Fourier Magnetic Imaging with Nanoscale Resolution and Compressed Sensing Speed-up using Electronic Spins in Diamond

Optically-detected magnetic resonance using Nitrogen Vacancy (NV) color centres in diamond is a leading modality for nanoscale magnetic field imaging, as it provides single electron spin sensitivity, three-dimensional resolution better than 1 nm, and applicability to a wide range of physical and biological samples under ambient conditions. To date, however, NV-diamond magnetic imaging has been performed using real space techniques, which are either limited by optical diffraction to 250 nm resolution or require slow, point-by-point scanning for nanoscale resolution, e.g., using an atomic force microscope, magnetic tip, or super-resolution optical imaging. Here we introduce an alternative technique of Fourier magnetic imaging using NV-diamond. In analogy with conventional magnetic resonance imaging (MRI), we employ pulsed magnetic field gradients to phase-encode spatial information on NV electronic spins in wavenumber or k-space followed by a fast Fourier transform to yield real-space images with nanoscale resolution, wide field-of-view (FOV), and compressed sensing speed-up.Comment: 31 pages, 10 figure

DNA Methylation of the ABO Promoter Underlies Loss of ABO Allelic Expression in a Significant Proportion of Leukemic Patients

Background: Loss of A, B and H antigens from the red blood cells of patients with myeloid malignancies is a frequent occurrence. Previously, we have reported alterations in ABH antigens on the red blood cells of 55% of patients with myeloid malignancies. Methodology/Principal Findings: To determine the underlying molecular mechanisms of this loss, we assessed ABO allelic expression in 21 patients with ABH antigen loss previously identified by flow cytometric analysis as well as an additional 7 patients detected with ABH antigen changes by serology. When assessing ABO mRNA allelic expression, 6/12 (50%) patients with ABH antigen loss detected by flow cytometry and 5/7 (71%) of the patients with ABH antigen loss detected by serology had a corresponding ABO mRNA allelic loss of expression. We examined the ABO locus for copy number and DNA methylation alterations in 21 patients, 11 with loss of expression of one or both ABO alleles, and 10 patients with no detectable allelic loss of ABO mRNA expression. No loss of heterozygosity (LOH) at the ABO locus was observed in these patients. However in 8/11 (73%) patients with loss of ABO allelic expression, the ABO promoter was methylated compared with 2/10 (20%) of patients with no ABO allelic expression loss (P = 0.03). Conclusions/Significance: We have found that loss of ABH antigens in patients with hematological malignancies is associated with a corresponding loss of ABO allelic expression in a significant proportion of patients. Loss of ABO allelic expression was strongly associated with DNA methylation of the ABO promoter.Tina Bianco-Miotto, Damian J. Hussey, Tanya K. Day, Denise S. O'Keefe and Alexander Dobrovi

Reliability of the Marlowe-Crowne social desirability scale in Ethiopia, Kenya, Mozambique, and Uganda

<p>Abstract</p> <p>Background</p> <p>Studies of HIV often use self-reported surveys to measure sexual knowledge, attitudes, and practices. However, the self-reported data are vulnerable to social desirability (SD), a propensity of individuals to report favorable responses. The Marlowe-Crowne Social Desirability Scale (MC-SDS) was developed as a measure of the effect of social desirability, but it has not been adapted for or used in Africa. This study aimed to apply the MC-SDS nested in an HIV behavioral intervention program and to measure its reliability in four African countries.</p> <p>Methods</p> <p>The MC-SDS was adapted based on consultations with local stakeholders and pilot tested in Ethiopia, Kenya, Mozambique, and Uganda. Trained interviewers administered the modified 28-item MC-SDS survey to 455 men and women (ages 15-24 years). The scores for the social desirability scales were calculated for all participants. An analysis of the internal consistency of responses was conducted using the Cronbach's α coefficient. Acceptable internal consistency was defined as an α coefficient of ≥ 0.70.</p> <p>Results</p> <p>Mean social desirability scores ranged from a low of 15.7 in Kenya to a high of 20.6 in Mozambique. The mean score was 17.5 for Uganda and 20.6 for Mozambique. The Cronbach's α coefficients were 0.63 in Kenya, 0.66 in Mozambique, 0.70 in Uganda, and 0.80 in Ethiopia.</p> <p>Conclusions</p> <p>The MC-SDS can be effectively adapted and implemented in sub-Saharan Africa. The reliability of responses in these settings suggest that the MC-SDS could be a useful tool for capturing potential SD in surveys of HIV related risk behaviors.</p

Paroxysmal autonomic instability with dystonia in a patient with tuberculous meningitis: a case report

<p>Abstract</p> <p>Introduction</p> <p>This case report describes an extremely rare combination of paroxysmal autonomic instability with dystonia and tuberculous meningitis. Paroxysmal autonomic instability with dystonia is normally associated with severe traumatic brain injury.</p> <p>Case presentation</p> <p>A 69-year-old man of Indonesian descent was initially suspected of having a community-acquired pneumonia, which was seen on chest X-ray and computed tomography of the chest. However, a bronchoscopy showed no abnormalities. He was treated with amoxicillin-clavulanic acid in combination with ciprofloxacin. However, nine days after admission he was disorientated and complained of headache. Neurological examination revealed no further abnormalities. A lumbar puncture revealed no evidence of meningitis. He was then transferred to our hospital. At that time, initial cultures of bronchial fluid for <it>Mycobacterium tuberculosis </it>turned positive, as well as polymerase chain reaction for <it>Mycobacterium tuberculosis</it>. Later, during his stay in our intensive care unit, he developed periods with hypertension, sinus tachycardia, excessive transpiration, decreased oxygen saturation with tachypnea, pink foamy sputum, and high fever. This constellation of symptoms was accompanied by dystonia in the first days. These episodes lasted approximately 30 minutes and improved after administration of morphine, benzodiazepines or clonidine. Magnetic resonance imaging showed an abnormal signal in the region of the hippocampus, thalamus and the anterior parts of the lentiform nucleus and caudate nucleus.</p> <p>Conclusions</p> <p>In patients with (tuberculous) meningitis and episodes of extreme hypertension and fever, paroxysmal autonomic instability with dystonia should be considered.</p

Noninvasive ventilation in COVID-19 patients aged ≥ 70 years-a prospective multicentre cohort study.

BACKGROUND Noninvasive ventilation (NIV) is a promising alternative to invasive mechanical ventilation (IMV) with a particular importance amidst the shortage of intensive care unit (ICU) beds during the COVID-19 pandemic. We aimed to evaluate the use of NIV in Europe and factors associated with outcomes of patients treated with NIV. METHODS This is a substudy of COVIP study-an international prospective observational study enrolling patients aged ≥ 70 years with confirmed COVID-19 treated in ICU. We enrolled patients in 156 ICUs across 15 European countries between March 2020 and April 2021.The primary endpoint was 30-day mortality. RESULTS Cohort included 3074 patients, most of whom were male (2197/3074, 71.4%) at the mean age of 75.7 years (SD 4.6). NIV frequency was 25.7% and varied from 1.1 to 62.0% between participating countries. Primary NIV failure, defined as need for endotracheal intubation or death within 30 days since ICU admission, occurred in 470/629 (74.7%) of patients. Factors associated with increased NIV failure risk were higher Sequential Organ Failure Assessment (SOFA) score (OR 3.73, 95% CI 2.36-5.90) and Clinical Frailty Scale (CFS) on admission (OR 1.46, 95% CI 1.06-2.00). Patients initially treated with NIV (n = 630) lived for 1.36 fewer days (95% CI - 2.27 to - 0.46 days) compared to primary IMV group (n = 1876). CONCLUSIONS Frequency of NIV use varies across European countries. Higher severity of illness and more severe frailty were associated with a risk of NIV failure among critically ill older adults with COVID-19. Primary IMV was associated with better outcomes than primary NIV. Clinical Trial Registration NCT04321265 , registered 19 March 2020, https://clinicaltrials.gov

Neuroinflammation, Mast Cells, and Glia: Dangerous Liaisons

The perspective of neuroinflammation as an epiphenomenon following neuron damage is being replaced by the awareness of glia and their importance in neural functions and disorders. Systemic inflammation generates signals that communicate with the brain and leads to changes in metabolism and behavior, with microglia assuming a pro-inflammatory phenotype. Identification of potential peripheral-to-central cellular links is thus a critical step in designing effective therapeutics. Mast cells may fulfill such a role. These resident immune cells are found close to and within peripheral nerves and in brain parenchyma/meninges, where they exercise a key role in orchestrating the inflammatory process from initiation through chronic activation. Mast cells and glia engage in crosstalk that contributes to accelerate disease progression; such interactions become exaggerated with aging and increased cell sensitivity to stress. Emerging evidence for oligodendrocytes, independent of myelin and support of axonal integrity, points to their having strong immune functions, innate immune receptor expression, and production/response to chemokines and cytokines that modulate immune responses in the central nervous system while engaging in crosstalk with microglia and astrocytes. In this review, we summarize the findings related to our understanding of the biology and cellular signaling mechanisms of neuroinflammation, with emphasis on mast cell-glia interactions

The NlpD Lipoprotein Is a Novel Yersinia pestis Virulence Factor Essential for the Development of Plague

Yersinia pestis is the causative agent of plague. Previously we have isolated an attenuated Y. pestis transposon insertion mutant in which the pcm gene was disrupted. In the present study, we investigated the expression and the role of pcm locus genes in Y. pestis pathogenesis using a set of isogenic surE, pcm, nlpD and rpoS mutants of the fully virulent Kimberley53 strain. We show that in Y. pestis, nlpD expression is controlled from elements residing within the upstream genes surE and pcm. The NlpD lipoprotein is the only factor encoded from the pcm locus that is essential for Y. pestis virulence. A chromosomal deletion of the nlpD gene sequence resulted in a drastic reduction in virulence to an LD50 of at least 107 cfu for subcutaneous and airway routes of infection. The mutant was unable to colonize mouse organs following infection. The filamented morphology of the nlpD mutant indicates that NlpD is involved in cell separation; however, deletion of nlpD did not affect in vitro growth rate. Trans-complementation experiments with the Y. pestis nlpD gene restored virulence and all other phenotypic defects. Finally, we demonstrated that subcutaneous administration of the nlpD mutant could protect animals against bubonic and primary pneumonic plague. Taken together, these results demonstrate that Y. pestis NlpD is a novel virulence factor essential for the development of bubonic and pneumonic plague. Further, the nlpD mutant is superior to the EV76 prototype live vaccine strain in immunogenicity and in conferring effective protective immunity. Thus it could serve as a basis for a very potent live vaccine against bubonic and pneumonic plague

Defending the genome from the enemy within:mechanisms of retrotransposon suppression in the mouse germline

The viability of any species requires that the genome is kept stable as it is transmitted from generation to generation by the germ cells. One of the challenges to transgenerational genome stability is the potential mutagenic activity of transposable genetic elements, particularly retrotransposons. There are many different types of retrotransposon in mammalian genomes, and these target different points in germline development to amplify and integrate into new genomic locations. Germ cells, and their pluripotent developmental precursors, have evolved a variety of genome defence mechanisms that suppress retrotransposon activity and maintain genome stability across the generations. Here, we review recent advances in understanding how retrotransposon activity is suppressed in the mammalian germline, how genes involved in germline genome defence mechanisms are regulated, and the consequences of mutating these genome defence genes for the developing germline