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991.
992.
Leong RW Nguyen NQ Meredith CG Al-Sohaily S Kukic D Delaney PM Murr ER Yong J Merrett ND Biankin AV 《Gastroenterology》2008,135(6):1870-1876
993.
López-Meneses M Alfonso F Fernández-Ortíz A Escaned J Flores A García P Arias J Sabaté M Hernández R Bañuelos C Macaya C 《The Journal of invasive cardiology》2002,14(5):273-276
This report describes a patient with progressive angina and a giant coronary aneurysm in the right coronary artery. Percutaneous treatment was performed using a novel technique consisting of implantation of a long stent that provided scaffolding or bridge for the subsequent implantation of two polytetrafluoroethylene-covered stents. Complete closure of the aneurysm was successfully achieved. In the angiogram performed 3 months later for recurrent angina, a localized narrowing at the distal stent edge (corresponding to severe underexpansion of the stent struts on intravascular ultrasound) was observed. This was successfully treated with balloon angioplasty. The technical details of this new technique are described. 相似文献
994.
María Martínez García Pablo Trincado Aznar Leticia Pérez Fernández Isabel Azcona Monreal María Elena López Alaminos Javier Acha Pérez Ramón Albero Gamboa 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2019,39(1)
Introduction
Both dietary restriction of sodium chloride (NaCl) and treatment with thiazides have been used in hypercalciuric patients.Objectives
To calculate regular salt intake and investigate the correlation between natriuresis and urinary calcium with usual diet (B) and after changing the amount of NaCl intake and administration of thiazides.Material and methods
Nineteen healthy young individuals had their diet replaced by 2 l of Nutrison® Low Sodium (500 mg sodium/day) daily for two days. Then, 5 g of NaCl were added every two days («5», «10» and «15»), administering 50 mg (H50) and 100 mg (H100) of Higroton® on the last two days. Blood sodium, plasma renin activity (PRA) and aldosterone were determined in venous blood samples, as were urinary sodium and calcium. Statistical analysis: Wilcoxon t-test and the Pearson linear correlation were calculated.Results
Urinary Na (mEq/24 h): 210.3 ± 87.6 («B»); 42.7 ± 20.4 («5»); 135.5 ± 50.6 («10»); 225.5 ± 56.7 («15»). Urinary calcium (mg/24 h): 207.8 ± 93.6 («B»); 172.8 ± 63.1 («5»); 206.2 ± 87.7 («10»); 227.4 ± 84.1 («15»). A positive correlation was observed between natriuresis and urinary calcium in «10» (r = 0.47) and «15» (r = 0.67). After Higroton®, natriuresis: 232.3 ± 50.7; 377 ± 4 (H50); 341.1 ± 68.4 (H100); Ca in urine: 209.8 ± 57.4; 213.2 ± 67.6 (H50); 159.1 ± 52.2 (H100).Conclusions
Salt intake in the population studied was estimated to be 14.9 ± 4.9 g/day with a positive correlation found between sodium and calcium urine output with daily intakes of 11.25 and 16.25 g of salt. With the usual intake, for each gram of salt, urinary calcium increased by 5.46 mg/24 h and with 100 mg of Higroton® it decreased by 50.7 mg/24 h. These data could be useful for the management of patients with excretory hypercalciuria or hypoparathyroidism. 相似文献995.
Joseph D. Orkin Michael J. Montague Daniela Tejada-Martinez Marc de Manuel Javier del Campo Saul Cheves Hernandez Anthony Di Fiore Claudia Fontsere Jason A. Hodgson Mareike C. Janiak Lukas F. K. Kuderna Esther Lizano Maria Pia Martin Yoshihito Niimura George H. Perry Carmen Soto Valverde Jia Tang Wesley C. Warren Joo Pedro de Magalhes Shoji Kawamura Toms Marqus-Bonet Roman Krawetz Amanda D. Melin 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(7)
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 (1–4). 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 (10–12). 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 (19–21). 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 (22–24). 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 (26–29), 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
996.
Sandra V. NAVARRA Anne‐Annette RASO Juan Javier LICHAUCO Perry P. TAN 《International journal of rheumatic diseases》2006,9(2):150-156
Aim: To describe the clinical experience with infliximab among Filipino patients with rheumatic diseases, specifically disease indications, dose regimens, clinical response, and adverse events. Methods: We reviewed the data on Filipino patients who were given infliximab by rheumatologists for a rheumatic disease indication. The case report form included demographic profile, underlying rheumatic disease, comorbidities, concurrent medications, dose and frequency of infliximab, physicians’ assessment of clinical response, and adverse events. The frequency of doses, intervals between doses, and discontinuation status were recorded. Results: Included were 64 patients (35 females), with a mean age of 44 years. Most (41%) had rheumatoid arthritis, followed by psoriasis/psoriatic arthritis (31.2%) and ankylosing spondylitis (17.2%). Average disease duration from diagnosis to initiation of infliximab therapy was 7.6 years ± 6.7 SD. Among 35 patients, the interval between maintenance infusions ranged from 6 to 13.6 weeks, with a mean of 8.27 weeks. Clinical response was good to excellent in more than 80% of patients. Discontinuation rate was 10.9% and 28.1% at 3 and 12 months, respectively. Infusion‐related adverse events were mild and transient, and 14 (21.8%) cases of infection resolved with appropriate therapy. Infliximab was temporarily withheld in five (7.8%) patients with active tuberculosis. Summary: These findings substantiate the superior clinical efficacy of infliximab and manageable adverse events among Filipinos with rheumatic diseases. It also demonstrates dose regimens in clinical practice in a third world setting with limited resources. 相似文献
997.
998.
González de Requena D Gallego O de Mendoza C Corral A Jiménez-Nácher I Soriano V 《AIDS research and human retroviruses》2003,19(6):457-459
Virological failure under protease inhibitor (PI)-based antiretroviral regimens is often not explained by the selection of resistance mutations. The role of low indinavir (IDV) plasma levels in treatment failure was assessed in 46 subjects experiencing early virological failure to a first-line IDV-containing triple combination. Overall, 69% of patients showed subtherapeutic IDV plasma levels (it was not detected at all in 75% of them). Subjects with detectable but suboptimal IDV levels developed more IDV resistance mutations. Thus, drug monitoring may be useful to assess treatment adherence and risk of drug resistance in early virological failures. This information may be crucial for choosing the most appropriate rescue intervention. 相似文献
999.
Beate Rieblinger Hicham Sid Denise Duda Tarik Bozoglu Romina Klinger Antonina Schlickenrieder Kamila Lengyel Krzysztof Flisikowski Tatiana Flisikowska Nina Simm Alessandro Grodziecki Carolin Perleberg Andrea Bhr Lucie Carrier Mayuko Kurome Valeri Zakhartchenko Barbara Kessler Eckhard Wolf Lutz Kettler Harald Luksch Ibrahim T. Hagag Daniel Wise Jim Kaufman Benedikt B. Kaufer Christian Kupatt Angelika Schnieke Benjamin Schusser 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
Genetically modified animals continue to provide important insights into the molecular basis of health and disease. Research has focused mostly on genetically modified mice, although other species like pigs resemble the human physiology more closely. In addition, cross-species comparisons with phylogenetically distant species such as chickens provide powerful insights into fundamental biological and biomedical processes. One of the most versatile genetic methods applicable across species is CRISPR-Cas9. Here, we report the generation of transgenic chickens and pigs that constitutively express Cas9 in all organs. These animals are healthy and fertile. Functionality of Cas9 was confirmed in both species for a number of different target genes, for a variety of cell types and in vivo by targeted gene disruption in lymphocytes and the developing brain, and by precise excision of a 12.7-kb DNA fragment in the heart. The Cas9 transgenic animals will provide a powerful resource for in vivo genome editing for both agricultural and translational biomedical research, and will facilitate reverse genetics as well as cross-species comparisons.Chickens and pigs are the most important livestock species worldwide. They are not only important sources of food, but also valuable models for evolutionary biology and biomedical science. Pigs share a high anatomical and physiological similarity with humans and are an important species for translational biomedical research, for example, in the areas of cancer, diabetes, neurodegenerative, and cardiovascular diseases (1–3). They also resemble the human pathophenotype more closely than rodents. For example, pig models for familial adenomatous polyposis (FAP) develop polyps in the large intestine as observed in human patients (4), whereas mouse FAP models develop them in the small intestine (5). In contrast to mammals, chickens are phylogenetically distant vertebrates from humans, but they were instrumental in the field of developmental biology due to the easy access to the embryonated egg. They are used for studying neurological and cardiovascular functions (6–8) and provided key findings in B cell development and graft versus host responses (9–11). Genetically modified livestock species also hold great promise for agriculture by offering new approaches for disease control, such as genome-edited pigs resistant to Porcine Reproductive and Respiratory Syndrome or Avian Leucosis Virus (ALV)-resistant chickens (12–15).Due to the lack of fully functional embryonic stem cells, genetic engineering in pigs and chickens has been a laborious, inefficient, and time-consuming procedure (16). The generation of pigs with precise germline modifications required gene targeting in somatic cells followed by somatic cell nuclear transfer. This also is not practical in chickens, where precise alteration of the genome only became possible with recent improvements in the cultivation and manipulation of germline-competent primordial germ cells (PGCs) (17–19). These modified PGCs can be injected into the blood vessel system of stage 13 to 15 (Hamburger−Hamilton [HH]) embryos to produce germline chimeras and, by further breeding, genetically modified chickens.With the advent of synthetic endonucleases such as CRISPR-Cas9 efficiency of targeted germline modification has improved in both species (20–23). It still requires the generation and breeding of new founder lines, which is time consuming in large animals. To circumvent the need for generating germline-modified animals, attempts have been made to carry out genome editing directly in specific organs or tissues (24–27). But this has been hampered by the need to deliver both Cas9 and the required guide RNA (gRNA) and by the limited cargo capacity of viral vectors. To bypass this drawback, Cas9 transgenic mice have been generated, requiring delivery of only the respective gRNAs (28).Here, we describe the generation of both Cas9 transgenic pigs and chickens that ubiquitously express Cas9 endonuclease and provide proof of its function in vitro and in vivo. These animals provide an innovative and efficient model for in vivo genome editing to assess gene function in health and disease. 相似文献
1000.
Karandikar NJ Kroft SH Yegappan S Rogers BB Aquino VM Lee KM Kumar V Guenaga FJ Jaffe ES Douek DC McKenna RW 《Blood》2004,104(7):2007-2009
Familial hemophagocytic lymphohistiocytosis (FHL) is an inherited, fatal disorder of infancy. We report here a 17-day-old female infant who presented with high fever, hepatosplenomegaly, hypertriglyceridemia, hypofibrinogenemia, thrombocytopenia, and liver failure. Leukocytosis was detected with circulating "atypical" lymphoid cells. Flow cytometric studies revealed expanded subpopulations of CD8+ T cells with unusual immunophenotypic features, including a subset that lacked CD5 expression. A liver biopsy showed hemophagocytic lymphohistiocytosis with exuberant infiltrates of CD8+ T cells that lacked perforin. Mutational studies revealed a 666C-->A (H222Q) missense mutation in the perforin gene. T-cell receptor studies on flow-sorted T-cell subpopulations revealed no evidence of monoclonality. Analysis of T-cell receptor excision circle levels indicated long proliferative history in the aberrant CD8+ T-cell subsets. This case provides an instructive example of uncontrolled reactive proliferation of CD8+ T cells in FHL, resulting in atypical morphology and unusual immunophenotypic features that might suggest malignancy in other clinical settings. 相似文献