Sexually transmitted infections: Prevalence and clinical outcomes among pregnant women in Western Sydney

OBJECTIVE

We report the prevalence, characteristics and clinical outcomes of women with sexually transmitted infections (STIs) in pregnancy in the Western Sydney Local Health District (WSLHD) serving a large culturally and socio-economically diverse community in New South Wales (NSW), Australia, over the last 10 years.

METHODS

A retrospective cohort study of all pregnant women booked for antenatal care at three hospitals in WSLHD between September 2012 and August 2022 inclusive. Characteristics and birth outcomes associated with STIs diagnosed in pregnancy (chlamydia, gonorrhea, and syphilis) are reported using multivariable logistic regression adjusting for relevant confounders.

RESULTS

During 2012-2022, there were 102 905 births and 451 women (0.44%) with an STI diagnosis during pregnancy. The number of women with a history of chlamydia prior to their current pregnancy has increased over the last 10 years (P < 0.001). STIs in pregnancy were more common in younger women aged <20 years (adjusted odds ratio [aOR] 7.30, 95% confidence interval [CI] 5.04-10.57), 20-24 years (aOR 3.12, 95% CI 2.46-3.96), and >40 years (adj OR 1.67, 95% CI 1.07-2.59), in women with body mass index >30 (aOR 1.73, 95%CI 1.37-2.19), and those who smoked (aOR 2.24, 95% CI 1.71-2.94) and consumed alcohol (aOR 3.14, 95% CI 1.88-5.23) and illicit drugs (aOR 2.10, 95% CI 1.31-3.36). STIs in pregnancy were borderline associated with stillbirth (aOR 2.19 95% CI 0.90-5.36) but did not have a significant impact on preterm birth (aOR 1.21, 95% CI 0.87-1.68), admission to neonatal intensive care unit (NICU) (aOR 1.02, 95% CI 0.77-1.34), or having a small-for-gestational-age (SGA) baby (aOR 0.97, 95% CI 0.74-1.27).

CONCLUSIONS

Sociodemographic factors such as age, weight, smoking, and alcohol and drug use, were associated with the STI incidence in pregnancy. While the latter did not have an impact on preterm birth, NICU admission, and SGA in our cohort, there was a borderline association with stillbirth. Future research should identify barriers and facilitators to testing in a multicultural population and understanding the drivers of higher rates of STIs in certain population groups.

Ambulatory Care Coordination Data Gathering and Use

Care coordination is a crucial component of healthcare systems. However, little is known about data needs and uses in ambulatory care coordination practice. Therefore, the purpose of this study was to identify information gathered and used to support care coordination in ambulatory settings. Survey respondents (33) provided their demographics and practice patterns, including use of electronic health records, as well as data gathered and used. Most of the respondents were nurses, and they described varying practice settings and patterns. Although most described at least partial use of electronic health records, two respondents described paper documentation systems. More than 25% of respondents gathered and used most of the 72 data elements, with collection and use often occurring in multiple locations and contexts. This early study demonstrates significant heterogeneity in ambulatory care coordination data usage. Additional research is necessary to identify common data elements to support knowledge development in the context of a learning health system.

Knowing the Patient: Understanding Readmission Reasons in Complex Heart Failure

BACKGROUND

Heart failure (HF) is a complex problem characterized by frequent hospitalizations and high 30-day readmission rates. Researchers studying HF readmission report that patients and clinicians have different perspectives on readmission and preventability when unadjusted for disease severity.

OBJECTIVE

The aim of this study was to gather patient, caregiver, nurse, and physician subjective reason(s) for 30-day HF readmission and perceptions of preventability with contextual factors to evaluate differences.

METHODS

A convergent, parallel, mixed-methods design was used with interviews and chart reviews to evaluate contextual factors from the current and index hospital stay. Adults readmitted within 30 days of a previous inpatient stay with a coded HF diagnosis were enrolled and interviewed, followed by interviews with associated caregivers, attending physicians, and assigned nurses.

RESULTS

Interviews were conducted with patients (n = 44), caregivers (n = 6), physicians (n = 24), and nurses (n = 44). Readmissions were emergent/urgent (95%) and occurred within 14.9 days (SD, 8.1; 2-28 days) on average after discharge. Index stay coding revealed that most patients (73%) had a high severity of illness (73%) and risk of mortality (68%). Heart failure stage was inconsistently documented. Patients reported acute symptomatic reasons, with only 32% describing readmission as preventable. Physicians reported diagnostic reasons, 38% of which were preventable. Nurses reported behavioral reasons, with 59% being preventable. Patient/clinician agreement on readmission reason was low (30%).

CONCLUSIONS

Patient/clinician perspectives on readmission varied among the patients with complex HF. Care planning based on HF stage and other contextual factors is needed to ensure a shared understanding of disease severity and a tailored symptom management approach to prevent readmission.

Information Models Offer Value to Standardize Electronic Health Record Flowsheet Data: A Fall Prevention Exemplar

PURPOSE

The rapid implementation of electronic health records (EHRs) resulted in a lack of data standardization and created considerable difficulty for secondary use of EHR documentation data within and between organizations. While EHRs contain documentation data (input), nurses and healthcare organizations rarely have useable documentation data (output). The purpose of this article is to describe a method of standardizing EHR flowsheet documentation data using information models (IMs) to support exchange, quality improvement, and big data research. As an exemplar, EHR flowsheet metadata (input) from multiple organizations was used to validate a fall prevention IM.

DESIGN

A consensus-based, qualitative, descriptive approach was used to identify a minimum set of essential fall prevention data concepts documented by staff nurses in acute care. The goal was to increase generalizable and comparable nurse-sensitive data on the prevention of falls across organizations for big data research.

METHODS

The research team conducted a retrospective, observational study using an iterative, consensus-based approach to map, analyze, and evaluate nursing flowsheet metadata contributed by eight health systems. The team used FloMap software to aggregate flowsheet data across organizations for mapping and comparison of data to a reference IM. The FloMap analysis was refined with input from staff nurse subject matter experts, review of published evidence, current documentation standards, Magnet Recognition nursing standards, and informal fall prevention nursing use cases.

FINDINGS

Flowsheet metadata analyzed from the EHR systems represented 6.6 million patients, 27 million encounters, and 683 million observations. Compared to the original reference IM, five new IM classes were added, concepts were reduced by 14 (from 57 to 43), and 157 value set items were added. The final fall prevention IM incorporated 11 condition or age-specific fall risk screening tools and a fall event details class with 14 concepts.

CONCLUSION

The iterative, consensus-based refinement and validation of the fall prevention IM from actual EHR fall prevention flowsheet documentation contributes to the ability to semantically exchange and compare fall prevention data across multiple health systems and organizations. This method and approach provides a process for standardizing flowsheet data as coded data for information exchange and use in big data research.

CLINICAL RELEVANCE

Opportunities exist to work with EHR vendors and the Office of the National Coordinator for Health Information Technology to implement standardized IMs within EHRs to expand interoperability of nurse-sensitive data.

A refined methodology for validation of information models derived from flowsheet data and applied to a genitourinary case

Use of electronic health record data is expanding to support quality improvement and research; however, this requires standardization of the data and validation within and across organizations. Information models (IMs) are created to standardize data elements into a logical organization that includes data elements, definitions, data types, values, and relationships. To be generalizable, these models need to be validated across organizations. The purpose of this case report is to describe a refined methodology for validation of flowsheet IMs and apply the revised process to a genitourinary IM created in one organization. The refined IM process, adding evidence and input from experts, produced a clinically relevant and evidence-based model of genitourinary care. The refined IM process provides a foundation for optimizing electronic health records with comparable nurse sensitive data that can add to common data models for continuity of care and ongoing use for quality improvement and research.

Validation of Stroke Network of Wisconsin Scale at Aurora Health Care System

BACKGROUND

The Stroke Network of Wisconsin (SNOW) scale, previously called the Pomona scale, was developed to predict large-vessel occlusions (LVOs) in patients with acute ischemic stroke (AIS). The original study showed a high accuracy of this scale. We sought to externally validate the SNOW scale in an independent cohort.

METHODS

We retrospectively reviewed and calculated the SNOW scale, the Vision Aphasia and Neglect Scale (VAN), the Cincinnati Prehospital Stroke Severity (CPSS), the Los Angeles Motor Scale (LAMS), and the Prehospital Acute Stroke Severity Scale (PASS) for all patients who were presented within 24 hours after onset at AHCS (14 hospitals) between January 2015 and December 2016. The predictive performance of all scales and several National Institute of Health Stroke Scale cutoffs (≥6) were determined and compared. LVO was defined by total occlusions involving the intracranial internal carotid artery, middle cerebral artery (MCA; M1), or basilar arteries.

RESULTS

Among 2183 AIS patients, 1381 had vascular imaging and were included in the analysis. LVO was detected in 169 (12%). A positive SNOW scale had comparable accuracy to predict LVO and showed a sensitivity of 0.80, specificity of 0.76, the positive predictive value (PPV) of 0.31, and negative predictive value of 0.96 for the detection of LVO versus CPSS ≥ 2 of 0.64, 0.87, 0.41, and 0.95. A positive SNOW scale had higher accuracy than VAN, LAMS, and PASS.

CONCLUSION

In our large stroke network cohort, the SNOW scale has promising sensitivity, specificity and accuracy to predict LVO. Future prospective studies in both prehospital and emergency room settings are warranted.

Abstract WP308: Low Volume of Acute Stroke Intervention in Aurora Health Care System Analysis

Introduction: Thrombectomy for acute ischemic stroke (AIS) is an important intervention, though the majority of eligible patients do not receive it. Drawing upon data from our high volume comprehensive stroke center, we identified barriers to recognizing patients with large vessel occlusion and subsequent impediments to treatment.

Methods: This is a retrospective chart review of patients presenting with AIS within 24 hours to the 14 hospitals within the AHCS between January 2015 and December 2016. Demographic, National Institutes of Health Stroke Scale (NIHSS) score, vascular imaging, and thrombectomy data were collected and analyzed. Large vessel occlusion (LVO) involved the distal internal carotid artery (ICA), middle cerebral artery (M1), or basilar artery (BA).

Results: Three thousand five hundred ninety- five AIS patients were identified. The median age was 61 years and 1863 (52%) were female. Two thousand one hundred eighty-three patients presented within 24 hours (61%): 1105 ≤ 6 hours. More than one third of AIS patients (773) did not have acute intracranial vascular imaging. Of 1410 patients with vascular imaging, 171 patients (12 %) had LVO. The site of occlusion was: M1, 86 patients (50.3%); distal ICA, 51 (30%); and BA, 27 (16%). Only 75 LVO patients (44%) had acute stroke intervention of whom 57 (77%) had mechanical thrombectomy, additional intra-arterial thrombolysis was given in 14 (19%) and 4 (5%) had intra-arterial thrombolysis as monotherapy. Successful revascularization (mTICI 2b-3) was achieved in 53 patients (70%). The main reasons that LVO patients did not receive acute stroke intervention include: late onset or unknown onset in 32 (35%), large core infarction 25 (27%), rapid improving NIHSS in 6 (7%), and unclear reason in 25 (17%),

Conclusion: There are several reasons that LVO is under recognized: a non neurologist often evaluates the patient in the ER first and they might not be familiar with stroke protocol guidelines; some LVO patients have an atypical presentation; and some patients refuse intervention. Based on our data, there is a need for continuing education of stroke care providers, particularly in this period of changing interventional guidelines.

Abstract WP216: External Validation of Pomona Large Vessel Occlusion Scale at Aurora Health Care System (AHCS)

Background: The Pomona scale was developed to predict large-vessel occlusions (LVO) in patients with acute ischemic stroke (AIS). The original study showed a high accuracy of this scale. We sought to externally validate the Pomona scale in an independent cohort.

Methods: Pomona scale includes 3 items: gaze deviation, expressive aphasia and neglect, each given 1 point when present. We retrospectively reviewed a large cohort of all acute stroke patients who presented within 24 hours after onset at AHCS ( 14 hospitals) between January 2015-December 2016. We calculated Pomona scale, the Vision Aphasia and Neglect Scale (VAN), the Cincinnati Prehospital Stroke Severity (CPSS), the Los Angeles Motor Scale (LAMS), the Prehospital Acute Stroke Severity Scale (PASS) for all patients. The predictive performance of all scales and several National Institute of Health Stroke Scale (NIHSS) cut offs (≥4, ≥6, ≥8, ≥10) were determined and compared. LVO was defined by total occlusions involving the intracranial internal carotid artery, middle cerebral artery (M1), or basilar arteries.

Results: Among 2183 AIS patients, 1410 had vascular imaging and were included in the analysis. LVO was detected in 171 (12%). Pomona scale ≥ 1 had comparable accuracy to predict LVO as Pomona scale ≥ 2, the CPSS, and NIHSS ≥6, ≥8, and ≥10. Pomona scale ≥ 1 had higher accuracy than VAN, LAMS, PASS and NIHSS ≥ 4 (area under the receiver operating characteristics curve: Pomona ≥ 1= 0.77 as a reference; VAN=0.66, P < 0.001; LAMS ≥ 4 = 0.61, P < 0.001, PASS ≥ 2= 0.68, P < 0.001 and NIHSS ≥ 4, P= 0.0025). A Pomona scale ≥ 1 had sensitivity of 0.79, specificity of 0.76 to predict LVO, positive predictive value of 0.31, and negative predictive value of 0.96 for the detection of LVO versus Pomona scale ≥ 2 of 0.57, 0.91, 0.47, and 0.94 and CPSS ≥ 2 of 0.64, 0.87, 0.41 and 0.95.

Conclusion: In our large stroke network cohort, the Pomona scale has promising sensitivity, specificity and accuracy to predict LVO. Future prospective studies in both prehospital and emergency room settings are warranted.

Harmonizing and extending standards from a domain-specific and bottom-up approach: an example from development through use in clinical applications

Objective Currently, the processes for harmonizing and extending standards by leveraging the knowledge within local documentation artifacts are not well described. We describe a collaborative project to develop common information models, terminology bindings, and term definitions based on nursing documentation systems, and carry the findings through to the adoption in standards development organizations (SDOs) and technical implementations in clinical applications.

Materials and Methods Nursing flowsheet documents from six large organizations were analyzed to generate a common information model and terminologies that fully expressed documentation across all systems, and were sufficient for evidence-based decision support, reporting, and analysis.

Results Significant gaps in existing standards were identified. The models and terminologies were submitted to and incorporated by SDOs, are published, implemented, and now serving as a foundation for an eMeasure.

Discussion There are few examples in the literature of success working through the standards development process from a bottom-up perspective. Subsequently, standards do not yet fully address the need for detailed clinical data that enables, for example, decision support as well as a range of reporting and analytic requirements. Recommendations from this project include transparent processes within SDOs, registries that make models and associated terminologies freely available, and coordinated governance processes.

Conclusion We demonstrated the feasibility of using documentation artifacts in a bottom-up approach to develop common models and sets of terms that are complete from the perspective of clinical implementation. Importantly, we demonstrated a process by which a community of practice can contribute to closing gaps in existing standards using SDO processes.

Substitution of Hospital Staff in Concurrent Utilization Review

Substitution of hospital staff performing concurrent utilization review (CUR) was evaluated using a production process framework. There were no differences in the number of reimbursement denials or denied days among 4 job classifications of hospital staff performing CUR, indicating that educational preparation of staff did not affect outcomes. The implications are that hospitals could substitute assistive staff in place of registered nurses to complete the CUR function, potentially increasing the availability of professional nurses.

Responses of hospital utilization review staff to reimbursement denials

Utilization review (UR) is a strategy used by the managed care industry to monitor and control utilization of health care resources. The concurrent UR process requires that hospital staff report clinical information to payers, who either certify or deny reimbursement. Conflicts may arise when hospital staff disagree with denial decisions. The authors analyzed the various responses of a medical center UR staff to payer denials and found that although denials were not frequent, they were perceived negatively by hospital staff. Improving and standardizing communication among providers, payers, and patients is one means of reducing conflict and frustration in the event of reimbursement denial.

Expression pattern and gene characterization of asporin. a newly discovered member of the leucine-rich repeat protein family

We have discovered a new member of the class I small leucine-rich repeat proteoglycan (SLRP) family which is distinct from the other class I SLRPs since it possesses a unique stretch of aspartate residues at its N terminus. For this reason, we called the molecule asporin. The deduced amino acid sequence is about 50% identical (and 70% similar) to decorin and biglycan. However, asporin does not contain a serine/glycine dipeptide sequence required for the assembly of O-linked glycosaminoglycans and is probably not a proteoglycan. The tissue expression of asporin partially overlaps with the expression of decorin and biglycan. During mouse embryonic development, asporin mRNA expression was detected primarily in the skeleton and other specialized connective tissues; very little asporin message was detected in the major parenchymal organs. The mouse asporin gene structure is similar to that of biglycan and decorin with 8 exons. The asporin gene is localized to human chromosome 9q22-9q21.3 where asporin is part of a SLRP gene cluster that includes extracellular matrix protein 2, osteoadherin, and osteoglycin. Further analysis shows that, with the exception of biglycan, all known SLRP genes reside in three gene clusters.

The fibronectin-binding MSCRAMM FnbpA of Staphylococcus aureus is a bifunctional protein that also binds to fibrinogen

Staphylococcus aureus is an important pathogen capable of causing a wide spectrum of diseases in humans and animals. This bacterium expresses a variety of virulence factors that participate in the process of infection. These include MSCRAMMs (microbial surface components recognizing adhesive matrix molecules) that mediate the adherence of the bacteria to host extracellular matrix components, such as collagen, fibronectin (Fn), and fibrinogen (Fg). Two Fn-binding MSCRAMMs, FnbpA and FnbpB, have been previously identified. The Fn binding activity has been localized to the approximately 40-amino acid residue D repeats in the C-terminal part of these proteins. However, no biological activity has yet been attributed to the N-terminal A regions of these proteins. These regions exhibit substantial amino acid sequence identity to the A regions of other staphylococcal MSCRAMMs, including ClfA, ClfB, and SdrG (Fbe), all of which bind Fg. This raises the question of whether the Fn-binding MSCRAMMs can also bind specifically to Fg. In this report, we show that a recombinant form of the A region of FnbpA does specifically recognize Fg. We localize the binding site in Fg for recombinant FnbpA to the gamma-chain, in particular to the C-terminal residues of this polypeptide, the site also recognized by ClfA. In addition, we demonstrate that recombinant FnbpA can compete with ClfA for binding to both immobilized and soluble Fg. By the use of surface plasmon resonance spectroscopy and fluorescence polarization, we determine the dissociation equilibrium constant for the interaction of recombinant FnbpA with intact immobilized Fg and with a synthetic C-terminal gamma-chain peptide, respectively. Finally, by overexpressing FnbpA in a mutant strain of S. aureus that lacks the expression of both ClfA and ClfB, we show that native FnbpA can mediate the interaction of S. aureus with soluble Fg.

Coordinating the care of the chronically ill in a world of managed care

The systems required to provide coordinated health care to the chronically ill within a managed care contract are complex. As an integrated health care delivery system assuming shared financial risk of enrollees in a Medicare + Choice contract, many care processes need to be created to meet the needs of the clients and administrators. Nursing case management and physician partnering are integral to the creation of the care model. The fiscal data demonstrated, for clients in this model, that there was an overall decrease in the inpatient length of stay, hospital days per thousand, and 30-day readmission rates.

Dermatomyositis associated with bronchiolitis obliterans organizing pneumonia (BOOP)

Bronchiolitis obliterans organizing pneumonia (BOOP) is rarely associated with dermatomyositis and may be resistant to conventional corticosteroid therapy under this circumstance. We present a case of BOOP associated with dermatomyositis that responded to a combination of cyclophosphamide and corticosteroid therapy after corticosteroid treatments, alone, had failed. We believe this case shows it is important to recognize that facial rash in the presence of respiratory distress may represent dermatomyositis with BOOP and aggressive treatment may be necessary for resolution of pulmonary symptoms.

Characterization of human DSPG3, a small dermatan sulfate proteoglycan

PG-Lb is a small dermatan sulfate proteoglycan that has been previously characterized in chicken. In the developing limb, chick PG-Lb appears to be exclusively expressed in the zone of flattened chondrocytes. We have cloned and sequenced the human homolog to chick PG-Lb from two human chondrocyte cDNA libraries and a human chondrocyte RNA sample. The human homolog has been named DSPG3, as it is the third member of the small dermatan sulfate proteoglycan family to be identified and characterized along with biglycan (PG-I) and decorin (PG-II). DSPG3 maps to chromosome 12q21 and is composed of 1515 nucleotides of cDNA that code for a 322-amino-acid protein. The protein contains three potential glycosaminoglycan attachment sites, two N-glycosylation sites, a poly- glutamic acid stretch, and six cysteines. By Northern analysis, we have demonstrated that DSPG3 is expressed in cartilage, as well as ligament and placental tissues.

An evaluation of the accuracy of residency applicants' curricula vitae: are the claims of publications erroneous?

Competition for residency positions in dermatology is intense. Training programs in other disciplines have described significant misrepresentation among their applicants in claims of research and publication. An evaluation was made of the curricula vitae for the 138 applicants with completed applications for our 1994 residency match. Cited articles were placed in four categories: "published," "in print/in press," "submitted for publication," and "in preparation/in progress." We found significantly less misrepresentation than has been described in other specialty training programs. Simplification of the way in which applicants verify their bibliography may reduce erroneous citations and remove implications of willful misrepresentation of academic achievements.

Protein kinase C phosphorylates two of the four known syndecan cytoplasmic domains in vitro

The transmembrane heparan sulfate proteoglycans of the syndecan family are implicated to participate in several cellular reactions which are dependent on protein kinase C. We have used an in vitro assay to assess whether any of the Peptides corresponding to the complete cytoplasmic domains of rat syndecans 1 through 4 were used as substrates for the enzyme. The syndecan-2 (fibroglycan) and syndecan-3 (N-syndecan) peptides were both found to be phosphorylated by protein kinase C with Kms of 15 +/- 3 microM and 85 +/- 25 microM, respectively, while the syndecan-1 and -4 peptides were not phosphorylated under the conditions used. The sites of in vitro phosphorylation for syndecans-2 and -3 were localized to ser-197 and ser-339, respectively. Thus, among 13 available sites (serines and threonines) in the four peptides, two were selectively modified by the enzyme. The specificity and the kinetics of the reactions indicate that the cytoplasmic domains of syndecan-2 and -3 are likely to be physiological substrates for protein kinase C.

Regulation of cell substrate adhesion: effects of small galactosaminoglycan-containing proteoglycans

Cell adhesion is a process which is initiated by the attachment of cells to specific sites in adhesive matrix proteins via cell surface receptors of the integrin family. This is followed by a reorganization of cytoskeletal elements which results in cell spreading and the formation of focal adhesion plaques. We have examined the effects of a class of small galactosaminoglycan-containing proteoglycans on the various stages of cell adhesion to fibronectin-coated substrates. Our results indicate that dermatan sulfate proteoglycans (DSPGs) derived from cartilage, as well as other related small proteoglycans, inhibit the initial attachment of CHO cells and rat embryo fibroblasts to substrates composed of the 105-kD cell-binding fibronectin fragment, but do not affect cell attachment to intact fibronectin. Although this effect involves binding of DSPGs to the substrate via the protein core, the intact proteoglycan is necessary for the observed activity. Isolated core proteins are inactive. The structural composition of the galactosaminoglycan chain does not appear to be functionally significant since both chondroitin sulfate and various dermatan sulfate proteoglycans of this family inhibit cell attachment to the fibronectin fragment. Neither the percentage of cells spread nor the mean area of spread cells adhering to substrates of intact fibronectin was significantly affected by the DSPGs. However, significantly fewer cells formed focal adhesions in the presence of DSPGs as compared with untreated control cells. These results suggest that the binding of small galactosaminoglycan-containing proteoglycans to a fibronectin substrate may affect several stages in the cell adhesion process.

Collagen gel contraction by cells associated with proliferative vitreoretinopathy

The capacities of porcine choroidal fibroblasts, retinal glial cells, and retinal pigment epithelial cells to contract collagen gels in vitro were compared. Experiments with varied cell numbers indicated that glial cells are the most effective, followed by choroidal fibroblasts and retinal pigment epithelial cells. Analysis of the secretory products from cultures of these cell types revealed that retinal pigment epithelial cells synthesize and secrete peptides that promote fibroblast contraction of collagen gels in vitro. The mechanism of action of the retinal pigment epithelial cell-secreted contraction promoter was compared with that found in serum (type A) and secreted by cultured endothelial cells (type B). Like the serum factor, the retinal pigment epithelial cell-secreted factor was not dependent on active protein synthesis by the target cell and must be present continuously to promote contraction.

Molecular cloning of a novel hyaluronan receptor that mediates tumor cell motility

A cDNA encoding a unique hyaluronan receptor has been molecularly cloned from a lambda GT11 3T3 cDNA expression library. Immunoblot analyses of cell lysates, using antibodies to peptides encoded in the cDNA, specifically react with a 58-kD protein. This protein is regulated by the mutant H-ras gene in cells containing a metallothionein promoter H-ras hybrid gene. Further, antibodies to peptide sequences encoded in the cDNA block the increase in locomotion resulting from induction of the mutant H-ras gene in this cell line. In a transblot assay, the bacterially expressed protein binds to biotinylated hyaluronan. Antibodies to peptides encoded in the cDNA react in immunoblot assays with the 58- and 52-kD proteins of a novel hyaluronan receptor complex previously implicated in cell locomotion. Furthermore, antibodies specific to the 58- and 52-kD proteins, which block ras-induced locomotion, also cross-react with the expressed, encoded protein. The gene product described here appears to be a new type of hyaluronan receptor that is involved in cell locomotion. It is named RHAMM, an acronym for receptor for hyaluronan-mediated motility.

Binding of the proteoglycan decorin to collagen type VI

We have examined the interactions between the small dermatan sulfate proteoglycan decorin and collagen types I-VI using solid phase binding assays. The results of these studies showed that 125I-decorin bound most efficiently to collagen type VI in a time- and concentration-dependent manner. Furthermore, this interaction was specific and of moderately high affinity (Kd approximately 3 x 10(-7) M). Binding of decorin to collagen type VI appears to involve the decorin core protein rather than the glycosaminoglycan side chains, since the isolated core protein as well as a recombinant fusion protein containing a major segment (65%) of the human decorin core protein inhibited binding of 125I-decorin to collagen type VI. Other related proteoglycans and their respective core proteins also inhibited the binding of 125I-decorin to collagen type VI, whereas unrelated proteins and isolated glycosaminoglycan chains were without effect. In addition to decorin, collagen type II was also shown to bind to immobilized collagen type VI. Both interactions were effectively inhibited by preincubation of the immobilized collagen VI with decorin or collagen type II. These results suggested that the collagen type VI molecule has binding sites for collagen type II and decorin which are located in close proximity on the collagen type VI molecule. Possible functional roles of these interactions are discussed.

Endothelins produced by endothelial cells promote collagen gel contraction by fibroblasts

Endothelial 1 (E1) is identified as an endothelial cell secreted factor that stimulates collagen gel contraction by fibroblasts. This identification is based on (a) co-localization of stimulatory activity in endothelial cell conditioned media with synthetic E1 in reversed phase analysis; (b) removal of the activity from conditioned media with antiserum directed against E1; and (c) the activity of synthetic E1. Treatment of endothelial cell conditioned media with immobilized anti-E1 antibodies removed 59% of the activity from the pool suggesting that E1 is the major contraction promoter in endothelial cell conditioned medium. The mechanism of action of E1 is shown to be different from serum in that E1-promoted contraction is dependent upon the synthesis of an unknown effector protein. Synthetic E1 is shown to be a potent promoter of gel contraction with half-maximal activity occurring at 32 pM. Two other endothelins, E2 and VIC, are slightly less active than E1. A fourth endothelin species, E3, is substantially less active. A comparison of E1 with other contraction promoting peptides revealed that E1 and platelet-derived growth factor are essentially equal in specific activity, whereas TGF beta is approximately 50-fold more potent.

Identification of Porphyromonas gingivalis components that mediate its interactions with fibronectin

Porphyromonas (Bacteroides) gingivalis W12 binds and degrades human plasma fibronectin. In the presence of the protease inhibitor N-alpha-p-tosyl-L-lysyl chloromethyl ketone, P. gingivalis cells accumulated substantial amounts of 125I-fibronectin as a function of incubation time. Fibronectin binding was specific, reversible, and saturable. The Kd for the reaction was estimated to be on the order of 100 nM, and there was an average of 3.5 x 10(3) fibronectin binding sites per cell. Unlabeled fibronectin inhibited the binding of 125I-fibronectin to bacteria; however, fibrinogen was an even more efficient inhibitor of 125I-fibronectin binding. Unrelated proteins were without effect on fibronectin binding. A fibronectin-binding component (Mr, 150,000) was identified in sodium dodecyl sulfate-solubilized P. gingivalis. Fibronectin was degraded into discrete peptides by P. gingivalis W12. The degradation of fibronectin was inhibited by N-alpha-p-tosyl-L-lysyl chloromethyl ketone. Two P. gingivalis components (Mrs, 120,000 and 150,000) degraded fibronectin in substrate-containing gels following sodium dodecyl sulfate-polyacrylamide gel electrophoresis. In a previous study (M. S. Lantz, R. D. Allen, T. A. Vail, L. M. Switalski, and M. Hook, J. Bacteriol. 173:495-504, 1991), we found that the same strain of P. gingivalis bound and subsequently degraded human fibrinogen via apparently distinct cell surface components of molecular sizes similar to those of components now implicated in the binding and degradation of fibronectin. These results raise the possibility that the two ligands are recognized and modified by the same components on P. gingivalis W12. In support of this hypothesis, unlabeled fibrinogen effectively inhibited the binding of 125I-fibronectin to bacteria and blocked 125I-fibronectin binding to a P. gingivalis ligand-binding component (Mr, 150,000 immobilized on a nitrocellulose membrane.

A second fibronectin-binding region is present in collagen alpha chains

The interactions of plasma fibronectin with alpha chains or cyanogen bromide fragments of collagen types I and II have been studied using a variety of techniques. Affinity chromatography of cyanogen bromide-cleaved type II collagen on immobilized fibronectin revealed the binding of cyanogen bromide fragment CB12 in addition to the previously characterized CB10. Using fluorescence polarization, we analyzed the interaction between the collagen peptides and fluorescein isothiocyanate-labeled 42-kDa gelatin-binding fragment of fibronectin in solution. Dissociation constants for the binding of CB10 and CB12 to the fibronectin fragment were calculated as 0.38 and 0.94 microM, respectively, indicating a lower affinity for the uncharacterized site. However, as with CB10, CB12 was able to compete effectively with the intact alpha chain for bindinng to fibronectin. Additionally, both CB10 and CB12 absorbed to tissue culture surfaces were each able to support fibronectin-dependent cell adhesion. Finally, the regions of alpha 2(I) homologous to CB12 and CB10 were found to be active in fibronectin binding, demonstrating the presence of two fibronectin-binding regions in this collagen chain.

Peptide analogs to a fibronectin receptor inhibit attachment of Staphylococcus aureus to fibronectin-containing substrates

Binding of cells of Staphylococcus aureus to fibronectin has been proposed as a mechanism of bacterial adhesion to host tissues. In this study, we have attempted to define the role of a recently identified fibronectin receptor in the adhesion of staphylococcal cells to fibronectin-containing substrates by using different receptor analogs as potential inhibitors of bacterial adherence. The results showed that synthetic peptides D1, D2, and D3, corresponding to variations of a repeated unit in the fibronectin-binding domain of the receptor, and ZZ-FR, a chimeric protein containing the fibronectin-binding domain of the receptor with the D1, D2, and D3 sequences, inhibited the attachment of staphylococcal cells to microtiter wells coated with intact fibronectin or with the 29-kilodalton amino-terminal fragment of fibronectin. The chimeric protein ZZ-FR also partially inhibited the adherence of staphylococci to human plasma clots formed in vitro but had no effect on bacterial adhesion to clots formed from fibronectin-depleted plasma. These data confirm previous reports suggesting that fibronectin may serve as a substrate for adhesion of staphylococcal cells and indicate that bacterial adhesion is mediated by the identified fibronectin receptor. Furthermore, analogs to the fibronectin receptor can be used to inhibit the adhesion of bacterial cells to these model substrates, and these analogs may be of clinical use.

Endothelial cells secrete a factor that promotes fibroblast contraction of hydrated collagen gels

Bovine aortic endothelial cells (BAEC), grown in vitro, are shown to synthesize and secrete factor(s) that stimulate fibroblasts to contract collagen matrices. The amount of contraction-promoting activity in the conditioned media is dependent on conditioning time and the number of cells in the culture. Production of the contraction-promoting activity continues at a high stable level for at least 5 d in serum-free medium but is abolished when the cells are exposed to an inhibitor of protein synthesis. The mechanism of action of the contraction factor(s) derived from endothelial cells was compared with that of unidentified serum factors. The endothelial cell-secreted factor(s) depends on active protein synthesis by the target cell but does not need to be present during the contraction process. The serum factors on the other hand promote collagen contraction in the absence of de novo protein synthesis but need to be continuously present. Preliminary biochemical characterization of the contraction-promoting factors produced by endothelial cells revealed properties similar to those of previously identified growth factors. However, the BAEC-secreted factor was found to be distinct from a previously identified contraction-promoting transforming growth factor beta.

Critical care voices: including sexual counseling in clinical practice

We asked four practicing critical care nurses for tips on how they include sexual counseling in their practice with MI patients and families. Each one has developed a different, but effective, approach.

Staphylococcal adhesion to collagen in intra-articular sepsis

Ultrastructural studies of the cartilaginous articular surfaces of human and rabbit joints have shown that cartilage is the target substratum for adhesion by Staphylococcus aureus, leading to intra-articular sepsis. Transmission and scanning electron microscope studies demonstrated bacteria in intimate contact with acellular cartilage matrix surfaces, particularly with collagen fibres. Certain strains of Staphylococcus aureus used in these experiments reveal a high binding capacity to collagen that is derived from a cartilage matrix. These studies indicate that the pathogenesis of intra-articular sepsis is based on the ability of certain strains of staphylococci to bind preferentially to a cartilage matrix.

Reduced sulfation of liver heparan sulfate in experimentally diabetic rats

Analyses by anion exchange chromatography indicate that heparan sulfate proteoglycans isolated from the livers of experimentally diabetic rats have a reduced net negative charge as compared with heparan sulfate proteoglycans from control rats. In contrast, the size of the normal and diabetic proteoglycans are indistinguishable as are the size of individual polysaccharide chains when compared by gel chromatography. The reduced net negative charge of heparin sulfate from diabetic rats is shown to be caused by a reduced number of sulfate groups present in the diabetic heparan sulfate. Results are presented suggesting that one of the biosynthetic enzymes; the N-deacelylase, which tentatively has been identified as a regulatory enzyme affecting the sulfate content of the polysaccharide chains, may be inhibited in the diabetic rat.