Impact of timing of adjuvant chemotherapy initiation and completion after surgery on racial disparities in survival among women with breast cancer.

While large differences by race/ethnicity in breast cancer survival are well established, it is unknown whether differences in quality of chemotherapy delivered explain the racial/ethnic disparities in survival among black, Hispanic, Asian, and white women with breast cancer. We evaluated factors associated with time to initiation of adjuvant chemotherapy and chemotherapy completion and examined outcomes data among women with breast cancer. Patients who initiated chemotherapy later than 3 months after surgery were 1.8 times more likely to die of breast cancer (95 % CI 1.3-2.5) compared with those who initiated chemotherapy less than a month after surgery, even after controlling for known confounders or controlling for race/ethnicity. Women who completed chemotherapy had significantly higher survival compared with those who have not completed chemotherapy. Despite correcting for chemotherapy initiation and completion and known predictors of outcome, African American women still had worse disease-specific survival than their Caucasian counterparts. While a complete and timely adjuvant treatment among various ethnic populations would help to reduce racial disparities in survival, there are still other factors to be identified that may explain the remaining differences in survival between ethnic women with breast cancer.

Expression profiling of the Arabidopsis annexin gene family during germination, de-etiolation and abiotic stress.

Annexins are a multigene family in most plant species and are suggested to play a role in a wide variety of essential cellular processes. In Arabidopsis thaliana there are eight different annexins (AnnAt1-8), which range from 29% to 83% in deduced amino acid sequence identity. As a first step toward clarifying the individual functions of these annexins, in this study we have used quantitative real time reverse transcription PCR to assess their differential expression in different tissues or after different stimuli. We determined which annexins are expressed during germination and early seedling growth by assaying annexin expression levels in dry and germinating seeds and in 7-day-old light-grown seedlings. Our results indicate that transcripts for all eight annexins are present in germinating seeds and that transcript levels for all the annexins increase by 7 days of normal growth. We assayed transcript levels in dark grown roots, cotyledons, and hypocotyls and found that the relative abundance of each annexin varied in these dark-grown tissues. We also examined the effects of red and far red light treatments on annexin expression in 5.5-day-old etiolated seedlings. Light treatments significantly altered transcript levels in hypocotyls and cotyledons for only two members of the gene family. Finally, we monitored annexin expression changes in response to a variety of abiotic stresses. We found that the expression of most of the Arabidopsis annexin genes is differentially regulated by exposure to salt, drought, and high- and low-temperature conditions, indicating a likely role for members of this gene family in stress responses.

Diabetes increases the risk of hepatocellular carcinoma in the United States: a population based case control study.

BACKGROUND: Diabetes has been associated with an increased risk of hepatocellular carcinoma (HCC) in studies of referred patients. This is the first population based case control study in the USA to examine this association while adjusting for other major risk factors related to HCC. METHODS: We used the Surveillance Epidemiology and End-Results Program (SEER)-Medicare linked database to identify patients aged 65 years and older diagnosed with HCC and randomly selected non-cancer controls between 1994 and 1999. Only cases and controls with continuous Medicare enrollment for three years prior to the index date were examined. Inpatient and outpatient claims files were searched for diagnostic codes indicative of diabetes, hepatitis C virus (HCV), hepatitis B virus (HBV), alcoholic liver disease, and haemochromatosis. HCC patients without these conditions were categorised as idiopathic. Unadjusted and adjusted odds ratios were calculated in logistic regression analyses. RESULTS: We identified 2061 HCC patients and 6183 non-cancer controls. Compared with non-cancer controls, patients with HCC were male (66% v 36%) and non-White (34% v 18%). The proportion of HCC patients with diabetes (43%) was significantly greater than non-cancer controls (19%). In multiple logistic regression analyses that adjusted for demographics features and other HCC risk factors (HCV, HBV, alcoholic liver disease, and haemochromatosis), diabetes was associated with a threefold increase in the risk of HCC. In a subset of patients without these major risk factors, the adjusted odds ratio for diabetes declined but remained significant (adjusted odds ratio 2.87 (95% confidence interval 2.49-3.30)). A significant positive interaction between HCV and diabetes was detected (p<0.0001). Similar findings persisted in analyses restricted to diabetes recorded between two and three years prior to HCC diagnosis. CONCLUSIONS: Diabetes is associated with a 2-3-fold increase in the risk of HCC, regardless of the presence of other major HCC risk factors. Findings from this population based study suggest that diabetes is an independent risk factor for HCC.

Evolutionary perspective on annexin calcium-binding domains.

Molecular systematic analysis of the annexin gene superfamily characterized the evolutionary origin, frequency and range of structural variation in calcium interaction domains that are considered intrinsic for membrane targeting and ion channel function. Approximately 36% of annexin repeat domains in an estimated 100 distinct subfamilies contained amino acid changes consistent with the functional loss of type two calcium-binding sites. At least 11% of annexin domains contained a novel K/H/RGD motif conserved in particular subfamilies and manifest in all phyla, apparently via convergent evolution. The first yeast annexin from Yarrowia lipolytica was classified in the ANXC1 subfamily with fungal and mycetozoan representatives. This clade had intact calcium-binding sites but disruption of the normally well-conserved, mid-repeat 4 region implicated in calcium channel regulation. Conversely, a tandem pair of novel annexins from the amphioxus Branchiostoma floridae resembled annexin A13 in gene structure and conserved the charged amino acids associated with the internal hydrophilic pore, but were devoid of external type 2 calcium-binding sites and incorporated K/RGD motifs instead, like annexin A9. The selective erosion of calcium-binding sites in annexin domains and the occurrence of alternate ligands in the same exposed, interhelical loops are pervasive features of the superfamily. This suggests greater complexity than previously appreciated in the mechanisms controlling annexin membrane interaction and calcium channel operation.

Functional analysis of the human annexin A5 gene promoter: a downstream DNA element and an upstream long terminal repeat regulate transcription.

Human annexin A5 is a ubiquitous protein implicated in diverse signal transduction processes associated with cell growth and differentiation, and its gene regulation is an important component of this function. Promoter transcriptional activity was determined for a wide 5' portion of the human annexin A5 gene, from bp -1275 to +79 relative to the most 5' of several discrete transcription start points. Transfection experiments carried out in HeLa cells identified the segment from bp -202 to +79 as the minimal promoter conferring optimal transcriptional activity. Two canonical Sp1 sites in the immediate 5' flanking region of a CpG island were required for significant transcription. Strong repressive activity in the distal promoter region between bp -717 to -1153 was attributed to the presence of an endogenous retroviral long terminal repeat, homologous with long terminal repeat 47B. The downstream sequence from bp position +31 to +79 in untranslated exon 1 was also essential for transcription, as its deletion from any of the plasmid constructs abolished activity in transfection assays. Electrophoretic mobility-shift assays, Southwestern-blot analysis and affinity chromatography were used to identify a protein doublet of relative molecular mass 35 kDa that bound an octanucleotide palindromic sequence in exon 1. The DNA cis-element resembled an E-box, but did not bind higher molecular mass transcription factors, such as upstream stimulatory factor or activator protein 4. The discovery of a downstream element crucial for annexin A5 gene transcription, and its interaction with a potentially novel transcription factor or complex, may provide a clue to understanding the initiation of transcription by TATA-less, multiple start site promoters.

Fosphenytoin: pharmacokinetics and tolerance of intramuscular loading doses.

PURPOSE: Fosphenytoin (FPHT; Cerebyx) is well absorbed when given intramuscularly (IM). All prior pharmacokinetic studies had the first plasma sample obtained 30 min after IM administration. The objectives of this study were to determine the rate and extent of FPHT absorption and to evaluate the tolerability of IM FPHT compared with IM saline. METHODS: This was an open-label, double-blinded study in which patients received 10 mg/kg dose of IM FPHT in one gluteus and IM saline in the other gluteus. Half the patients received saline injection of equal volume to FPHT (up to 19.5 mL); the other half received 2 mL of saline. Neurologic examination, vital signs, PHT blood samples, injection site examination, and subjective pain scores at injection site were obtained before and at timed intervals for 6 h. RESULTS: Total PHT serum concentrations 10 microg/mL were obtained in 5 min in 14.3% of patients and in 26.3% after 10 min. More than half the patients had therapeutic serum concentrations at 30 min; 45.8% of patients reported no pain at either the FPHT or saline injection site. No significant difference in pain was noted between FPHT and saline injection sites at 60 min and thereafter. Early decrease in blood pressure occurred but was not clinically significant. Classic PHT-induced central nervous system (CNS) side effects were evident in one third of patients within 1 h after injection. CONCLUSIONS: (a) IM FPHT is rapidly absorbed (therapeutic levels achieved as early as 5-20 min). (b) IM FPHT is well tolerated by most patients irrespective of injection volume.

Annexin A11 (ANXA11) gene structure as the progenitor of paralogous annexins and source of orthologous cDNA isoforms.

The genomic organization of the annexin A11 gene was determined in mouse and human to assess its congruity with other family members and to examine the species variation in alternative splicing patterns. Mouse annexin A11 genomic clones were characterized by restriction analysis, Southern blotting, and DNA sequencing, and the homologous human gene (HGMW-approved gene symbol ANXA11) was deciphered from high-throughput genomic sequence with coanalysis of expressed sequence tags. Exons 6-15 of the tetrad core repeat region differ from annexins A7 and A13 but are spliced identically to other phylogenetic descendents, making annexin A11 the putative primary progenitor of up to nine paralogous human annexins. The 5' regions consist of untranslated exon 1, followed by an extensive intron 1 comprising almost half the total gene length of >40 kb, and additional GC-rich exons 2-5 encoding the proline- and glycine-rich amino-terminus. Distinct cDNA isoforms in cow and human were determined to be unique to each species and hence of dubious general significance for this gene's function. Multiple transcription start sites were revealed by primer extension analysis of the mouse gene, and transfection constructs containing the prospective promoter generated transcriptional activity comparable to that of the SV40 promoter. Internal repetitive elements and vicinal gene markers were mapped for the complete human annexin A11 gene sequence to characterize the surrounding genomic environment.

Medicare HMO disenrollment and selective use of medical care: osteoarthritis-related joint replacement.

OBJECTIVE: Recent Medicare health maintenance organization (HMO) disenrollees use a high level of medical services. This study examined admissions for total hip arthroplasty (THA) and osteoarthritis-related knee replacements (OKR) among Medicare HMO disenrollees and continuously enrolled fee-for-service (FFS) beneficiaries to determine whether Medicare beneficiaries are returning to the FFS system to receive quality-of-life enhancing elective care. STUDY DESIGN: Retrospective analysis of Medicare inpatient claims for elderly Medicare beneficiaries residing in South Florida between 1990 and 1993. METHODS: Inpatient admission rates for THA, OKR, and for 2 acute conditions--total hip replacements related to fracture of the hip (HRF) and acute myocardial infarction (AMI)--were estimated for Medicare HMO disenrollees over the 3-month period immediately following their disenrollment. These rates were compared with standardized rates for Medicare FFS enrollees. RESULTS: The annualized adjusted rates of both THA and OKR were 3.5 to 4 times higher among Medicare HMO disenrollees than among FFS beneficiaries (P < or = .0001 for both procedures); substantially smaller differences were noted for HRF (P < or = .05), and no difference was present for AMI. HMO disenrollees and FFS enrollees did not differ in their levels of comorbidity at the time of admission. CONCLUSIONS: These data provide indirect evidence that Medicare HMOs in South Florida are rationing THA and OKR and that beneficiaries respond by returning to the FFS system to seek care. This apparent rationing has important implications regarding for the management of serious, but nonemergent, medical conditions within the evolving Medicare system.

Novel human and mouse annexin A10 are linked to the genome duplications during early chordate evolution.

We have identified and characterized a 12th subfamily of vertebrate annexins by systematic analysis of the primary structure, chromosomal mapping, and molecular evolution of unique cDNA and protein sequences from human and mouse. Distinctive features included rare expression, a codon deletion in conserved repeat 3, and an unusual ablation of the type II calcium-binding sites in tetrad core repeats 1, 3, and 4. The paralogy of novel annexin A10 (following revised nomenclature) was confirmed by FISH-mapping human ANXA10 to chromosome 4q33 and genetic linkage mapping mouse Anxa10 to midchromosome 8. Phylogenetic analysis established that the 5' and 3' halves of the annexin A6 octad are more closely related to annexins A5 and A10, respectively, than they are to each other. Molecular date estimates, paralogy linkage maps between human chromosomes 4 and 5, and annexin structural considerations led to the proposal that annexins A5 and A10 may have been the direct progenitors of annexin A6 octad formation via chromosomal duplication during the genome expansion in early chordates.

Do Medicare HMOs and Medicare FFS differ in their use of the Medicare hospice benefit?

This study compares use of the hospice benefit in Medicare fee-for-service (FFS) and Medicare risk-health maintenance organization (HMO) options in South Florida in 1992. A higher percentage of deaths occurred in hospice in the HMO option than in the FFS option. Compared to individuals in the FFS option, HMO-enrolled hospice users had longer lengths of hospice stay, lower 7-day mortality and higher 180-day (6 month) survival. These differences are consistent with the physician's financial incentives associated with the two programs.

Human annexin 31 genetic mapping and origin.

The cDNA encoding novel human annexin 31 was utilized for chromosomal mapping, structural comparison, and phylogenetic analysis to clarify its genetic relationship to other annexins. The ANX31 gene locus was mapped by fluorescence in situ hybridization to human chromosome 1q21, remote from ten other paralogous human annexins on different chromosomes but near the epidermal differentiation gene complex, the S100A gene cluster and a breast-cancer translocation region. Protein homology testing and characterization of incompletely processed expressed sequence tags identified annexin 2 as the closest extant homologue. Maximum likelihood analysis confirmed its most recent common ancestor with vertebrate annexin 2 and validated its classification, in order of discovery, as annexin 31. This subfamily was formed approx. 500-600millionyears ago, subsequent to the gene duplication that produced annexin 1. It has diverged relatively rapidly and extensively, and specifically in the well-conserved, functionally critical type II calcium-binding sites.

Mouse annexin V genomic organization includes an endogenous retrovirus.

Mouse annexin V genomic clones were characterized by restriction analysis, Southern blotting and DNA sequencing. The entire gene spans close to 50 kb of the mouse genome and contains 14 exons ranging in size from 31 bp for exon 2 to 482 bp for exon 13 up to the polyadenylation site. Intron sizes range from 111 bp for intron 1b to more than 17 kb for intron 2. Non-coding exon 1 is present in two alternative forms separated by approx. 7.4 kb, and the two promoters associated with exons 1a and 1b are quite distinct. The upstream promoter has a TATA box and may direct the limited, tissue-specific expression of mRNA transcripts containing exon 1a. The downstream, TATA-less promoter has high G+C content, and exon 1b predominates among abundantly expressed mRNA species. The conservation of certain cis-elements, including Sp1, AP2, gamma-IRE and NF-IL6, in orthologous species of annexin V genes points to their possible role in trans-acting protein factor binding and gene regulation. Primer-extension analysis revealed multiple origins for transcription, with principal start sites 100-150 bp upstream of the ATG start codon in exon 2. Intron 4 was longer than that previously identified in the orthologous rat gene due to the integration of an apparently complete copy of the murine endogenous retrovirus element, MuERV-L. Phylogenetic analysis of annexin V from 12 species and the presence of neighbouring loci with paralogous counterparts linked to annexin VI pointed to the common ancestry of these genes via chromosomal duplication more than 600 million years ago.

Racial and income differences in use of the hospice benefit between the medicare managed care and medicare fee-for-service.

OBJECTIVE: To examine whether use of the Medicare Hospice Benefit between health maintenance organization (HMO) and Fee-For-Service (FFS)-enrolled beneficiaries varies by income or race. DATA SOURCE: Medicare enrollment and claims data for South Florida. RESULTS: In the FFS system, rate of death in hospice varied by income. In the HMO system, it did not. Time spent in hospice varied by income in the HMO system and not in the FFS system. There was little evidence that racial differences in hospice use differed between FFS and HMO options. CONCLUSIONS: These differences raise questions about whether some hospice use may be in response to system-level incentives.

Expression profile and structural divergence of novel human annexin 31.

Systematic analysis of expressed sequence tags in dbEST yielded an expression profile of the ten known human annexins and led to the discovery of a novel subfamily expressed mainly in differentiating tissues. Full-length cDNAs encoded a 338-amino acid protein with less than 40% identity to other annexins, an atypical amino acid composition, and an insertion and deletion in internal repeat 3. The most striking feature was a complete ablation of all four type II calcium-binding sites in the conserved tetrad core. Annexin 31 thus constitutes a unique, natural probe for investigating the role of membrane binding in annexin function.

Mouse annexin III cDNA, genetic mapping and evolution.

Mouse annexin III cDNA was characterized from I.M.A.G.E. Consortium (LLNL) expressed sequence tag clones by molecular sequencing, chromosomal mapping and systematic analysis. cDNA sequences extended the known 5' and 3' untranslated regions and confirmed the location of intron 7 with respect to the human gene. The Anx3 locus mapped to the middle of mouse chromosome 5 between Areg and Fgf5. Protein-coding regions were compared with homologous annexins to establish subfamily identity, structural conservation and divergence pattern. Annexin III exhibited low functional constraint against structural change and weak phylogenetic association with known annexins. The rapid, constant divergence of human and rodent annexins III from each other and from other annexin subfamilies was used to estimate gene separation times. Phylogenetic, phenetic and structural data suggested a possible direct or indirect separation of annexin III from XI approximately 317 million years ago.

Genomic locations of ANX11 and ANX13 and the evolutionary genetics of human annexins.

We have reconstructed a molecular genetic history of human annexins to chronicle their origins and dispersal throughout the genome. This involved the completion of chromosomal mapping, determination of ancestral relationships, and estimation of gene duplication dates. Fluorescence in situ hybridization localized human annexin XI (ANX11) to 10q22.3-q23.1 and annexin XIII (ANX13) to 8q24.1-q24.2. Orthologous annexins showed minor rate variation when calibrated to species separation times given by the fossil record, but paralogous subfamilies have diverged at fivefold variable rates. The rates and extents of sequence divergence were used to predict a mean separation time of 450 million years between vertebrate annexins, although their common ancestor may have emanated from invertebrate stock. Annexins XIII and VII formed a phylogenetically early clade, and annexins II and VIa were the most divergent members of two distinct clades. ANX6 may have been created by tandem duplication about 500 million years ago (Mya) and duplicated again to form ANX5 400 Mya, whereas ANX4 and ANX8 are proposed to be sequential duplication products from annexin XI. Vertebrate annexins thus proliferated via a cascade of gene duplications in higher metazoa to form at least three diverging groups of ubiquitous and structurally related genes. These can be distinguished by their dispersed genomic locations as well as their individual patterns of expression and partially differentiated functions.

Medicare HMOs: who joins and who leaves?

Medicare risk health maintenance organizations (HMOs) are an increasingly common alternative to fee-for-service Medicare. To date, there has been no examination of whether the HMO program is preferentially used by blacks or by persons living in lower-income areas or whether race and income are associated with reversing Medicare HMO selection. This question is important because evidence suggests that these beneficiaries receive poorer care under the fee-for-service-system than do whites and persons from wealthier areas. Medicare enrollment data from South Florida were examined for 1990 to 1993. Four overlapping groups of enrollees were examined: all age-eligible (age 65 and over) beneficiaries in 1990; all age-eligible beneficiaries in 1993; all age-eligible beneficiaries residing in South Florida during the period 1990 to 1993; and all beneficiaries who became age-eligible for Medicare benefits between 1990 and 1993. The associations between race or income and choice of Medicare option were examined by logistic regression. The association between the demographic characteristics and time staying with a particular option was examined with Kaplan-Meier methods and Cox Proportional Hazards modeling. Enrollment in Medicare risk HMOs steadily increased over the 4-year study period. In the overall Medicare population, the following statistically significant patterns of enrollment in Medicare HMOs were seen: enrollment of blacks was two times higher than that of non-blacks; enrollment decreased with age; and enrollment decreased as income level increased. For the newly eligible population, initial selection of Medicare option was strongly linked to income; race effects were weak but statistically significant. The data for disenrollment from an HMO revealed a similar demographic pattern. At 6 months, higher percentages of blacks, older beneficiaries (older than 85), and individuals from the lowest income area (less than $15,000 per year) had disenrolled. A small percentage of beneficiaries moved between HMOs and FFS plans multiple times. These data on Medicare HMO populations in South Florida, an area with a high concentration of elderly individuals and with one of the highest HMO enrollment rates in the country, indicate that enrollment into and disenrollment from Medicare risk HMOs are associated with certain demographic characteristics, specifically, black race or residence in a low-income area.

The genetic origin of mouse annexin VIII.

Mouse annexin VIII cDNA was characterized by DNA sequencing of expressed sequence tag clones, molecular systematic analysis, and genetic linkage mapping to investigate its evolutionary origin. Its subfamily identity, divergence pattern, and nucleotide substitution rate were established by comparison with other annexin cDNA and deduced protein sequences. The known phylogenetic association of annexin VIII in an evolutionary clade with annexins XI, IV, V, and VIa identified these close homologs as potential progenitors or duplication products. Cladistic analysis confirmed the base position of annexin XI and its relationship to annexin IV as a direct duplication product. Although annexin VIII also derived from annexin XI, the evolutionary branching order, gene separation times, and mapping results indicated that it was probably a subsequent duplication product of annexin IV about 300 million years ago. Dates were calibrated against the assumed separation time of 75 Mya for rodents from other mammals, divergence rates were based on comparisons of all available annexin species, and relative rate tests implied individually stable gene clocks for most annexins. Linkage mapping of mouse Anx8 to the centromeric region of Chromosome (Chr) 14 placed it in a more distal homology group from previously mapped Anx7 and Anx11. Despite their synteny, the combined proximity and segregation of these three annexins diminished the likelihood that they were mutual gene duplication products.

The Medicare-HMO revolving door--the healthy go in and the sick go out.

BACKGROUND: Enrollment in Medicare health maintenance organizations (HMOs) is encouraged because of the expectation that HMOs can help slow the growth of Medicare costs. However, Medicare HMOs, which are paid 95 percent of average yearly fee-for-service Medicare expenditures, are increasingly believed to benefit from the selective enrollment of healthier Medicare recipients. Furthermore, whether sicker patients are more likely to disenroll from Medicare HMOs, thus raising average fee-for-service costs, is not clear. METHODS: We used Medicare enrollment and inpatient billing records for southern Florida from 1990 through 1993 to examine differences in the use of inpatient medical services by 375,406 beneficiaries in the Medicare fee-for-service system, 48,380 HMO enrollees before enrollment, and 23,870 HMO enrollees after disenrollment. We also determined whether these differences were related to demographic characteristics and whether the pattern of use after disenrollment persisted over time. RESULTS: The rate of use of inpatient services in the HMO-enrollment group during the year before enrollment was 66 percent of the rate in the fee-for-service group, whereas the rate in the HMO-disenrollment group after disenrollment was 180 percent of that in the fee-for-service group. Beneficiaries who disenrolled from HMOs re-enrolled at about the time that their level of use dropped to that in the fee-for-service group. CONCLUSIONS: These data show marked selection biases with respect to HMO enrollment and disenrollment. These biases undermine the effectiveness of the Medicare managed-care system and highlight the need for longitudinal and population-based studies.