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INTRODUCTION: Although the genome is often called the blueprint of an organism, it is perhaps more accurate to describe it as a parts list composed of the various genes that may or may not be used in the different cell types of a multicellular organism. Although nearly every cell in the body has essentially the same genome, each cell type makes different use of that genome and expresses a subset of all possible genes. This has motivated efforts to characterize the molecular composition of various cell types within humans and multiple model organisms, both by transcriptional and proteomic approaches. We created a human reference atlas comprising nearly 500,000 cells from 24 different tissues and organs, many from the same donor. This atlas enabled molecular characterization of more than 400 cell types, their distribution across tissues, and tissue-specific variation in gene expression. RATIONALE: One caveat to current approaches to make cell atlases is that individual organs are often collected at different locations, collected from different donors, and processed using different protocols. Controlled comparisons of cell types between different tissues and organs are especially difficult when donors differ in genetic background, age, environmental exposure, and epigenetic effects. To address this, we developed an approach to analyzing large numbers of organs from the same individual. RESULTS: We collected multiple tissues from individual human donors and performed coordinated single-cell transcriptome analyses on live cells. The donors come from a range of ethnicities, are balanced by gender, have a mean age of 51 years, and have a variety of medical backgrounds. Tissue experts used a defined cell ontology terminology to annotate cell types consistently across the different tissues, leading to a total of 475 distinct cell types with reference transcriptome profiles. The full dataset can be explored online with the cellxgene tool. Data were collected for the bladder, blood, bone marrow, eye, fat, heart, kidney, large intestine, liver, lung, lymph node, mammary, muscle, pancreas, prostate, salivary gland, skin, small intestine, spleen, thymus, tongue, trachea, uterus, and vasculature. Fifty-nine separate specimens in total were collected, processed, and analyzed, and 483,152 cells passed quality control filtering. On a per-compartment basis, the dataset includes 264,824 immune cells, 104,148 epithelial cells, 31,691 endothelial cells, and 82,478 stromal cells. Working with live cells, as opposed to isolated nuclei, ensured that the dataset includes all mRNA transcripts within the cell, including transcripts that have been processed by the cell’s splicing machinery, thereby enabling insight into variation in alternative splicing. The Tabula Sapiens also provided an opportunity to densely and directly sample the human microbiome throughout the gastrointestinal tract. The intestines from two donors were sectioned into five regions: the duodenum, jejunum, ileum, and ascending and sigmoid colon. Each section was transected, and three to nine samples were collected from each location, followed by amplification and sequencing of the 16S ribosomal RNA gene. CONCLUSION: The Tabula Sapiens has revealed discoveries relating to shared behavior and subtle, organ-specific differences across cell types. We found T cell clones shared between organs and characterized organ-dependent hypermutation rates among B cells. Endothelial cells and macrophages are shared across tissues, often showing subtle but clear differences in gene expression. We found an unexpectedly large and diverse amount of cell type–specific RNA splice variant usage and discovered and validated many previously undefined splices. The intestinal microbiome was revealed to have nonuniform species distributions down to the 3-inch (7.62-cm) length scale. These are but a few examples of how the Tabula Sapiens represents a broadly useful reference to deeply understand and explore human biology at cellular resolution.

Molecular characterization of cell types using single-cell transcriptome sequencing is revolutionizing cell biology and enabling new insights into the physiology of human organs. We created a human reference atlas comprising nearly 500,000 cells from 24 different tissues and organs, many from the same donor. This atlas enabled molecular characterization of more than 400 cell types, their distribution across tissues, and tissue-specific variation in gene expression. Using multiple tissues from a single donor enabled identification of the clonal distribution of T cells between tissues, identification of the tissue-specific mutation rate in B cells, and analysis of the cell cycle state and proliferative potential of shared cell types across tissues. Cell type-specific RNA splicing was discovered and analyzed across tissues within an individual.

A major hypothesis for the evolution of chemical signals is that pheromones arise from non-communicative precursor compounds. However, data supporting this hypothesis are rare, primarily because the original functions of the antecedent compounds often have been lost. A notable exception, however, is the parasitoid wasp speciesLeptopilina heterotoma, whose compound (−)-iridomyrmecin is used as a defensive secretion, a cue for females to avoid competition with con- and hetero-specific females, and as the primary component of the females’ sex pheromone. To better understand the evolution of sex pheromones from defensive compounds, we examined the chemical ecology ofL. pacifica, the sister species ofL. heterotoma. Here, we show thatL. pacificaalso produces a defensive secretion containing a species-specific mixture of mostly iridoid compounds. However, the composition of the secretion is more complex than inL. heterotoma, and iridomyrmecin is only a minor component. Moreover, in contrast toL. heterotoma, conspecific female competitors were not avoided by female subjects, and a role of the iridoids in the female sex pheromone ofL. pacificacan be excluded, as only the females’ cuticular hydrocarbons (CHCs) resulted in the elicitation of courtship by males. Although closely related, the two sister species show substantial differences in the use of the defensive secretion for communicative purposes. Variation in pheromone usage in this genus still presents a conundrum, highlighting the need for additional studies to understand the selective forces shaping the evolution of pheromone composition.

The landscape of surgical training has been subject to many changes over the past 15 years. This study examines resident satisfaction, determinants of satisfaction, demographics, working hours and the teaching rate of common operations in a longitudinal fashion with the aim to identify trends, shortcomings and possible ways to improve the current training system. The Swiss Medical Association administers an annual survey to all Swiss residents to evaluate the quality of postgraduate medical training (yearly respondents: 687–825, response rate: 68–72%). Teaching rates for general surgical procedures were obtained from the Swiss association for quality management in surgery. During the study period (2003–2018), the number of surgical residents (408–655 (+61%)) and graduates in general surgery per year (42–63 (+50%)) increased disproportionately to the Swiss population. While the 52 working hour restriction was introduced in 2005 reported average weekly working hours did not decline (59.9–58.4 h (−3%)). Workplace satisfaction (6 being highest) rose from 4.3 to 4.6 (+7%). Working climate and leadership culture were the main determinants for resident satisfaction. The proportion of taught basic surgical procedures fell from 24.6 to 18.9% (−23%). The number of residents and graduates in general surgery has risen markedly. At the same time, the proportion of taught operations is diminishing. Despite the introduction of working hour restrictions, the self-reported hours never reached the limit. The low teaching rate combined with the increasing resident number represents a major challenge to the maintenance of the current training quality.

OBJECTIVES To compare the clinical outcomes of oligometastatic versus widely metastatic NPC patients. MATERIALS AND METHODS Retrospective review of 157 patients with metastatic NPC at a tertiary hospital was performed. Multivariate analysis was carried out to compare the overall and progression-free survival (OS and PFS) of these two cohorts of NPC patients. The number of organ involvement and discrete metastatic lesions associated with improved OS and PFS were ascertained. RESULTS Patients with oligometastatic NPC (single organ, less than six discrete metastatic lesions) had a better median OS than patients with widespread metastasis (24.8 versus 12.8 months, P

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Pulmonary hypertension (PH) is a heterogenous and incurable disease marked by varying degrees of pulmonary vascular remodeling. This vascular remodeling, which includes thickening of the smooth muscle layer (an early finding) and formation of occlusive neointimal lesions (a late finding) in the pulmonary arteries, is a major driver of morbidity and mortality in PH. Available PH therapies consist of vasodilators that do not specifically target lesion formation or expansion and neither prevent progression nor reverse disease. This paucity of curative treatments highlights the need for new drug discovery targeting crucial steps of artery remodeling in PH. The cell dynamics and molecular signals driving neointimal lesion formation have been difficult to elucidate as classic mouse models of PH do not develop neointima. Here, we detail the methods to generate a robust and non-genetic mouse model of PH with medial thickening and neointimal lesion formation in the pulmonary arteries, through chronic exposure to an inflammatory stimulus—house dust mite (HDM). This model rapidly generates human-like pulmonary arterial lesions following a reproducible time course, allowing scrutiny of the cellular and molecular mechanisms controlling each stage of artery remodeling. Further, we outline optimal tissue handling, sectioning, and staining methodologies for detailed quantitative analysis of artery medial thickening and neointimal lesion formation and expansion. Finally, we present a method for staged pharmacologic intervention to identify molecules and pathways required at each step of the pulmonary arterial remodeling process. The advantages of this mouse model of PH over currently available animal models are five-fold. (i) It allows the use of the full range of genetic and single cell tools available in mice to manipulate and study the process of vascular remodeling seen in human disease, including the formation of neointimal lesions in a controlled and cell specific manner. (ii) The vascular lesions develop in a stereotyped manner with predictable timing, allowing for pharmacologic manipulation at discrete stages of vessel remodeling. (iii) It is rapid, with development of PH and vascular remodeling in a timeframe of two to eight weeks. (iv) It uses simple techniques and requires neither surgery, unusual equipment, or extensive personnel training. (v) The staining and quantitation methodologies we present are a significant improvement over those currently in use in the field. We hope that dissemination of this model and the associated detailed methods will speed up the development of novel and more effective PH therapeutics. Graphic abstract: [Image: see text] Chronic perivascular inflammation induces medial thickening and neointima formation in pulmonary arteries, following a stereotyped time course, and allowing staged pharmacologic intervention during specific remodeling events, as well as quantitative assessment of vascular changes.

Mental health challenges are common during the perinatal period, particularly following pregnancy loss. This longitudinal study investigates the role of self-compassion in the mental health of perinatal women having previously experienced ( n = 45) or not having experienced ( n = 123) pregnancy loss. Archival data was utilised to compare levels of perinatal depression, psychological distress, and self-compassion for women receiving psychological therapy at session one and session six. Results indicated that both participant groups reported similar levels on all variables at baseline. There were significant increases in self-compassion and decreases in perinatal depression and psychological distress after six sessions of therapy for both groups. A regression showed changes in self-compassion following six sessions of therapy was predictive of psychological distress, particularly for women who reported pregnancy loss. Self-compassion may represent a viable intervention for psychological distress in a perinatal population particularly following pregnancy loss.

Permanently cold marine sediments are heavily influenced by increased input of iron as a result of accelerated glacial melt, weathering, and erosion. The impact of such environmental changes on microbial communities in coastal sediments is poorly understood. We investigated geochemical parameters that shape microbial community compositions in anoxic surface sediments of four geochemically differing sites (Annenkov Trough, Church Trough, Cumberland Bay, Drygalski Trough) around South Georgia, Southern Ocean. Sulfate reduction prevails in Church Trough and iron reduction at the other sites, correlating with differing local microbial communities. Within the order Desulfuromonadales, the family Sva1033, not previously recognized for being capable of dissimilatory iron reduction, was detected at rather high relative abundances (up to 5%) while other members of Desulfuromonadales were less abundant (, Facultad de Ciencias Exactas

During the COVID-19 pandemic, structural biologists have rushed to solve the structures of the 28 proteins encoded by the SARS-CoV-2 genome in order to understand the viral life cycle and enable structure-based drug design. In addition to the 200 structures from SARS-CoV previously solved, 367 structures covering 16 of the viral proteins have been released in the span of only 6 months. These structural models serve as basis for research worldwide to understand how the virus hijacks human cells, for structure-based drug design and to aid in the development of vaccines. However, errors often occur in even the most careful structure determination - and are even more common among these structures, which were solved under immense pressure. From the beginning of the pandemic, the Coronavirus Structural Taskforce has categorized, evaluated and reviewed all of these experimental protein structures in order to help downstream users and original authors. Our website also offers improved models for many key structures, which have been used by Folding@Home, OpenPandemics, the EU JEDI COVID-19 challenge, and others. Here, we describe our work for the first time, give an overview of common problems, and describe a few of these structures that have since acquired better versions in the worldwide Protein Data Bank, either from new data or as depositor re-versions using our suggested changes.

Integration and utilization of ICT in education became in demand in today’s situation as brought by the pandemic. The changes in the educational landscape led to maximization of the usage of the available digital resources. Thus, the study aimed to assess the implementation of DepEd Computerization Program in District 9 of Division of Batangas City with the end view of proposing an ICT management plan for its effective implementation in the New Normal. Specifically, it described the characteristics of elementary teachers, assessed the extent of utilization of the computer aided instruction, tested its significant relationship with the profile variables, identified the issues and concerns, and proposed an ICT management plan. The study utilized descriptive method of research with the questionnaire as main data gathering instrument supported by the FGD and interview. Respondents were 105 teachers from 11 public elementary schools in the district. Frequency, percentage, weighted mean, Cronbach alpha and Chi-square Test were the statistical tools used to treat and analyzed the data. Results revealed that 60 percent of the respondents were aged 36 years old and above, with 4-5 gadgets available for teaching, and with at least one ICT training attended. Findings indicated that the program was implemented to a moderate extent in terms of objectives, infrastructure provision, program orientation and monitoring and evaluation. Age, highest educational attainment, and number of ICT trainings were found to have some significant relationships to the extent of utilization of computer aided instruction. Internet connectivity, number of computer units, and upgrading of computer system were the common issues and concerns encountered by the elementary teachers affecting program implementation. On the latter part, the researcher proposed an ICT management plan to raise the ICT literacy of the teachers with consideration to their age and assistance in performing teaching related tasks in the New Normal.

Photoelectrodes based on CdSe nanoplatelet cryoaerogels are prepared and the charge carrier transport within these structures is investigated photoelectrochemically., Semiconductor nanoparticle based porous 3D assemblies are interesting materials for various applications in the fields of photovoltaics, catalysis, or optical sensing. For use as photoelectrodes in photoelectrochemical sensors they need to be characterised by a high porosity, a good photostability, and a high charge carrier mobility. Our work reports on the preparation of cryoaerogel photoelectrodes based on CdSe nanoplatelets and their photoelectrochemical characterisation by means of linear sweep voltammetry (LSV) and intensity modulated photocurrent spectroscopy (IMPS). The obtained open-pored cryoaerogel films were observed to produce much higher photocurrents than comparable drop-cast films. By means of IMPS, the performance differences could be linked to the occurrence of charge carrier movement, which could solely be proven for the cryoaerogels. In a proof-of-principle experiment, the potential of the prepared photoelectrodes for application in photoelectrochemical sensing was moreover demonstrated.

Deciphering the processes driving the evolution of the diverse pheromone-mediated chemical communication system of insects is a fascinating and challenging task. Understanding how pheromones have arisen has been supported by studies with the model organism Leptopilina heterotoma, a parasitoid wasp whose defensive compound (-)-iridomyrmecin also evolved as a component of the female sex pheromone and as a cue to avoid competition with other females during host search. To understand how compounds can evolve from being non-communicative to having a communicative function and to shed light on the evolution of the multi-functional use of iridomyrmecin in the genus Leptopilina, the chemical communication of two additional species, L. ryukyuensis and L. japonica, was studied. We demonstrate that in both species a species-specific mixture of iridoids is produced and emitted by wasps upon being attacked, consistent with their putative role as defensive compounds. In L. ryukyuensis these iridoids are also used by females to avoid host patches already exploited by other conspecific females. However, females of L. japonica do not avoid the odor of conspecific females during host search. We also show that the sex pheromone of female L. ryukyuensis consists of cuticular hydrocarbons (CHCs), as males showed strong courtship behavior (wing fanning) towards these compounds, but not towards the iridoid compounds. In contrast, males of L. japonica prefer their females' iridoids but CHCs also elicit some courtship behavior. The use of iridoid compounds as defensive allomones seems to be common in the genus Leptopilina, while their communicative functions appear to have evolved in a species-specific manner.