112 research outputs found
A New Approach to Measuring Distances in Dense Graphs
The problem of computing distances and shortest paths between vertices in graphs is one of the fundamental issues in graph theory. It is of great importance in many different applications, for example, transportation, and social network analysis. However, efficient shortest distance algorithms are still desired in many disciplines. Basically, the majority of dense graphs have ties between the shortest distances. Therefore, we consider a different approach and introduce a new measure to solve all-pairs shortest paths for undirected and unweighted graphs. This measures the shortest distance between any two vertices by considering the length and the number of all possible paths between them. The main aim of this new approach is to break the ties between equal shortest paths SP, which can be obtained by the Breadth-first search algorithm (BFS), and distinguish meaningfully between these equal distances. Moreover, using the new measure in clustering produces higher quality results compared with SP. In our study, we apply two different clustering techniques: hierarchical clustering and K-means clustering, with four different graph models, and for a various number of clusters. We compare the results using a modularity function to check the quality of our clustering results
Dynamic Community Detection into Analyzing of Wildfires Events
The study and comprehension of complex systems are crucial intellectual and
scientific challenges of the 21st century. In this scenario, network science
has emerged as a mathematical tool to support the study of such systems.
Examples include environmental processes such as wildfires, which are known for
their considerable impact on human life. However, there is a considerable lack
of studies of wildfire from a network science perspective. Here, employing the
chronological network concept -- a temporal network where nodes are linked if
two consecutive events occur between them -- we investigate the information
that dynamic community structures reveal about the wildfires' dynamics.
Particularly, we explore a two-phase dynamic community detection approach,
i.e., we applied the Louvain algorithm on a series of snapshots. Then we used
the Jaccard similarity coefficient to match communities across adjacent
snapshots. Experiments with the MODIS dataset of fire events in the Amazon
basing were conducted. Our results show that the dynamic communities can reveal
wildfire patterns observed throughout the year.Comment: 16 pages, 8 figure
Long-Lasting Inhibitory Effects of Fetal Liver Mesenchymal Stem Cells on T-Lymphocyte Proliferation
Human bone marrow mesenchymal stem cells (BM-MSC) are multipotent progenitor cells that have transient immunomodulatory properties on Natural Killer (NK) cells, Dendritic Cells (DC), and T cells. This study compared the use of MSC isolated from bone marrow and fetal liver (FL-MSC) to determine which displayed the most efficient immunosuppressive effects on T cell activation. Although both types of MSC exhibit similar phenotype profile, FL-MSC displays a much more extended in vitro life-span and immunomodulatory properties. When co-cultured with CD3/CD28-stimulated T cells, both BM-MSC and FL-MSC affected T cell proliferation by inhibiting their entry into the cell cycle, by inducing the down-regulation of phospho-retinoblastoma (pRb), cyclins A and D1, as well as up-regulating p27kip1expression. The T cell inhibition by MSC was not due to the soluble HLA-G5 isoform, but to the surface expression of HLA-G1, as shown by the need of cell-cell contact and by the use of neutralizing anti-HLA-G antibodies. To note, in a HLA-G-mediated fashion, MSC facilitated the expansion of a CD4low/CD8low T subset that had decreased secretion of IFN-γ, and an induced secretion of the immunomodulatory cytokine IL-10. Because of their longer lasting in vitro immunosuppressive properties, mainly mediated by HLA-G, and their more efficient induction of IL-10 production and T cell apoptosis, fetal liver MSC could be considered a new tool for MSC therapy to prevent allograft rejection
Linkage mapping of the Phg-1 and Co-14 genes for resistance to angular leaf spot and anthracnose in the common bean cultivar AND 277
The Andean common bean AND 277 has the Co-14 and the Phg-1 alleles that confer resistance to 21 and eight races, respectively, of the anthracnose (ANT) and angular leaf spot (ALS) pathogens. Because of its broad resistance spectrum, Co-14 is one of the main genes used in ANT resistance breeding. Additionally, Phg-1 is used for resistance to ALS. In this study, we elucidate the inheritance of the resistance of AND 277 to both pathogens using F2 populations from the AND 277 × Rudá and AND 277 × Ouro Negro crosses and F2:3 families from the AND 277 × Ouro Negro cross. Rudá and Ouro Negro are susceptible to all of the above races of both pathogens. Co-segregation analysis revealed that a single dominant gene in AND 277 confers resistance to races 65, 73, and 2047 of the ANT and to race 63-23 of the ALS pathogens. Co-14 and Phg-1 are tightly linked (0.0 cM) on linkage group Pv01. Through synteny mapping between common bean and soybean we also identified two new molecular markers, CV542014450 and TGA1.1570, tagging the Co-14 and Phg-1 loci. These markers are linked at 0.7 and 1.3 cM, respectively, from the Co-14/Phg-1 locus in coupling phase. The analysis of allele segregation in the BAT 93/Jalo EEP558 and California Dark Red Kidney/Yolano recombinant populations revealed that CV542014450 and TGA1.1570 segregated in the expected 1:1 ratio. Due to the physical linkage in cis configuration, Co-14 and Phg-1 are inherited together and can be monitored indirectly with the CV542014450 and TGA1.1570 markers. These results illustrate the rapid discovery of new markers through synteny mapping. These markers will reduce the time and costs associated with the pyramiding of these two disease resistance genes
Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand
[EN] Currently in the USA, one name is added to the organ transplant waiting list every 15 min. As this list grows rapidly, fewer than one-third of waiting patients can receive matched organs from donors. Unfortunately, many patients who require a transplant have to wait for long periods of time, and many of them die before receiving the desired organ. In the USA alone, over 100,000 patients are waiting for a kidney transplant. However, it is a problem that affects around 6% of the word population. Therefore, seeking alternative solutions to this problem is an urgent work. Here, we review the current promising regenerative technologies for kidney function replacement. Despite many approaches being applied in the different ways outlined in this work, obtaining an organ capable of performing complex functions such as osmoregulation, excretion or hormone synthesis is still a long-term goal. However, in the future, the efforts in these areas may eliminate the long waiting list for kidney transplants, providing a definitive solution for patients with end-stage renal disease.This study was supported by a grant from ALCER-TURIA, ASTELLAS and PRECIPITA CROWDFUNDING.Garcia-Dominguez, X.; Vicente Antón, JS.; Vera Donoso, CD.; Marco-Jiménez, F. (2017). Current Bioengineering and Regenerative Strategies for the Generation of Kidney Grafts on Demand. Current Urology Reports. 18(1):1-8. https://doi.org/10.1007/s11934-017-0650-6S18181Ott HC, Mathisen DJ. Bioartificial tissues and organs: are we ready to translate? Lancet. 2011;378:1977–8.Salvatori M, Peloso A, Katari R, Orlando G. Regeneration and bioengineering of the kidney: current status and future challenges. Curr Urol Rep. 2014;15:379.D’Agati VD. Growing new kidneys from embryonic cell suspensions: fantasy or reality? J Am Soc Nephrol. 2002;11:1763–6.Abouna GM. Organ shortage crisis: problems and possible solutions. Transplant Proc. 2008;40:34–8.Ozbolat IT, Yu Y. Bioprinting toward organ fabrication: challenges and future trends. IEEE Trans Biomed Eng. 2013;60:691–9.Badylak SF, Taylor D, Uygun K. Whole-organ tissue engineering: decellularization and recellularization of three-dimensional matrix scaffolds. Annu Rev Biomed Eng. 2011;13:27–53.Meeus F, Kourilsky O, Guerin AP, Gaudry C, Marchais SJ, London GM. Pathophysiology of cardiovascular disease in hemodialysis patients. Kidney Int Suppl. 2000;76:140–7.Jofré R. Factores que afectan a la calidad de vida en pacientes en prediálisis, diálisis y trasplante renal. Nefrologia. 1999;19:84–90.Villa G, Rodríguez-Carmona A, Fernández-Ortiz L, Cuervo J, Rebollo P, Otero A, et al. Cost analysis of the Spanish renal replacement therapy programme. Nephrol Dial Transplant. 2011;26:3709–14.MJ C, Marshall D, Dilworth M, Bottomley M, Ashton N, Brenchley P. Immunosuppression is essential for successful allogeneic transplantation of the metanephroi. Transplantation. 2009;88:151–9.Xinaris C, Yokoo T. Reforming the kidney starting from a single-cell suspension. Nephron Exp Nephrol. 2014;126:107.Nguyen DM, El-Serag HB. The epidemiology of obesity. Gastroenterol Clin N Am. 2010;39:1–7.Song JJ, Guyette JP, Gilpin SE, Gonzalez G, Vacanti JP, Ott HC. Regeneration and experimental orthotopic transplantation of a bioengineered kidney. Nat Med. 2013;19:646–51.Hariharan K, Kurtz A, Schmidt-Ott KM. Assembling kidney tissues from cells: the long road from organoids to organs. Front Cell Dev Biol. 2015;3:70.Montserrat N, Garreta E, Izpisua Belmonte JC. Regenerative strategies for kidney engineering, FEBS J. 2016; in press. doi: 10.1111/febs.13704 .Hammerman MR. Transplantation of renal primordia: renal organogenesis. Pediatr Nephrol. 2007;22:1991–8.Basma H, Soto-Gutiérrez A, Yannam GR, Liu L, Ito R, Yamamoto T, et al. Differentiation and transplantation of human embryonic stem cell-derived hepatocytes. Gastroenterology. 2009;136:990–9.Chambers SM, Fasano CA, Papapetrou EP, Tomishima M, Sadelain M, Studer L. Highly efficient neural conversion of human ES and iPS cells by dual inhibition of SMAD signaling. Nat Biotechnol. 2009;27:275–80.Takahashi T, Lord B, Schulze PC, Fryer RM, Sarang SS, Gullans SR, et al. Ascorbic acid enhances differentiation of embryonic stem cells into cardiac myocytes. Circulation. 2003;107:1912–6.Zhang D, Jiang W, Liu M, Sui X, Yin X, Chen S, et al. Highly efficient differentiation of human ES cells and iPS cells into mature pancreatic insulin-producing cells. Cell Res. 2009;19:429–38.Ledran MH, Krassowska A, Armstrong L, Dimmick I, Renström J, Lang R, et al. Efficient hematopoietic differentiation of human embryonic stem cells on stromal cells derived from hematopoietic niches. Cell Stem Cell. 2008;3:85–98.Yamanaka S, Yokoo T. Current bioengineering methods for whole kidney regeneration. Stem Cells Int. 2015;2015:724047.Xia Y, Nivet E, Sancho-Martinez I, Gallegos T, Suzuki K, Okamura D, et al. Directed differentiation of human pluripotent cells to ureteric bud kidney progenitor-like cells. Nat Cell Biol. 2013;15:1507–15.Taguchi A, Kaku Y, Ohmori T, Sharmin S, Ogawa M, Sasaki H, et al. Redefining the in vivo origin of metanephric nephron progenitors enables generation of complex kidney structures from pluripotent stem cells. Cell Stem Cell. 2014;14:53–67.Simerman AA, Dumesic DA, Chazenbalk GD. Pluripotent muse cells derived from human adipose tissue: a new perspective on regenerative medicine and cell therapy. Clin Transl Med. 2014;3:12.Verdi J, Tan A, Shoae-Hassani A, Seifalian AM. Endometrial stem cells in regenerative medicine. J Biol Eng. 2014;8:20.Maeshima A, Yamashita S, Nojima Y. Identification of renal progenitor-like tubular cells that participate in the regeneration processes of the kidney. J Am Soc Nephrol. 2003;14:3138–46.Sagrinati C, Netti GS, Mazzinghi B, Lazzeri E, Liotta F, Frosali F, et al. Isolation and characterization of multipotent progenitor cells from the Bowman’s capsule of adult human kidneys. J Am Soc Nephrol. 2006;17:2443–56.Oliver JA, Maarouf O, Cheema FH, Martens TP, Al-Awqati Q. The renal papilla is a niche for adult kidney stem cells. J Clin Invest. 2004;114:795–804.Kitamura S, Yamasaki Y, Kinomura M, Sugaya T, Sugiyama H, Maeshima Y, et al. Establishment and characterization of renal progenitor like cells from S3 segment of nephron in rat adult kidney. FASEB J. 2005;19:1789–97.Kitamura S, Sakurai H, Makino H. Single adult kidney stem/progenitor cells reconstitute three-dimensional nephron structures in vitro. Stem Cells. 2015;33:774–84.Li M, Suzuki K, Kim NY, Liu GH, Izpisua Belmonte JC. A cut above the rest: targeted genome editing technologies in human pluripotent stem cells. J Biol Chem. 2014;289:4594–9.Freedman BS, Brooks CR, Lam AQ, Fu H, Morizane R, Agrawal V, et al. Modelling kidney disease with CRISPR-mutant kidney organoids derived from human pluripotent epiblast spheroids. Nat Commun. 2015;6:8715.Hu J, Lei Y, Wong WK, Liu S, Lee KC, He X, et al. Direct activation of human and mouse Oct4 genes using engineered TALE and Cas9 transcription factors. Nucleic Acids Res. 2014;42:4375–90.Den Hartogh SC, Schreurs C, Monshouwer-Kloots JJ, Davis RP, Elliott DA, Mummery CL, et al. Dual reporter MESP1 mCherry/w-NKX2-5 eGFP/w hESCs enable studying early human cardiac differentiation. Stem Cells. 2015;33:56–67.Fukui A, Yokoo T. Kidney regeneration using developing xenoembryo. Curr Opin Organ Transplant. 2015;20:160–4.Chen J, Lansford R, Stewart V, Young F, Alt FW. RAG-2-deficient blastocyst complementation: an assay of gene function in lymphocyte development. Proc Natl Acad Sci U S A. 1993;90:4528–32.Ueno H, Turnbull BB, Weissman IL. Two-step oligoclonal development of male germ cells. Proc Natl Acad Sci U S A. 2009;106:175–80.Fraidenraich D, Stillwell E, Romero E, Wilkes D, Manova K, Basson CT, et al. Rescue of cardiac defects in id knockout embryos by injection of embryonic stem cells. Science. 2004;306:247–52.Kobayashi T, Yamaguchi T, Hamanaka S, Kato-Itoh M, Yamazaki Y, Ibata M, et al. Generation of rat pancreas in mouse by interspecific blastocyst injection of pluripotent stem cells. Cell. 2010;142:787–99.Matsunari H, Nagashima H, Watanabe M, Umeyama K, Nakano K, Nagaya M, et al. Blastocyst complementation generates exogenic pancreas in vivo in apancreatic cloned pigs. Proc Natl Acad Sci U S A. 2013;110:4557–62.Espejel S, Roll GR, McLaughlin KJ, Lee AY, Zhang JY, Laird DJ, et al. Induced pluripotent stem cell-derived hepatocytes have the functional and proliferative capabilities needed for liver regeneration in mice. J Clin Invest. 2010;120:3120–6.Usui J, Kobayashi T, Yamaguchi T, Knisely AS, Nishinakamura R, Nakauchi H. Generation of kidney from pluripotent stem cells via blastocyst complementation. Am J Pathol. 2012;180:2417–26.Aggarwal S, Moggio A, Bussolati B. Concise review: stem/progenitor cells for renal tissue repair: current knowledge and perspectives. Stem Cells Transl Med. 2013;2:1011–9.Yokote S, Yokoo T. Organogenesis for kidney regeneration. Curr Opin Organ Transplant. 2013;18:186–90.Crapo PM, Gilbert TW, Badylak SF. An overview of tissue and whole organ decellularization processes. Biomaterials. 2011;32:3233–43.Berthiaume F, Maguire TJ, Yarmush ML. Tissue engineering and regenerative medicine: history, progress, and challenges. Annu Rev Chem Biomol Eng. 2011;2:403–30.Badylak SF. Xenogeneic extracellular matrix as a scaffold for tissue reconstruction. Transpl Immunol. 2004;12:367–77.Badylak SF. The extracellular matrix as a biologic scaffold material. Biomaterials. 2007;28:3587–93.Ott HC, Matthiesen TS, Goh SK, Black LD, Kren SM, Netoff TI, et al. Perfusion-decellularized matrix: using nature’s platform to engineer a bioartificial heart. Nat Med. 2008;14:213–21.Yokoo T. Kidney regeneration with stem cells: an overview. Nephron Exp Nephrol. 2014;126(2):54.Uygun BE, Soto-Gutierrez A, Yagi H, Izamis ML, Guzzardi MA, Shulman C, et al. Organ reengineering through development of a transplantable recellularized liver graft using decellularized liver matrix. Nat Med. 2010;16:814–20.Ott HC, Clippinger B, Conrad C, Schuetz C, Pomerantseva I, Ikonomou L, et al. Regeneration and orthotopic transplantation of a bioartificial lung. Nat Med. 2010;16:927–33.Montserrat N, Garreta E, Izpisua Belmonte JC. Regenerative strategies for kidney engineering. FEBS J. 2016. doi: 10.1111/febs.13704 .Murphy SV, Atala A. 3D bioprinting of tissues and organs. Nat Biotechnol. 2014;32:773–85.Groll J, Boland T, Blunk T, Burdick JA, Cho DW, Dalton PD, et al. Biofabrication: reappraising the definition of an evolving field. Biofabrication. 2016;8:013001.Mandrycky C, Wang Z, Kim K, Kim DH. 3D bioprinting for engineering complex tissues. Biotechnol Adv. 2016;34:422–34.Uzarski JS, Xia Y, Belmonte JC, Wertheim JA. New strategies in kidney regeneration and tissue engineering. Curr Opin Nephrol Hypertens. 2014;23:399–405.Humes HD, Buffington DA, MacKay SM, Funke AJ, Weitzel WF. Replacement of renal function in uremic animals with a tissue-engineered kidney. Nat Biotechnol. 1999;17:451–5.Chevtchik NV, Fedecostante M, Jansen J, Mihajlovic M, Wilmer M, Rüth M, Masereeuw R, Stamatialis D. Upscaling of a living membrane for bioartificial kidney device. Eur J Pharmacol. 2016.Humes HD, Sobota JT, Ding F, Song JH. A selective cytopheretic inhibitory device to treat the immunological dysregulation of acute and chronic renal failure. Blood Purif. 2010;29:183–90.Tumlin J, Wali R, Williams W, Murray P, Tolwani AJ, Vinnikova AK, et al. Efficacy and safety of renal tubule cell therapy for acute renal failure. J Am Soc Nephrol. 2008;19:1034–40.Yokoo T, Ohashi T, Shen JS, Sakurai K, Miyazaki Y, Utsunomiya Y, et al. Human mesenchymal stem cells in rodent whole-embryo culture are reprogrammed to contribute to kidney tissues. Proc Natl Acad Sci U S A. 2005;102(9):3296–300.Yokoo T, Fukui A, Ohashi T, Miyazaki Y, Utsunomiya Y, Kawamura T, et al. Xenobiotic kidney organogenesis from human mesenchymal stem cells using a growing rodent embryo. J Am Soc Nephrol. 2006;17:1026–34.Cooper DK. A brief history of cross-species organ transplantation. Proc (Bayl Univ Med Cent). 2012;25:49–57.Costa MR, Fischer N, Gulich B, Tönjes RR. Comparison of porcine endogenous retroviruses infectious potential in supernatants of producer cells and in cocultures. Xenotransplantation. 2014;21:162–73.Takeda S, Rogers SA, Hammerman MR. Differential origin for endothelial and mesangial cells after transplantation of pig fetal renal primordia into rats. Transpl Immunol. 2006;15:211–5.Yasutomi Y. Establishment of specific pathogen-free macaque colonies in Tsukuba Primate Research Center of Japan for AIDS research. Vaccine. 2010;28:75–7.Dekel B, Burakova T, Arditti FD, Reich-Zeliger S, Milstein O, Aviel-Ronen S, et al. Human and porcine early kidney precursors as a new source for transplantation. Nat Med. 2003;9:53–60.Hammerman MR. Classic and current opinion in embryonic organ transplantation. Curr Opin Organ Transplant. 2014;19:133–9.Rogers SA, Hammerman MR. Prolongation of life in anephric rats following de novo renal organogenesis. Organogenesis. 2004;1:22–5.•• Yokote S, Matsunari H, Iwai S, Yamanaka S, Uchikura A, Fujimoto E, et al. Urine excretion strategy for stem cell-generated embryonic kidneys. Proc Natl Acad Sci U S A. 2015;112:12980–5. This manuscript describes the developed-metanephros ability to produce urine when it was connected to the excretory system of the recipient organism. They demonstrated the potential of this technique as a possible solution to the kidneys shortage.Yokote S, Yokoo T, Matsumoto K, Utsunomiya Y, Kawamura T, Hosoya T. The effect of metanephroi transplantation on blood pressure in anephric rats with induced acute hypotension. Nephrol Dial Transplant. 2012;27:3449–55.Matsumoto K, Yokoo T, Yokote S, Utsunomiya Y, Ohashi T, Hosoya T. Functional development of a transplanted embryonic kidney: effect of transplantation site. J Nephrol. 2012;25:50–5.Yokote S, Yokoo T, Matsumoto K, Ohkido I, Utsunomiya Y, Kawamura T, et al. Metanephroi transplantation inhibits the progression of vascular calcification in rats with adenine-induced renal failure. Nephron Exp Nephrol. 2012;120:e32–40.Matsumoto K, Yokoo T, Matsunari H, Iwai S, Yokote S, Teratani T, et al. Xeno‐transplanted embryonic kidney provides a niche for endogenous mesenchymal stem cell differentiation into erythropoietin-producing tissue. Stem Cells. 2012;30:1228–35.Abrahamson DR. Glomerular development in intraocular and intrarenal graft of fetal kidney. Lab Investig. 1991;64:629–39.Woolf AS, Palmer SJ, Snow ML, Fine LG. Creation of functioning chimeric mammalian kidney. Kidney Int. 1990;38:991–7.Robert B, St John PL, Hyink DP, Abrahamson DR. Evidence that embryonic kidney cells expressing flk-1 are intrinsic, vasculogenic angioblasts. Am J Physiol. 1996;271:F744–53.Koseki C, Herzlinger D, Al-Awqati Q. Integration of embryonic nephrogenic cells carrying a reporter gene into functioning nephrons. Am J Physiol. 1991;261:C550–4.Rogers SA, Lowell JA, Hammerman NA, Hammerman MR. Transplantation of developing metanephroi into adult rats. Kidney Int. 1998;54:27–37.Barakat TL, Harrison RG. The capacity of fetal and neonatal renal tissues to regenerate and differentiate in a heterotropic allogenic subcutaneous tissue site in the rat. J Anat. 1971;110:393–407.Rogers SA, Liapis H, Hammerman MR. Transplantation of metanephroi across the major histocompatibility complex in rats. Am J Physiol Regul Integr Comp Physiol. 2001;280:R132–6.Vera-Donoso CD, García-Dominguez X, Jiménez-Trigos E, García-Valero L, Vicente JS, Marco-Jiménez F. Laparoscopic transplantation of metanephroi: a first step to kidney xenotransplantation. Actas Urol Esp. 2015;39:527–34.•• Marco-Jiménez F, Garcia-Dominguez X, Jimenez-Trigos E, Vera-Donoso CD, Vicente JS. Vitrification of kidney precursors as a new source for organ transplantation. Cryobiology. 2015;70:278–82. This study found that it is possible to create a long-term biobank of kidney precursors as an unlimited source of organs for transplantation and open new therapeutic possibilities for the patients with chronic renal failure.Garcia-Dominguez X, Vicente JS, Vera-Donoso C, Jimenez-Trigos E, Marco-Jiménez F. First steps towards organ banks: vitrification of renal primordia. CryoLetters. 2016;37:47–52.•• García-Domínguez X, Vera-Donoso CD, García-Valero L, Vicente JS, Marco-Jiménez F. Embryonic organ transplantation: the new era of xenotransplantation. In: Abdeldayem H, El-Kased AF, El-Shaarawy A, editors. Frontiers in transplantology. 2016. pp. 26–46. This manuscript describes for the first time the protocol for transplantation of embryonic kidneys as an organ replacement therapy using laparoscopic surgery.Bottomley MJ, Baicu S, Boggs JM, Marshall DP, Clancy M, Brockbank KG, et al. Preservation of embryonic kidneys for transplantation. Transplant Proc. 2005;37:280–4.Hara J, Tottori J, Anders M, Dadhwal S, Asuri P, Mobed-Miremadi M. Trehalose effectiveness as a cryoprotectant in 2D and 3D cell cultures of human embryonic kidney cells. Artif Cells Nanomed Biotechnol. 2016. doi: 10.3109/21691401.2016.1167698 .Xu Y, Zhao G, Zhou X, Ding W, Shu Z, Gao D. Biotransport and intracellular ice formation phenomena in freezing human embryonic kidney cells (HEK293T). Cryobiology. 2014;68:294–302
Global Retinoblastoma Presentation and Analysis by National Income Level.
Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs
Measurement of VH, H → b b ¯ production as a function of the vector-boson transverse momentum in 13 TeV pp collisions with the ATLAS detector
Cross-sections of associated production of a Higgs boson decaying into bottom-quark pairs and an electroweak gauge boson, W or Z, decaying into leptons are measured as a function of the gauge boson transverse momentum. The measurements are performed in kinematic fiducial volumes defined in the `simplified template cross-section' framework. The results are obtained using 79.8 fb-1 of proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider at a centre-of-mass energy of 13 TeV. All measurements are found to be in agreement with the Standard Model predictions, and limits are set on the parameters of an effective Lagrangian sensitive to modifications of the Higgs boson couplings to the electroweak gauge bosons
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
Comparative study of curcumin and curcumin formulated in a solid dispersion: Evaluation of their antigenotoxic effects
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