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PubMed1987

Intrapreneurship: growing a successful hospital diversification strategy.

The recent upheaval in the health care industry has left administrators scrambling after strategies that will ensure their organizations' survival. The author discusses Affiliated Healthcare Systems' successful use of a diversification strategy. Special attention is given to explaining how other organizations might use this system's experience to reduce the risks and increase the rewards inherent in this strategic alternative.

Economic Competition↗
PubMed1988

Nursing home diversification requires caution by hospitals.

Hospital executives considering diversifying into long-term care for the elderly need to understand the ways the nursing home acquisition market and the long-term care industry have changed in the past two years and how to best respond to those changes. Diversification into the nursing home business must be carefully planned, taking into account such factors as state Medicaid reimbursement policies; the respective advantages of buying an existing facility or constructing a new one; the need for executives with expertise in long-term care; and the financial requirements of the proposal.

Aged↗
PubMed1987

Diversification strategies for mid-size hospitals.

Selecting the correct diversification strategy is one of the key decisions that today's health administrator wil make, for at no time have more options been available. These strategies must, however, be good uses of the hospital's resources. In this article, the author discusses three strategies appropriate for the mid-size hospital, employee drug testing, workmen's compensation and fitness. Each targets the key employer market segment. The author includes how these can be fitted into the overall program of the hospital.

Decision Making↗
PubMed1999

Recent determinants of new entry of HMOs into a Medicare risk contract: a diversification strategy.

This study provides knowledge of more recent entry of health maintenance organizations (HMOs) into the Medicare risk program than earlier analyses. Based on a diversification framework, this study examines new market entry from three dimensions: attractiveness of the market, market area attributes, and organizational attributes. The analysis uses a 1994-1995 cross-sectional, lagged time sample with 440 HMOs that did not have a Medicare risk contract as of January 1994; it defines an HMO's market as its service area. HMO enrollment growth in the market, individual HMO enrollment size, and adjusted average per capita cost (AAPCC) rates are found to be significant in predicting new market entry.

Contract Services↗
PubMed2001

Structural homology and developmental transformations associated with ovary diversification in Lithophragma (Saxifragaceae).

Lithophragma, comprising only ten species, encompasses a remarkable diversity of ovary positions, reported to range from inferior to superior. The structural homology of the gynoecium and developmental transformations associated with ovary diversification are investigated for Lithophragma. Scanning electron and light microscopy indicate that all species of Lithophragma have epigynous flowers. Lithophragma campanulatum, L. glabrum, and L. heterophyllum have ovaries that externally appear nearly superior, but are actually shallowly inferior or "pseudosuperior." The inferior ovaries of Lithophragma species can be conceptually divided into superior and inferior regions that meet at the point of perianth and androecial insertion. Static and ontogenetic allometry reveal that across the species of Lithophragma the lengths of these two ovary regions are coordinated. Ovary regions in mature flowers display an approximately linear relationship that can be expressed through the allometric equation SL = -0.5314 IL + 2.0348 (where SL and IL are the lengths of the superior and inferior regions of the ovary, respectively; r = 0.7683, df = 35, P = 2.45 × 10). Mapping ontogenetic allometries onto a recent phylogeny for Lithophragma shows that ovary position evolution is bidirectional and has shifted toward greater superiority in some species and greater inferiority in others.

Journal Article↗
PubMed2006

The tempo of avian diversification: a comment on Johnson and Cicero.

Johnson and Cicero (2004) claimed that inspection of a distribution of uncorrected mitochondrial DNA avian sister-taxon distances illustrated that the late Pleistocene was an important time for avian speciation. They believed this finding to be at odds with conclusions of Klicka and Zink (1997). However, both studies document recent speciation events. More germane to the discussion is what is meant by an "important" time for speciation, which we take to mean above some baseline diversification rate. We constructed a null distribution of sister-taxon distances based on a model of constant speciation and extinction rates. The empirical distribution of sister-taxon distances in Johnson and Cicero (2004) did not differ from the null model. Therefore, our analysis of Johnson and Cicero's data suggests that the late Pleistocene was no more important for avian speciation than any other time during this time period.

Animals↗
PubMedDate not supplied

[Principal stages in the Cenozoic diversification of shallow-water molluscan faunas in the North Pacific].

Cluster analysis of bivalve species recorded in Cenozoic deposits in Sakhalin Island, western Kamchatka, Hokkaido, and California was used to determine geological age of the modem North Pacific biogeographic region and its constituent subregions (Japan-Mandchurian, Beringian, and Oregon-Sitkan). The North Pacific region developed during the Paleogene-Neogene transition due to Drake Passage opening to deep-water movement, formation of the deep-water Antarctic Circumpolar Current, and the change in climate from greenhouse to psychospheric. Differentiation of the three subregions within the North Pacific Region seems to have occurred in late Miocene-early Pliocene, about 5.6 millions years ago and was probably due to the flooding of the Bering Land Bridge and development of the present configuration of circulation in the North Pacific. In the Northwest Pacific, during Paleogene and early Neogene, the faunal diversification occurred more rapidly and was more extensive than in the Northeast Pacific.

Animals↗
PubMed1990

Survey: managed care led '89 diversification improvements.

As providers gain increased experience with managed care contracting, they are reporting greater success, especially with preferred provider organizations. And for the second year in a row, the profitability of substance abuse treatment units has declined. These are just a few of the highlights from Hospitals' third annual diversification survey.

Data Collection↗
PubMed1989

[Maximization of economic yield, minimum cost optimal diets and cultivation diversification for small scale farmers of the highland region of Guatemala].

The present study was conducted as part of an evaluation of the economic and nutritional effects of a crop diversification program for small-scale farmers in the Western highlands of Guatemala. Linear programming models are employed in order to obtain optimal combinations of traditional and non-traditional food crops under different ecological conditions that: a) provide minimum cost diets for auto-consumption, and b) maximize net income and market availability of dietary energy. Data used were generated by means of an agroeconomic survey conducted in 1983 among 726 farming households. Food prices were obtained from the Institute of Agrarian Marketing; data on production costs, from the National Bank of Agricultural Development in Guatemala. The gestation periods for each crop were obtained from three different sources, and then averaged. The results indicated that the optimal cropping pattern for the minimum-cost diets for auto consumption include traditional foods (corn, beans, broad bean, wheat, potato), non-traditional foods (carrots, broccoli, beets) and foods of animal origin (milk, eggs). A significant number of farmers included in the sample did not have sufficient land availability to produce all foods included in the minimum-cost diet. Cropping patterns which maximize net incomes include only non-traditional foods: onions, carrots, broccoli and beets for farmers in the low highland areas, and raddish, broccoli, cauliflower and carrots for farmers in the higher parts. Optimal cropping patterns which maximize market availability of dietary energy include traditional and non-traditional foods; for farmers in the lower areas: wheat, corn, beets, carrots and onions; for farmers in the higher areas: potato, wheat, raddish, carrots and cabbage.

Agriculture↗
PubMed1989

Vertical integration strategies: more promising than diversification.

Investment in businesses outside of traditional hospital services can help providers withstand the ill effects of today's business climate. However, the typical diversification approach must be discarded. This article describes a different approach that has been used successfully in other industries--vertical integration.

Commerce↗
PubMed1989

Diversity and diversification of HLA-A,B,C alleles.

The nucleotide sequences encoding 14 HLA-A,B,C and 5 ChLA-A,B,C molecules have been determined. Combining these sequences with published data has enabled the polymorphism in 40 HLA-A,B,C and 9 ChLA-A,B,C alleles to be analyzed. Diversity is generated through assortment of point mutations by recombinational mechanisms including gene and allelic conversions. The distribution and frequency of silent and replacement substitutions indicate that there has been positive selection for allelic diversity in the 5' part of the gene (exons 1 to 3) and for allelic homogenization and locus specificity in the 3' part of the gene (exons 4 to 8). These differences may correlate with the lengths of converted sequences in the two parts of the gene and frequency of the CpG dinucleotide. Locus-specific divergence of HLA-A,B, and C demonstrates that recombinational events involving alleles of a locus have been more important than conversion between loci. This contrasts with the predominance of gene conversion events in the evolution of mutants of the H-2Kb gene. However, a striking example of gene conversion involving HLA-B and C alleles of an oriental haplotype has been found. Comparison of human and chimpanzee alleles reveals extensive sharing of polymorphisms, confirming that diversification is a slow process, and that much of contemporary polymorphism originated in ancestral primate species before the emergence of Homo sapiens. There is less polymorphism at the HLA-A locus compared to HLA-B, with greater similarity also being seen between HLA-A and ChLA-A alleles than between HLA-B and ChLA-B alleles. Although greater diversity is seen in the 5' "variable" exons of HLA-B compared to HLA-A, there is increased heterogeneity in the 3' "conserved" exons of HLA-A compared to HLA-B.

Alleles↗
PubMed1988

Morphological grounds for diversification and evolutionary change in the amphibian sound-conducting apparatus.

The occurrence of 2 alternate sound-conducting elements (operculum - stapes) and paedomorphic trends are responsible for the elaboration of extreme diversity in the structure of the sound-conducting apparatus seen in recent amphibians. It seems possible that the same factors might provide grounds for the large extent of diversification in the middle ear morphology of the early fossil amphibian taxa.

Amphibians↗
PubMed1993

MASH genes and the logic of neural crest cell lineage diversification.

Avian embryos have traditionally been the system of choice for studying neural crest development, but the combination of reverse genetics and clonal culture should allow new insights to be gained from mammalian systems as well. We describe one of the first examples where a targeted mutation in a developmental control gene, isolated on the basis of its homology to Drosophila neural determination genes, causes a highly selective phenotype affecting the early development of a subset of neural crest derivatives. Detailed analysis of the cellular phenotype and expression pattern of the gene, called MASH-1, have led to novel insights into the genetic logic that controls neural crest development. Most important, some features of the phenotype appear inconsistent with the predictions of current models of neural crest lineage diversification. These unexpected results have forced a reevaluation of our thinking about some aspects of neural crest development, and illustrate the power of the reverse genetic approach to reveal unanticipated features of complex biological systems as well as to suggest new directions for future study.

Animals↗
PubMed1993

Molecular diversification of dominant subclones in vivo and in vitro in Ph-positive ALL.

A leukemia line KOPN30bi was established from a patient with acute lymphocytic leukemia (ALL) and Philadelphia (Ph) chromosome. The clonal rearrangement of the immunoglobulin heavy chain (IgH) gene and the expression of the P190 type BCR/ABL chimeric transcript were shown to be identical between KOPN30bi and the predominant clone (S1) in the blast cell population from which KOPN30bi was established, indicating that they are of the same clonal origin. Studies of the T-cell antigen receptor (TCR) gene configuration including the TCR beta, gamma, and delta loci showed that none of them was identical between KOPN30bi and S1. The TCR delta region was rearranged on both of the alleles in KOPN30bi and was deleted on both alleles in S1 indicating that KOPN30bi was not derived from S1. Polymerase chain reaction analysis, using an oligonucleotide probe corresponding to the N region sequence of the V gamma-J gamma juncture of KOPN30bi, indicated that only 0.1% of the blast cells corresponded to KOPN30bi. Thus molecular diversification of dominant subclones in vivo and in vitro was shown in Ph-positive ALL.

Base Sequence↗
PubMed1996

Evidence for oligoclonal diversification of the VH6-containing immunoglobulin repertoire during reconstitution after bone marrow transplantation.

Patients who have undergone bone marrow transplantation (BMT) remain immunodeficient for months to years posttransplantation. To evaluate the basic molecular events underlying reconstitution of the humoral immune response, we have performed a detailed nucleotide sequence analysis of VH6 containing rearrangements in circulating B cells from two BM donor/recipient pairs. Our results show that the third complementarity determining region (CDR3) diversity is much lower early after transplantation, compared with that of the donors, and that the clonal variability remains low for 3 months. Repertoire diversification follows an oligoclonal pattern where B lymphopoiesis appears to occur in waves up to 6 months posttransplantation. The repertoire among donated marrow cells is not reflected in peripheral blood lymphocytes from the transplanted patients. There is differential D gene utilization among both donor and patient samples, whereas JH gene usage is biased toward JH4, 5, and 6. One month after transplantation the vast majority of the sequenced clones are functional and contain a high frequency of replacement mutations in the CDRs of the VH6 gene. We conclude that Ig gene expression is very restricted early after BMT and that development of the B-cell repertoire appears to follow a wavelike pattern.

Adult↗
PubMed1995

T cell reconstitution by haploidentical BMT does not restore the diversification of the Ig heavy chain gene in patients with X-linked SCID.

We previously examined the Ig heavy (H) chain gene of pretransplant patients with X-linked SCID (XSCID), having defects in the gene of the IL-2 receptor (R) gamma chain. In the present study, we analyzed two post-transplant XSCID patients, in whom T cell-depleted haploidentical BMT resulted in lymphoid split chimeras, i.e., donor functional T cells coexisting with recipient B cells. Although the recipient B cells produced IgM, no isohemagglutinin or Ag-specific Ab was detected. To investigate the cause of failure to produce Ab in the patients, we sequenced the complementarity determining region 3 (CDR3) and adjacent region of Ig H chain gene, which govern Ab specificity. Among the 64 post-transplant CDR3 junctional sequences, combinatorial and junctional diversity were normal compared with those in age-matched controls. All of the post-transplant joining regions except one clone were equal to germline and the frequency of somatic mutation was significantly lower than that in age-matched controls. The results indicated that T cell reconstitution by BMT does not restore diversification of the Ig gene in the IL-2R gamma chain-deficient B cells, which might be associated with the defect in the Ag-specific Ab production.

Base Sequence↗
PubMed1998

Lack of intraclonal diversification in Ig heavy and light chain V region genes expressed by CD5+IgM+ chronic lymphocytic leukemia B cells: a multiple time point analysis.

To analyze the modalities of clonal expansion of chronic lymphocytic leukemia (CLL) cells, we sequenced at multiple time points the V(D)J genes expressed by CD5+IgM+CLL B cells in three patients. All three V(D)J gene sequences were found to be point mutated. The mutation frequency in the Ig VH (3.96 x 10(-2) and 2.41 x 10(-2) change/bp) and Vkappa and Vlambda (6.67 x 10(-2) and 1.74 x 10(-2) change/bp) genes of two CLLs (1.19 and 1.32, respectively) was similar, and higher than that in the corresponding gene segments of the third CLL (1.69; 3.4 x 10(-3) and 6.67 x 10(-3) change/bp). In all three CLLs, there was no preferential representation of nucleotide changes yielding amino acid replacement (R mutations), nor was there any preferential segregation of R mutations within the Ig V gene complementarity-determining regions. In all three CLLs, the somatic mutations were all identical in multiple Ig VHDJH transcripts at any given time point, and were all conserved at multiple time points throughout a 2-yr period. The lack of concentration of R mutations in the complementarity-determining regions and the lack of intraclonal heterogeneity suggest that Ag may no longer be able to play a significant role in the clonal expansion of these cells. This conclusion would be strengthened further by the germline configuration of the bcl-1 and bcl-2 proto-oncogenes that are translocated in neoplastic B cells that display significant traces of intraclonal diversification and Ag-dependent selection, such as B-prolymphocytic leukemia and low grade follicular non-Hodgkin lymphoma.

Aged↗
PubMed1998

Matrix metalloproteinases: structures, evolution, and diversification.

A comprehensive sequence alignment of 64 members of the family of matrix metalloproteinases (MMPs) for the entire sequences, and subsequently the catalytic and the hemopexin-like domains, have been performed. The 64 MMPs were selected from plants, invertebrates, and vertebrates. The analyses disclosed that as many as 23 distinct subfamilies of these proteins are known to exist. Information from the sequence alignments was correlated with structures, both crystallographic as well as computational, of the catalytic domains for the 23 representative members of the MMP family. A survey of the metal binding sites and two loops containing variable sequences of amino acids, which are important for substrate interactions, are discussed. The collective data support the proposal that the assembly of the domains into multidomain enzymes was likely to be an early evolutionary event. This was followed by diversification, perhaps in parallel among the MMPs, in a subsequent evolutionary time scale. Analysis indicates that a retrograde structure simplification may have accounted for the evolution of MMPs with simple domain constituents, such as matrilysin, from the larger and more elaborate enzymes.

Amino Acid Sequence↗