A polymeric form of fibronectin has antimetastatic effects against multiple tumor types.

Metastasis accounts for most deaths in cancer patients. Tumor cell adhesion to the extracellular matrix through integrins is thought to be a critical step in metastasis and a potential target for therapeutic intervention. We show here that treatment of human osteosarcoma, melanoma and carcinoma cells with a polymeric form of fibronectin (sFN), before inoculation into nude mice, prevented tumor formation. Intraperitoneally administered sFN significantly reduced lung colonization from intravenously injected tumor cells (experimental metastasis) and from subcutaneous tumors in nude mice (spontaneous metastasis). Treatment with sFN blocked cell spreading and migration in vitro suggesting a possible mechanism for the antimetastatic effect.

Very late activation antigens (VLA) are human leukocyte-neuronal crossreactive cell surface antigens.

The antigenic relationship between human neuronal and lymphocyte cell surface antigens has been analyzed using heteroantisera raised against human peripheral blood mononuclear cells (PBMC). The specificities of the crossreactive antigens were examined by immunoprecipitation of 125I-labeled SK-N-SH cultured neuronal cells using rabbit anti-PBMC (RAPBMC) sera and compared to known specificities using mAb. The predominant reactivity of each rabbit antiserum tested against SK-N-SH cells was with three molecules of 130,000, 160,000, and 180,000 Mr. These three chains comigrated with three molecules precipitated with the very late activation antigen (VLA)-specific mAb A-1A5. Sequential precipitations with mAb A-1A5 established that the three RAPBMC-precipitated bands were members of the VLA complex. This was confirmed by two-dimensional PAGE of the RAPBMC and A-1A5 immunoprecipitates, which were indistinguishable from one another. The two-dimensional pattern was more complex than was anticipated from the heterodimeric model of VLA chain association, and suggests an additional 130,000 Mr component of VLA. The three chains of the VLA complex precipitated by RAPBMC or mAb A-1A5 from SK-N-SH neurons closely resembled the VLA pattern present on activated T cells, including the 180,000 Mr activation-specific alpha 1 chain recognized by mAb TS2/7. Normal brain cell membranes also contain VLA molecules that are precipitated by RAPBMC and mAb A-1A5. Thus the VLA complex provides potentially important shared immunogens on human neurons and T cells.

Augmentation of in vitro humoral immune responses in the mouse by an antibody to IgD.

Heterologous anti-delta-chain antibodies have an adjuvant effect on specific in vivo humoral immune responses to simultaneously, or subsequently, injected antigens in the rat and rhesus monkey. We have used a hybridoma-secreted antibody that binds murine delta-chain of the allotype (4.22aM delta a) to study this phenomenon in the mouse and to investigate the mechanism of this effect. Injection of 4.22aM delta a into BALB/c mice removes almost all surface IgD (sIgD) from splenic B lymphocites. sIgD does not reappear until the serum level of 4.22aM delta a decreased 5-7 d after injection. 4.22aM delta a fails to induce detectable proliferation or to raise total serum Ig levels substantially above control values. However, 4.22aM dalta a injected 24 h before antigen elicits an approximately twofold enhancement of serum IgM and a 3- to 10-fold enhancement of serum IgG anti-trintriphenyl (TNP) antibodies in response to immunization with optimal doses of TNP-Ficoll or TNP-sheep red blood cells (TNP-SRBC). 4.22aM delta a injected 1 wk before or 3 d after TNP-SRBC, however, has no effect on IgG anti-TNP levels. The adjuvant effect of anti-delta-chain antibody was markedly decreased when suboptimal antigen doses were used. Furthermore, even in the case of TNP-Ficoll, a relatively T-independent antigen, the ability of 4.22aM dalta a to enhance the anti-TNP antibody response was T cell dependent. Our data suggest that the binding of anti-delta-chain antibody to cell sIgD may partially activate B lymphocytes and make them more capable of differentiating into antibody-secreting cells when stimulated by antigen-specific T cell help.

Migration of noble gas tracers at the site of an underground nuclear explosion at the Nevada National Security Site.

As part of an underground gas migration study, two radioactive noble gases (37Ar and 127Xe) and two stable tracer gases (SF6 and PFDMCH) were injected into a historic nuclear explosion test chimney and allowed to migrate naturally. The purpose of this experiment was to provide a bounding case (natural transport) for the flow of radioactive noble gases following an underground nuclear explosion. To accomplish this, soil gas samples were collected from a series of boreholes and a range of depths from the shallow subsurface (3 m) to deeper levels (~160 m) over a period of eleven months. These samples have provided insights into the development and evolution of the subsurface plume and constrained the relative migration rates of the radioactive and stable gas species in the case when the driving pressure from the cavity is low. Analysis of the samples concluded that the stable tracer SF6 was consistently enriched in the subsurface samples relative to the radiotracer 127Xe, but the ratios of SF6 and 37Ar remained similar throughout the samples.

Evaluation of the OSOM Trichomonas rapid test versus wet preparation examination for detection of Trichomonas vaginalis vaginitis in specimens from women with a low prevalence of infection.

The OSOM Trichomonas rapid test (OSOM Trich) was compared to the wet preparation examination (WP) for the detection of Trichomonas vaginalis vaginitis in women with a low prevalence of infection. A total of 19/1,009 (2%) women had T. vaginalis infection. OSOM Trich had very good performance, with sensitivity, specificity, efficiency, positive predictive value, and negative predictive value of 94.7, 100, 99.9, 100, and 99.9%, respectively. The implementation of OSOM Trich would decrease labor costs.

Platelet glycoproteins Ia, Ic, and IIa are physicochemically indistinguishable from the very late activation antigens adhesion-related proteins of lymphocytes and other cell types.

The very late activation antigens (VLA) are a subset of the superfamily of cell surface glycoproteins that serve as receptors from extracellular matrix proteins. One or more of the VLA heterodimers are present on T lymphocytes and most other cell types, including platelets. We have used VLA-specific monoclonal antibodies to isolate the reactive platelet membrane molecules. We have identified them as previously characterized platelet surface glycoproteins and have compared them with VLA molecules isolated from lymphocytes and other cells. Utilizing one-dimensional SDS-PAGE, two-dimensional O'Farrell gel electrophoresis, and nonreduced-reduced two-dimensional gel electrophoresis, we show that reduced VLA molecules of platelets are composed of three chains of molecular weights 165,000, 145,000, and 140,000 that possess the physicochemical properties of platelet glycoproteins GPIa, GPIc alpha, and GPIIa. GPIa corresponds to the VLA 165,000 alpha 2-chain, GPIIa corresponds to a 145,000 Mr VLA beta-chain, and GPIc alpha corresponds to a 140,000 Mr VLA alpha-chain. The polypeptide structure of VLA molecules on platelets and lymphocytes are very similar or identical. Platelet proteins GPIa and GPIIa exist as a mixed heterodimer in detergent lysates and correspond with the VLA-2 heterodimer found on activated T lymphocytes and other cell types. The platelet glycoproteins GPIIa and GPIc form a second mixed heterodimer. The mAb A-1A5, which binds to the VLA beta chain, binds to platelet GPIIa and precipitates both the GPIIa-GPIa and GPIIa-GPIc heterodimers, and binds to 4,926 +/- 740 sites per platelet. A VLA-2-specific mAb, 12F1, which binds to the VLA alpha 2-chain reacts with GPIa and immunoprecipitates only the GPIIa-GPIa heterodimer, and binds to 1,842 +/- 449 sites per platelet. The similarity of VLA chains and platelet GPIIa, GPIa, and GPIc molecules suggests that these molecules may have similar functions on various cell types.

Antigenic polymorphism of human very late activation protein-2 (platelet glycoprotein Ia-IIa). Platelet alloantigen Hca.

We have found evidence for a human alloantigenic system on the very late activation protein -2 (VLA-2) heterodimer (platelet GPIa/IIa). Sera from two patients with systemic lupus erythematosus (SLE) contained antibodies that immunoprecipitated surface molecules from platelets and fibroblasts that comigrated on SDS-PAGE and two-dimensional O'Farrell gels with platelet GPIa (VLA-alpha2 chain) and platelet GPIIa (VLA-beta chain). These SLE antibodies were alloreactive as they precipitated VLA molecules from only 5 of 22 normal donors' platelets and did not react with the lupus patients' own platelets, despite the expression of apparently normal amounts of VLA on the donors' cells. Two-dimensional O'Farrell analysis demonstrated no differences in the molecular weight or isoelectric point of GPIa and GPIIa obtained from platelets of alloantibody reactive or unreactive donors. Sequential immunoprecipitation experiments with VLA chain-specific monoclonal antibodies, and the pattern of immunoprecipitation of several different VLA heterodimers demonstrated that the alloantibody-reactive determinant was present on the VLA-2 heterodimer, and not other VLA molecules. Thus, these SLE sera demonstrate a previously unrecognized antigenic polymorphism of the VLA-2 (platelet GPIa/IIa) heterodimer, platelet alloantigen Hca.

Polymorphism of lymphocyte function-associated antigen-1 demonstrated by a lupus patient's alloantiserum.

We have found a human serum, E27, obtained from a multiply transfused patient with systemic lupus erythematosus, which immunoprecipitates the lymphocyte function associated antigen-1 (LFA-1). The immunoprecipitated molecules were identified as the LFA-1 alpha and beta chains by their comigration on SDS-PAGE, two-dimensional SDS-PAGE, and by sequential clearance experiments. Serum E27 did not immunoprecipitate LFA-1 from autologous cells, though LFA-1 molecules were present. In contrast, serum E27 immunoprecipitated LFA-1 from most but not all normal donor lymphocytes. Thus, serum E27 defines two serological phenotypes of LFA-1. 95% of normal individuals tested exhibited the LFA-1 phenotype precipitated by serum E27. Serum E27 appears to be directed at determinants of the LFA-1 alpha-chain and not the beta-chain since it immunoprecipitated LFA-1 molecules but not the Mac-1 molecules. Additional evidence for the alpha chain specificity was provided by immunoprecipitation of mouse-human heterohybridoma cells. LFA-1 was immunoprecipitated by serum E27 from mouse-human heterohybridoma cells expressing the human alpha-chain, not from a hybrid cell line expressing the human beta-chain. Together these findings demonstrate an antigenic polymorphism of the human LFA-1 alpha-chain molecule.

Social ecological predictors of prostate-specific antigen blood test and digital rectal examination in black American men.

BACKGROUND: Black American men continue to suffer disproportionately from epidemically higher rates of prostate cancer. We hypothesize that complex reasons for persistently higher death rates of prostate cancer in this group are steeped in social factors associated with health access. METHODS: We utilized data from the It's All About U prostate cancer prevention study among black men to investigate: 1) what social ecological factors were predictive of prostate-specific antigen (PSA) testing and digital rectal examinations (DRE); 2) if black men were aware of prostate cancer screening and, if screening was available, would they take the PSA and DRE? Quantitative cross-sectional data from a cohort of 276 black men with no diagnosis of prostate cancer were analyzed to identify characteristics, beliefs, practices and attitudes of this group toward prostate cancer screening. We created a social ecological model to examine which social factors (i.e., environmental, personal, person/environment interplay, black culture and institutional policy) were predictive of PSA and DRE, PSA only and DRE only. To reduce data and identify data patterns, factor analyses (tested for reliability by calculating Cronbach alpha scores) were performed. Variables were standardized with Z scores and analyzed with predictive analytic software technology (SPSS, version 12). A multivariate binary logistic regression was conducted to identify predictors of PSA and DRE. RESULTS: A significant predictor of both PSA and DRE was the physician's direct prostate cancer communication message (P<0.010). Significant correlations exist in PSA and DRE outcomes with a physician's engaging communication style (P<0.012), encouragement to screen (P<0.001) and sharing prostate cancer information (P<0.001); as was men understanding the serious risk of prostate cancer (P<0.001), culture (P<0.004), positive interaction with healthcare staff, significant other(s) and providers (P<0.001), and environmental dimensions (P<0.006). A profile of four major self-reported barriers to screening were identified (i.e., fear, internal locus of health, comfort level and external locus of health). Lastly, men who utilized health systems with a prostate cancer screening policy had high percentages of PSA and DRE (63.3%), PSA only (70.9%) and DRE only (81.7%). CONCLUSION: A physician's aggressive, positive engagement in shared decision-making, tailored social influences promoting prostate cancer prevention among black men, as well as institutional screening policy, has the potential to increase early detection and reduce morbidity among this group.

Development of a novel spontaneous metastasis model of human osteosarcoma transplanted orthotopically into bone of athymic mice.

There is a pressing need for in vivo models in which potential antitumor agents can be tested for their ability to inhibit the growth and metastatic spread of human sarcomas. A recent advance in this regard has been the development of a v-Ki-ras-oncogene-transformed human osteosarcoma cell line (KRIB) that efficiently colonizes the lungs of athymic nude mice when cells (1 x 10(5)) are administered by i.v. injection. In the present study, we have utilized this cell line to develop a spontaneous metastasis model in which a small number of tumor cells are injected into the tibial bones of athymic mice. When as few as 1000 KRIB cells are orthotopically implanted into the tibial bones of nude mice, bone tumors, which are radiographically and histologically similar to primary human osteosarcoma, develop within 4 weeks. Furthermore, as in the human disease, cells from these primary tumors subsequently seed the animals' lungs, resulting in reproducible and quantifiable pulmonary metastasis evident both upon gross inspection of the lungs and histologically 6 weeks after tumor inoculation. Surgical amputation of the tumor inoculation site up to 2 weeks after tumor injection prevents pulmonary metastasis, indicating that substantial local (tibial) growth and invasion of the primary tumor for at least 2 weeks is required for subsequent metastasis. Implantation of s.c. 5000 KRIB cells fails to produce local or metastatic tumors. We anticipate that this model will prove to be a powerful tool with which to study the mechanisms of human osteosarcoma growth and pulmonary metastasis, and to assess the efficacy of promising therapeutic agents.

Anticardiolipin antibodies from patients with the antiphospholipid antibody syndrome recognize epitopes in both beta(2)-glycoprotein 1 and oxidized low-density lipoprotein.

BACKGROUND: We recently suggested that many anticardiolipin antibodies bind only to oxidized cardiolipin (OxCL) and/or to OxCL-beta(2)-glycoprotein 1 (beta(2)GP1) adducts but not to a "reduced" cardiolipin that is unable to undergo oxidation. To test this hypothesis, we investigated 24 sera, 4 protein A-purified IgG fractions, and 3 human monoclonal antibodies that were all isolated from patients with antiphospholipid antibody syndrome (APS); testing was also performed in 7 controls. Two monoclonal antibodies (IS3 and IS4) were selected for binding to CL and one was selected for binding to beta(2)GP1 (LJB8). METHODS AND RESULTS: By chemiluminescent immunoassay, all APS sera samples bound only to OxCL and not to reduced CL, and the binding was inhibited >95% by OxCL but not reduced CL. All purified IgG fractions bound to beta(2)GP1 but only when the beta(2)GP1 was plated on microtiter wells coated with OxCL. All 3 monoclonal antibodies bound only to OxCL. On Western blots, IS4 and LJB8 bound to beta(2)GP1 as well as to delipidated apoB of oxidized LDL but not to native apoB. IS3 also bound to oxidized apoB on Western blot. Covalent modification of beta(2)GP1 with oxidation products of CL made it more antigenic for APS serum samples, for purified IgG fractions, and for the monoclonal antibodies. CONCLUSIONS: These data support the hypothesis that oxidation of CL is needed to generate epitopes for many anticardiolipin antibodies and that some of these epitopes are covalent adducts of OxCL with beta(2)GP1 or apoB.

Mutants of Saccharomyces cerevisiae resistant to the alpha mating-type factor.

Mutants that are resistant to alpha-factor have been isolated from a mating-type haploid strains of yeast by direct selection on agar medium containing partially purified alpha-factor. All resistant mutants isolated were found to be sterile. They were characterized and compared with mutants previously isolated as non-mating. Among 93 able to mate at low frequency and to sporulate, none showed linkage to the mating-type locus. The results support the hypothesis that the response to alpha-factor by cells of mating-type a is essential for mating.

Expression and ligand binding of alpha 2 beta 1 integrin on breast carcinoma cells.

We examined the expression and ligand specificity of the alpha 2 beta 1 integrin on human mammary epithelial cells (HMEC) and a panel of breast carcinoma cell lines in vitro. We found that the alpha 2 beta 1 integrin was universally, but quite variably expressed on these cells by FACS analysis. No significant correlation was observed between its expression and other known cellular phenotypes. Substrate attachment assays using blocking antibodies demonstrated that alpha 2 beta 1 integrin served as a receptor for collagen on HMEC and almost all breast carcinoma cells. However, its contribution to laminin binding of these cells appeared to be related to cellular differentiation as evaluated by sex steroid receptor status and by markers of epithelial-mesenchymal transition, i.e. loss of E-cadherin and expression of vimentin. Two different populations of non-malignant immortalized HMEC (184A1N4 and MCF-10A) contained cells capable of using alpha 2 beta 1 integrin as a laminin receptor. Breast cancer cell lines positive for estrogen receptor (ER) and E-cadherin (MCF-7, T47D, ZR75-1) could also use alpha 2 beta 1 integrin as a laminin receptor. Conversely, alpha 2 beta 1 integrin appeared to be incapable of binding to laminin or to be a very minor receptor for laminin on metastatic ER-negative breast carcinoma cells that expressed vimentin (MDA-MB 231, MDA-MB 435, and MDA-MB 436). These findings suggest that the ligand specificity of alpha 2 beta 1 integrin, i.e. its function as a laminin receptor, may be regulated during the malignant progression of breast carcinoma cells. A reduced contribution of alpha 2 beta 1 integrin to the cellular laminin binding appears to be associated with an increased malignant phenotype and with an epithelial-mesenchymal transition of breast carcinoma cells.

Discrimination between innate and cytophilic immunoglobulin on human peripheral blood lymphocytes: analysis by the direct antiglobulin rosette-forming reaction.

Bovine red blood cells linked to polyclonal or monoclonal anti-immunoglobulin antibodies are used in the direct antiglobulin rosetting reaction to detect surface-Ig on human lymphocytes. The sensitivity of this test is markedly increased by pretreating the red cells with trypsin. Enzyme-treated red cells, coupled to anti-human Fab or anti-light chain antibodies, react not only with innate Ig on B lymphocytes but also with smaller amounts of passively adsorbed, cytophilic Ig on up to 25% of freshly prepared peripheral blood (non-B) lymphocytes. In contrast, trypsinized red cells carrying anti-Ig isotype-specific antibodies react exclusively with B cell surface-Ig. Cytophilic Ig is abnormally firmly bound to lymphocytes separated on Ficoll-Hypaque at 20 degrees C or below, and is released very slowly during 3 h or more at 37 degrees C in vitro. Lymphocytes are free of detectable cytophilic Ig when isolated on Ficoll-Hypaque at 37 degrees C, and very little Ig is retained by non-B cells in suspensions purified on Percoll which, unlike Ficoll, does not increase Ig binding affinity. These lymphocyte separation procedures are recommended as a preliminary to B cell assays by sensitive antiglobulin techniques.

Tritium (3H) radiolabeling of protein A and antibody to high specific activity: application to cell surface antigen radioimmunoassays.

Staphylococcal protein A and several different immunoglobulins have been radiolabeled to high specific activities (greater than 10(6) cpm/microgram) by reductive methylation with tritiated (3H) sodium borohydride. The proteins retain excellent functional and antigenic properties. The utility of these reagents in a variety of assays for cell surface antigens is illustrated. The results indicate that this radiolabeling procedure may become the method of choice for many cell surface and solution immunoassays.

Peripheral blood mononuclear cell-endothelial adhesion in human hypertension following exercise.

OBJECTIVE: To determine the effects of hypertension and exercise on interleukin-6 (IL-6) levels and mononuclear cell adhesion to endothelial cells. DESIGN: Twelve hypertensive and 33 normotensive volunteers were studied prior to and following exhaustive exercise. End points were stimulated IL-6 levels and peripheral blood mononuclear cell (PBMC) CD11a (LFA-1) expression and in vitro PBMC adhesion to human umbilical venous endothelial cells (HUVEC). RESULTS: In response to exercise, all subjects showed a significant increase in lymphocyte CD11a a density and in IL-6 levels (P < 0.001). Compared to normotensives, hypertensives showed significantly greater mean density of CD11a on lymphocytes (P< 0.05) and on monocytes (P < 0.05). In response to exercise, hypertensive subjects showed a twofold greater increase in IL-6 as compared to normotensives (+ 240 pg/ml versus + 123 pg/ml, respectively; P< 0.05). PBMC adhesion to HUVEC was increased in hypertensives but decreased in normotensives following exercise (P< 0.03). CONCLUSION: The findings suggest that exercise leads to increased mononuclear cell adhesion to endothelial cells in patients with hypertension, possibly through cytokine-induced activation of mononuclear cell CD11a. These findings, coupled with prior data indicating increased endothelial activation in hypertension, may be relevant to the increased risk of atherosclerosis in human hypertension.

Improved resolution of fibronectin mRNA expression in the inner ear using laser scanning confocal microscopy.

We describe a modified in situ hybridization protocol for localizing and quantifying fibronectin gene expression at the cellular level in paraffin sections of rat temporal bone. When combined with a novel analytical approach using laser scanning confocal microscopy (LSCM), this protocol significantly improved the resolution, sensitivity, and specificity of existing procedures for evaluating fibronectin synthesis in developing inner ear. For simultaneous viewing of cochlear anatomy and the autoradiographic signal, transmitted light images of the cochlea were collected separately from LSCM reflected light images of the autoradiographic silver grains and then the two images were electronically merged. Within the first 2 microns below the surface of the emulsion, silver grains were clustered specifically over hybridized cells. In contrast, nonspecific silver grain development (i.e., background noise) was confined primarily to the lower 5 microns of the emulsion adjacent to the tissue section. Limiting the volume of the emulsion examined in the LSCM analysis, i.e., restricting the range of optical sectioning to the first 2 micron below the surface of the emulsion, effectively minimized nonspecific background noise and maximized the specificity of the hybridization signal. The improvements offered by the described methodological approaches are equally appropriate for non-calcified tissues.

The frequency of homozygous deletion of a developmentally regulated Vh gene (Humhv3005) is increased in patients with chronic idiopathic thrombocytopenic purpura.

Little is known of the genetic factors that may contribute to the development of chronic idiopathic thrombocytopenic purpura (cITP). We have previously shown that a developmentally regulated Vh gene (Humhv3005) is absent in 10/41 (24%) of patients with systemic lupus erythematosus while it is absent in only 7/88 (8%) of normal controls. This finding suggests that a homozygous deletion of an Ig variable (V) gene may alter the immune system and thus predispose the host to an autoimmune disorder. We have analyzed the same gene in 44 patients with cITP and found that Humhv3005 and like genes were absent in a higher percentage of patients (14 of 44, 31.8%) than they were absent in either normals (7/88, 8%, p = 0.002) or thrombocytopenic patients without cITP (6/53, 11.3%, p = 0.042); the hv3005 deletion frequency in the latter group did not differ from that in normals (P = 0.74). These data suggest that deletions of Humhv3005 and/or highly homologous Vh genes may predispose individuals to the development of cITP, and may contribute toward production of pathogenic antiplatelet antibodies.

Wound closure with human keratinocytes cultured on a polyurethane dressing overlaid on a cultured human dermal replacement.

BACKGROUND: Burn excision followed by immediate wound coverage has become the clinical standard for managing extensive burn injuries in much of the world. When sufficient autograft skin to achieve permanent wound closure is unavailable, cell culture technology has made the use of cultured human keratinocyte (HK) sheets clinically feasible. Whereas previous techniques have focused on development of multilayered, differentiated HK sheets, our attention has been drawn to using HK in a highly proliferative, less differentiated state. Time requirements for preparation of multistratified cultured HK are high, and preparatory steps may destroy important integrin adhesion molecules. METHODS: We describe the use of HK cultured to single layer confluence on a polyurethane membrane(HD), with serum-free medium. HK-HD grafts were transplanted to full-thickness wounds on athymic mice (n = 31). A second group of mice (DG-HK-HD), n = 28) received a living human dermal replacement containing cultured fibroblasts before placement of HK-HD. Control mice received HD alone (n = 4). Basement membrane proteins on healed wounds and surface integrins on cultured HK were identified by means of immunostaining and direct microscopic visualization. RESULTS: HK cultured just to the confluent state on polyurethane membrane were positive for integrins alpha(5) and alpha(6), major integrins on proliferating HK. Histologic analysis showed epithelialized wounds in all groups after 21 days. Using an anti-human involucrin antibody we demonstrated the presence of HK in 64.5% of the HK-HD group, 61% of the DG-HK-HD group, and 0% in the HD group. Mice that received the living human dermal replacement containing cultured fibroblasts in combination with HK-HD grafts developed a thick, well-vascularized neodermis. Strong laminin and collagen IV staining was observed in wound areas covered with HK. CONCLUSIONS: These data show that full-thickness wounds can be closed by application of a single layer of proliferating HK cultured on a biocompatible polyurethane membrane. This technique is an alternative to the use of multilayered, differentiated HK sheets. Preparation times for HK-HD grafts should be significantly shorter than required for multilayered HK sheets, technical efforts should be less, and more extensive wound areas could be covered.

Culture, black men, and prostate cancer: what is reality?

BACKGROUND: The worldwide incidence of prostate cancer is higher among American black men than any other male group. In the United States, lack of participation in screening for prostate cancer by black men is influenced by several cultural factors, including knowledge, health beliefs, barriers, and relationships with primary healthcare providers. METHODS: We used the qualitative and paralleling descriptive quantitative findings of a mixed-method longitudinal study exploring prostate cancer screening behaviors among 277 black men. RESULTS: Five themes were identified as critical elements affecting men's screening for prostate cancer: lack of knowledge, communication, social support, quality of care, and sexuality. These themes were associated with a sense of disconnectedness by black men from the healthcare system and contributed to nonparticipation in prostate cancer early detection activities. CONCLUSIONS: Lack of discussion about the decision to screen for prostate cancer and general lack of culturally appropriate communication with healthcare providers has engendered distrust, created fear, fostered disconnect, and increased the likelihood of nonparticipation in prostate cancer screening among black men.