43 research outputs found

    X Linkage of AP3A, a Homolog of the Y-Linked MADS-Box Gene AP3Y in Silene latifolia and S. dioica

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    Background: The duplication of autosomal genes onto the Y chromosome may be an important element in the evolution of sexual dimorphism.A previous cytological study reported on a putative example of such a duplication event in a dioecious tribe of Silene (Caryophyllaceae): it was inferred that the Y-linked MADS-box gene AP3Y originated from a duplication of the reportedly autosomal orthologAP3A. However, a recent study, also using cytological methods, indicated that AP3A is X-linked in Silenelatifolia. Methodology/Principal Findings: In this study, we hybridized S. latifolia and S. dioicato investigate whether the pattern of X linkage is consistent among distinct populations, occurs in both species, and is robust to genetic methods. We found inheritance patterns indicative of X linkage of AP3A in widely distributed populations of both species. Conclusions/Significance: X linkage ofAP3A and Y linkage of AP3Yin both species indicates that the genes ’ ancestral progenitor resided on the autosomes that gave rise to the sex chromosomesand that neither gene has moved between chromosomes since species divergence.Consequently, our results do not support the contention that inter-chromosomal gene transfer occurred in the evolution of SlAP3Y from SlAP3A

    The identification of the B S breakpoint and of two possible Bar genes

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    Two coding regions were identified within a 110 kb region which includes all mapped Bar breakpoints. Both lie proximal to the identified Bar breakpoints. The first coding region, designated BarA , is 5 kb from the most proximal Bar mutation, B 581 , and 66 kb from the B S breakpoint. It encodes a 1.3 kb transcript, which is found in late third instar larvae but is absent in 1–3-day-old pupae. B i , R(B) hd3 , B 85c1s and B S result in overproduction of this transcript in late third instar larvae. A second coding region, which was previously identified as BarH1 , maps 18 kb from B 581 and 79 kb from the B S breakpoint. In third instar larvae, the abundance of the BarH1 transcript is very low in both wild type and various Bar mutatants, with the exception of R(B) hd3 . In 1–3-day-old pupae, the level of the BarH1 transcript is higher. BarH1 was previously identified as the Bar gene. However, this report raises the possibility that BarA rather than BarH1 is the Bar gene or that more than one gene may be involved in Bar position effects.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47582/1/438_2004_Article_BF00587567.pd

    Toward estimating the impact of changes in immigrants' insurance eligibility on hospital expenditures for uncompensated care

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    BACKGROUND: The Personal Responsibility and Work Opportunity Reconciliation Act (PRWORA) of 1996 gave states the option to withdraw Medicaid coverage of nonemergency care from most legal immigrants. Our goal was to assess the effect of PRWORA on hospital uncompensated care in the United States. METHODS: We collected the following state-level data for the period from 1994 through 1999: foreign-born, noncitizen population and health uninsurance rates (US Census Current Population Survey); percentage of teaching hospitals (American Hospital Association Annual Survey of Hospitals); and each state's decision whether to implement the PRWORA Medicaid bar for legal permanent residents or to continue offering nonemergency Medicaid coverage using state-only funds (Urban Institute). We modeled uncompensated care expenditures by state (also from the Annual Survey of Hospitals) in both univariate and multivariable regression analyses. RESULTS: When measured at the state level, there was no significant relationship between uncompensated care expenditures and states' percentage of noncitizen immigrants. Uninsurance rates were the only significant factor in predicting uncompensated hospital care expenditures by state. CONCLUSIONS: Reducing the number of uninsured patients would most surely reduce hospital expenditures for uncompensated care. However, data limitations hampered our efforts to obtain a monetary estimate of hospitals' financial losses due specifically to the immigrant eligibility changes in PRWORA. Quantifying the impact of these provisions on hospitals will require better data sources
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