the neoplasm displayed perivascular pseudorosettes and occasional Homer-Wright rosettes. A strong positivity for neuronspecific enolase and synaptophysin was noted, while chromogranin and CD99 were negative. Merging imperceptibly with the neuroectodermal components were the areas of adenosarcoma.</p> <p>Conclusion</p> <p>To the best of our knowledge, this report represents the second case of a uterine primitive neuroectodermal tumor with an admixed adenosarcoma.</p