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41.
Tseng  William W.  Swallow  Carol J.  Strauss  Dirk C.  Bonvalot  Sylvie  Rutkowski  Piotr  Ford  Samuel J.  Gonzalez  Ricardo J.  Gladdy  Rebecca A.  Gyorki  David E.  Fairweather  Mark  Lee  Kyo Won  Albertsmeier  Markus  van Houdt  Winan J.  Fau  Magalie  Nessim  Carolyn  Grignani  Giovanni  Cardona  Kenneth  Quagliuolo  Vittorio  Grignol  Valerie  Farma  Jeffrey M.  Pennacchioli  Elisabetta  Fiore  Marco  Hayes  Andrew  Tzanis  Dimitri  Skoczylas  Jacek  Almond  Max L.  Mullinax  John E.  Johnston  Wendy  Snow  Hayden  Haas  Rick L.  Callegaro  Dario  Smith  Myles J.  Bouhadiba  Toufik  Desai  Anant  Voss  Rachel  Sanfilippo  Roberta  Jones  Robin L.  Baldini  Elizabeth H.  Wagner  Andrew J.  Catton  Charles N.  Stacchiotti  Silvia  Thway  Khin  Roland  Christina L.  Raut  Chandrajit P.  Gronchi  Alessandro 《Annals of surgical oncology》2022,29(12):7335-7348
Annals of Surgical Oncology - Surgery is the mainstay of treatment for retroperitoneal sarcoma (RPS), but local recurrence is common. Biologic behavior and recurrence patterns differ significantly...  相似文献   
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Ecological flexibility, extended lifespans, and large brains have long intrigued evolutionary biologists, and comparative genomics offers an efficient and effective tool for generating new insights into the evolution of such traits. Studies of capuchin monkeys are particularly well situated to shed light on the selective pressures and genetic underpinnings of local adaptation to diverse habitats, longevity, and brain development. Distributed widely across Central and South America, they are inventive and extractive foragers, known for their sensorimotor intelligence. Capuchins have among the largest relative brain size of any monkey and a lifespan that exceeds 50 y, despite their small (3 to 5 kg) body size. We assemble and annotate a de novo reference genome for Cebus imitator. Through high-depth sequencing of DNA derived from blood, various tissues, and feces via fluorescence-activated cell sorting (fecalFACS) to isolate monkey epithelial cells, we compared genomes of capuchin populations from tropical dry forests and lowland rainforests and identified population divergence in genes involved in water balance, kidney function, and metabolism. Through a comparative genomics approach spanning a wide diversity of mammals, we identified genes under positive selection associated with longevity and brain development. Additionally, we provide a technological advancement in the use of noninvasive genomics for studies of free-ranging mammals. Our intra- and interspecific comparative study of capuchin genomics provides insights into processes underlying local adaptation to diverse and physiologically challenging environments, as well as the molecular basis of brain evolution and longevity.

Large brains, long lifespans, extended juvenescence, tool use, and problem solving are hallmark characteristics of great apes, and are of enduring interest in studies of human evolution (14). Similar suites of traits have arisen in other lineages, including some cetaceans, corvids and, independently, in another radiation of primates, the capuchin monkeys. Like great apes, they have diverse diets, consume and seek out high-energy resources, engage in complex extractive foraging techniques (5, 6) to consume difficult-to-access invertebrates and nuts (6), and have an extended lifespan, presently recorded up to 54 y in captivity (7, 8). While they do not show evidence of some traits linked with large brain size in humans (e.g., human-like social networks and cultural and technological transmission from older to younger groupmates), their propensity for tool use and their ecological flexibility may have contributed to their convergence with the great apes (9), offering opportunities for understanding the evolution of key traits via the comparative method (1012). Similar approaches have revealed positive selection on genes related to brain size and long lives in great apes and other mammals (13, 14), but our understanding of the genetic underpinnings of these traits remains far from complete.Capuchins also offer excellent opportunities to study local adaptation to challenging seasonal biomes. They occupy diverse habitats, including rainforests and, in the northern extent of their range, tropical dry forests. Particular challenges of the tropical dry forest are staying hydrated during the seasonally prominent droughts, high temperatures in the absence of foliage, and coping metabolically with periods of fruit dearth (Fig. 1). The long-term study of white-faced capuchins (Cebus imitator) occupying these seasonal forests has demonstrated that high infant mortality rates accompany periods of intense drought, illustrating the strength of this selective pressure (15). Furthermore, the seasonally low abundance of fruit is associated with muscular wasting and low circulating levels of urinary creatinine among these capuchins (16). Additionally, the sensory challenges of food search in dry versus humid biomes are also distinct. Odor detection and propagation is affected by temperature and humidity (17), and color vision is hypothesized to be adaptive in the search for ripe fruits and young reddish leaves against a background of thick, mature foliage (18), which is absent for long stretches in dry deciduous forests. The behavioral plasticity of capuchins is widely acknowledged as a source of their ability to adapt to these dramatically different habitats (1921). However, physiological processes, including water balance and metabolic adaptations to low caloric intake, and sensory adaptations to food search, are also anticipated to be targets of natural selection, as seen in other mammals (2224). Understanding population-level differences between primates inhabiting different biomes, contextualized by their demographic history, genomic diversity, and historical patterns of migration, will generate new insights.Open in a separate windowFig. 1.SSR during wet (Left) and dry (Center) seasons. (Right) Map of sampling locations in Costa Rica. The two northern sites, SSR and Cañas, have tropical dry-forest biomes, whereas the two southern sites, Quepos and Manuel Antonio, are tropical wet forests. Photos courtesy of A.D.M. Drawing of white-faced capuchin monkey by Alejandra Tejada-Martinez; map courtesy of Eric Gaba–Wikimedia Commons user: Sting.Unfortunately, high-quality biological specimens from wild capuchins are not readily available. As is the case with most of the world’s primates, many of which are rare or threatened (25), this has limited the scope of questions about their biology that can be answered. Although recent advances in noninvasive genomics have allowed for the sequencing of partial genomes by enriching the proportion of endogenous DNA in feces (2629), it has not yet been feasible to sequence whole genomes from noninvasive samples at high coverage; this has limited the extent to which noninvasive samples can be used to generate genomic resources for nonmodel organisms, such as capuchins.Toward identifying the genetic underpinnings of local adaptation to seasonally harsh environments, large brains, and long lifespans, we assembled and annotated a reference genome of C. imitator (SI Appendix, Table S1). Additionally, we sequenced the genomes of individuals inhabiting two distinct environments in Costa Rica: Lowland evergreen rainforest (southern population) and lowland tropical dry forest (northern population). We conducted high-coverage resequencing (10× to 47×) for 10 of these individuals, and sequenced an additional 13 at low-coverage (0.1× to 4.4×). Importantly, to facilitate the population-wide analyses without the need for potentially harmful invasive sampling of wild primates, we developed a method for minimally biased, whole-genome sequencing of fecal DNA using fluorescence-activated cell sorting (fecalFACS) that we used to generate both high- and low-coverage genomes (Fig. 2). With these genomes, we assess the genetic underpinnings of capuchin-specific biology and adaptation in a comparative framework. First, we scanned the high-coverage genomes (six from the northern dry forest and four from the southern rainforest) for regions exhibiting population specific divergence to assess the extent of local adaptation to dry forest and rainforest environments. We examine how genes related to water balance, metabolism, muscular wasting, and chemosensation have diverged between populations. Second, we conduct an analysis of positive selection on the white-faced capuchin genome through codon-based models of evolution and enrichment tests focusing on genes that may underlie brain development and lifespan. Third, we identify the population structure, genomic diversity, and demographic history of the species using a mixture of traditional and noninvasive fecalFACS genomes (n = 23).Open in a separate windowFig. 2.Mapping percentages of sequencing reads from RNAlater preserved fecal DNA libraries prepared with FACS for (A) all samples (box-plot elements: center line, median; box limits, upper and lower quartiles; whiskers, 1.5× interquartile range; points, outliers), and (B) individual libraries. (C) Increase in mapping rate for RNAlater preserved samples. (D) Relationship between mapped read duplication and number of cells with LOESS smoothing. The duplication rate decreases sharply once a threshold of about 1,000 cells is reached.  相似文献   
43.
We describe a Sicilian family presenting a recessive form of hypercholesterolemia harboring a mutation of the autosomal recessive hypercholesterolemia (ARH) gene. In two of the three sibs, a 26-year-old male and a 22-year-old female, a severe hypercholesterolemia was diagnosed with very high levels of plasma cholesterol (15.9 and 12.2 mmol/l, respectively); tendon xanthomatas and xanthelasms were present and in the male proband was documented a diffuse coronary atherosclerotic disease with a rapid and fatal progression. Both the parents had normal or slightly increased levels of plasma cholesterol. All causes of secondary hypercholesterolemia were ruled out as well as an involvement of the LDL receptor or apoB genes. Beta-Sitosterol plasma levels were in the normal range. Cultured fibroblasts from skin biopsy from parents and the two probands displayed a normal ability to bind and degrade 125I-LDL. Direct sequencing of ARH gene demonstrated the presence of a 432insA mutation in homozygosis in the two probands; parents were heterozygotes for the same mutation. This mutation is the first report of a mutation of the ARH gene responsible for recessive forms of hypercholesterolemia in Sicily.  相似文献   
44.
For many animal taxa, the extent to which phylogeny can account for the form of species' social systems has seldom been investigated formally. A quantitative phylogenetic analysis of social systems in the order Primates reveals that social organization may be strongly conserved in some lineages, even in the face of considerable ecological variability. This result has important implications for efforts to understand the evolution of animal societies and for attempts to reconstruct the social organization of early humans.  相似文献   
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Retinal stem cell culture has become a powerful research tool, but it requires reliable methods to obtain high‐quality images of living and fixed cells. This study describes a procedure for using phase contrast microscopy to obtain three‐dimensional (3‐D) images for the study of living cells by photographing a living cell in a culture dish from bottom to top, as well as a procedure to increase the quality of scanning electron micrographs and laser confocal images. The procedure may also be used to photograph clusters of neural stem cells, and retinal explants with vigorous axonal growth. In the case of scanning electron microscopy and laser confocal images, a Gaussian procedure is applied to the original images. The methodology allows for the creation of anaglyphs and video reconstructions, and provides high‐quality images for characterizing living cells or tissues, fixed cells or tissues, or organs observed with scanning electron and laser confocal microscopy. Its greatest advantage is that it is easy to obtain good results without expensive equipment. The procedure is fast, precise, simple, and offers a strategic tool for obtaining 3‐D reconstructions of cells and axons suitable for easily determining the orientation and polarity of a specimen. It also enables video reconstructions to be created, even of specimens parallel to the plastic base of a tissue culture dish, It is also helpful for studying the distribution and organization of living cells in a culture, as it provides the same powerful information as optical tomography, which most confocal microscopes cannot do on sterile living cells. Anat Rec, 297:770–780, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
50.
The first 100 consecutive patients undergoing isolated coronary artery bypass surgery in 1975 were evaluated with respect to the incidence of operative risk factors and outcome. When compared with an identically selected group from 1985, there was significant worsening of the preoperative condition over the decade with regard to mean age (p less than 0.0005), presence of congestive heart failure (p less than 0.05), left ventricular dysfunction (p less than 0.05), severity of coronary artery disease (p less than 0.001) and incidence of emergency operation (p less than 0.05). More patients in 1985 had associated medical diseases such as diabetes (p less than 0.01) and chronic lung disease (p less than 0.005). There was an increase in the occurrence of vascular diseases (hypertension, renal dysfunction, peripheral vascular and cerebrovascular disease) (p less than 0.05). Overall operative mortality increased from 1 to 8% (p less than 0.05) over the decade. Despite the deterioration in the clinical profile of the patient undergoing coronary bypass surgery, elective procedures were still performed with low mortality. The significant increase in overall mortality was chiefly in patients undergoing emergency operation (p less than 0.05). There were also increases in operative morbidity including low output syndrome (p less than 0.01) and respiratory (p less than 0.005) and neurologic (p = 0.06) complications.  相似文献   
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