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Adjusting for reporting delay in cancer incidence when combining different sets of cancer registries
Douglas Midthune Martin Krapcho Zhaohui Zou Marie‐Joseph Horner Eric J. Feuer 《Biometrical journal. Biometrische Zeitschrift》2013,55(5):755-770
Cancer registries collect cancer incidence data that can be used to calculate incidence rates in a population and track changes over time. For incidence rates to be accurate, it is critical that diagnosed cases be reported in a timely manner. Registries typically allow a fixed amount of time (e.g. two years) for diagnosed cases to be reported before releasing the initial case counts for a particular diagnosis year. Inevitably, however, additional cases are reported after the initial counts are released; these extra cases are included in subsequent releases that become more complete over time, while incidence rates based on earlier releases will underestimate the true rates. Statistical methods have been developed to estimate the distribution of reporting delay (the amount of time until a diagnosed case is reported) and to correct incidence rates for underestimation due to reporting delay. Since the observed reporting delays must be less than the length of time the registry has been collecting data, most methods estimate a truncated delay distribution. These methods can be applied to a group of registries that began collecting data in the same diagnosis year. In this paper, we extend the methods to two groups of registries that began collecting data in two different diagnosis years (so that the delay distributions are truncated at different times). We apply the proposed method to data from the National Cancer Institute's Surveillance Epidemiology and End Results (SEER) program, a consortium of U.S. cancer registries that includes nine registries with data collection beginning in 1981 and four registries with data collection beginning in 1992. We use the method to obtain delay‐adjusted incidence rates for melanoma, liver cancer, and Hodgkin lymphoma. 相似文献
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Lászlo Bátkai Mihály Nográdi Loránd Farkas Lászlo Feuer István Horváth 《Archives of microbiology》1973,90(2):165-166
Summary The ability of various strains of fungi to transform isoflavones was studied. It was found that demethylation of 7-methoxyisoflavon is effected by Penicillium cyclopium. 相似文献
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Ralph Feuer Chelsea M. Ruller Naili An Jenna M. Tabor-Godwin Ross E. Rhoades Sonia Maciejewski Robb R. Pagarigan Christopher T. Cornell Stephen J. Crocker William B. Kiosses Ngan Pham-Mitchell Iain L. Campbell J. Lindsay Whitton 《Journal of virology》2009,83(18):9356-9369
Coxsackieviruses are significant human pathogens, and the neonatal central nervous system (CNS) is a major target for infection. Despite the extreme susceptibility of newborn infants to coxsackievirus infection and viral tropism for the CNS, few studies have been aimed at determining the long-term consequences of infection on the developing CNS. We previously described a neonatal mouse model of coxsackievirus B3 (CVB3) infection and determined that proliferating stem cells in the CNS were preferentially targeted. Here, we describe later stages of infection, the ensuing inflammatory response, and subsequent lesions which remain in the adult CNS of surviving animals. High levels of type I interferons and chemokines (in particular MCP-5, IP10, and RANTES) were upregulated following infection and remained at high levels up to day 10 postinfection (p.i). Chronic inflammation and lesions were observed in the hippocampus and cortex of surviving mice for up to 9 months p.i. CVB3 RNA was detected in the CNS up to 3 months p.i at high abundance (∼106 genomes/mouse brain), and viral genomic material remained detectable in culture after two rounds of in vitro passage. These data suggest that CVB3 may persist in the CNS as a low-level, noncytolytic infection, causing ongoing inflammatory lesions. Thus, the effects of a relatively common infection during the neonatal period may be long lasting, and the prognosis for newborn infants recovering from acute infection should be reexplored.Early damaging events on the central nervous system (CNS) by infection can result not only in severe physical and intellectual disability but also in less obvious neurological deficits. For example, children who were thought to have fully recovered from neonatal CNS virus infections exhibited some deficiency in scholastic performance (12). Thus, the enduring harmful effects of childhood infections on the CNS may be greatly underappreciated. Picornaviruses including polioviruses, coxsackieviruses, and other unclassified enteroviruses frequently infect the CNS (60). Although these infections often are considered acute and self-limiting, evidence is emerging that these viruses—or at least the viral RNAs—may persist for months or years after the initial infection. For example, ∼50 years after the primary infection, a large percentage (∼30%) of polio victims are now experiencing new symptoms (postpolio syndrome), which some investigators have correlated with the presence of viral RNA in the CNS (43). Worldwide distribution of enterovirus infection is revealed by the detection of enterovirus-specific antibodies in the serum of approximately 75% of individuals within developed countries. For example, in 1996, approximately 10 to 15 million diagnosed cases of enterovirus infection occurred in the United States alone (49). Few studies have been done to determine if enteroviruses, or their close relatives, have the ability to persist and cause long-term damage in the CNS (10, 56) or whether previous infection of neurons may indirectly lead to the degeneration of aging motor neurons.Coxsackievirus, a member of the enterovirus genus, is a fairly frequent childhood infection and may cause severe morbidity and mortality in humans, predominantly in the very young. Infants infected with coxsackievirus have been shown to be extremely susceptible to meningitis and encephalitis. Severe demyelinating diseases may occur following infection, including acute disseminated encephalomyelitis (18) and acute transverse myelitis (27). Also, a number of delayed neuropathologies have been associated with previous coxsackievirus infection, including schizophrenia (47, 52), encephalitis lethargica (16), and amyotrophic lateral sclerosis (62, 63). If human neurotropic viruses persist, they could provide a chronic inflammatory stimulus, leading to regional cytokine induction and activation of autoreactive T cells through molecular mimicry and bystander activation (32, 45). This may be especially true for viruses, such as coxsackievirus, which have the ability to infect stem cells (24) and neurons (1). Recently, we have shown that coxsackievirus B3 (CVB3) targets proliferating cells in regions of the neonatal CNS supporting neurogenesis (24). Nonetheless, infected migratory neuronal progenitor cells were able to differentiate into mature neurons. Many neurons eventually underwent caspase-3-mediated apoptosis at later stages of disease (22).Intriguingly, viral RNA was detected in the CNS of surviving pups in the absence of infectious virus for up to 30 days postinfection (p.i.). The detection of CVB3 RNA in target tissues may have great significance for CVB3-mediated disease, given that the long-term presence of replication-restricted CVB3 RNA in the heart (generated using transgenic techniques) has been directly associated with dilated cardiomyopathy in a previous study by Wessely et al. (59). We were therefore interested in expanding this notable observation in the CNS by significantly increasing the number of animals examined, more precisely quantifying the amounts of viral RNA, and determining how long viral RNA might persist in the CNS. In addition, we thoroughly assessed the nature and degree of neuropathology in surviving animals harboring CVB3 RNA. These studies may help predict the lasting neurological sequelae of a previous viral infection on the developing host. 相似文献
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Abstract. Woodland colonization on wetlands is considered to have a detrimental effect on their ecological value, even though detailed analysis of this process is lacking. This paper provides an evaluation of the ecological changes resulting from succession of poor fen (base‐poor mire) to willow wet woodland on Goss Moor NNR in Cornwall, UK. Different ages of willow carr were associated with eight understorey communities. During willow colonization, in the ground flora, there was a progressive decrease in poor fen species and an associated increase in woodland species, which appeared to be related to an increase in canopy cover and therefore shade. The most diverse community was found to be the most recent willow and was dominated by poor fen species. The oldest willow was the second most diverse and was associated with a reduction in poor fen species and an increase in woodland species. Architectural features were used successfully to assess the general condition and structure of willow. Tree height and DBH were identified as useful parameters to accurately assess willow age in the field. The implications of active intervention to remove willow in order to conserve the full range of communities within the hydrosere are discussed. 相似文献
17.
Sylvia Feuer 《Grana》2013,52(4):225-242
This is the first of two papers detailing pollen morphology and evolution with the tribe Embothrieae comprising eight genera and ca. 56 spp. The present paper examines pollen of subtribes Buckinghaminae (Buckinghamia; 2 spp., Opislhiolepis; 1 sp.), Stenocarpinae (Strangea; 3 spp.), Stenocarpus (ca. 27 spp.) and Lomatiinae (Lomatia; ca. 12 spp.) in the light microscope and scanning and transmission electron microscopes. Pollen is medium-sized, oblate, foveolate to microreticulate to reticulate, and predominantly columellate with a complex modified postvestibulate aperture morphology. Pollen data indicate ties between Lomatia and Stenocarpus on the one hand and Stenocarpus and Strangea on the other. Though Buckinghamia and Opislhiolepis have been placed in the same subtribe, the unique combination of pollen features in each suggests only a remote relationship to each other as well as to remaining Embothrieae. Comparisons to the remaining genera of Embothriae (Embothrium, Oreocallis, Telopea) and overall analysis of pollen evolution within the tribe are detailed in the subsequent paper. 相似文献
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BŁAŻEJ BERKOWSKI CHRISTIAN KLUG 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2012,45(1):24-33
Berkowski, B & Klug, C. 2011: Lucky rugose corals on crinoid stems: unusual examples of subepidermal epizoans from the Devonian of Morocco. Lethaia, Vol. 45, pp. 24–33. In the fossil record, evidence for true epizoans, i.e. living animals inhabiting other living host‐animals, is rather rare. A host reaction is usually needed to proof the syn vivo‐settling of the epizoan. Herein, we provide a first report of such an epizoan biocoenosis from various strata of the Early Devonian of Hamar Laghdad, the world‐renowned Moroccan mud‐mound locality. In this case, solitary rugose corals settled as larvae on crinoid stems, perhaps at a spot where the epidermis was missing for some reason (injury, disease). Both the crinoid and the coral began to grow around each other. By doing so, the affected crinoid columnals formed a swelling, where ultimately only an opening slightly larger than the coral orifice remained. We discuss both macroecological and small‐scale synecological aspects of this biocoenosis. The coral profited from its elevated home because it reached into more rapid currents providing the polyp with more food than at the densely populated seafloor, which was probably covered by a coral‐meadow around the mounds and hydrothermal vents. □Corals, crinoids, Early Devonian, epizoans, Morocco, Rugosa. 相似文献
20.
Sylvia M. Feuer 《American journal of botany》1978,65(7):759-763
The genus Ptychopetulum (Olacaceae), disjunct between South America (2 spp.) and Africa (2 spp. West Africa; I sp. Rhodesia), exhibits predominantly diploporate pollen among the West African species and predominantly triporate pollen among the South American taxa. An analysis of aperture evolution suggests two possible schemes of aperture evolution for the genus. Scheme I avers the independent origin of both triporate and diploporate apertures from a basic brevicolpate condition while scheme II proposes a basic diploporate condition in which the diploporate apertures have migrated to the equator, fused to form brevicolpi and have ultimately become reduced to pores. Pollen evidence in support of both schemes is discussed. The distribution of aperture types within the genus also suggests West Africa as the original site of aperture evolution and South America as the second area of aperture development with types traceable to West African stock. 相似文献