Patterns and significance of CD44 expression in lung allografts.

BACKGROUND: Lung allograft rejection involves the interplay of multiple cellular populations, soluble mediators, and extracellular matrix proteins. The CD44 family of cell surface glycoproteins mediates a variety of cell-cell and cell-matrix interactions including lymphocyte homing to sites of antigenic challenge and fibroblast migration and invasion into extracellular matrix, processes integral to lung allograft rejection. METHODS: We performed immunohistochemical staining for CD44 on biopsies from allograft recipients with differing rejection experiences: Group 1 (n = 5 patients/10 biopsies) never exceeded Grade A1 or B2 acute rejection (AR); Group 2 (n = 7 patients/26 biopsies) had 2 or more episodes of Grade A2 or higher AR and no obliterative bronchiolitis (OB); Group 3 (n = 6 patients/17 biopsies) had clinical and pathologic OB. Nine infected allograft biopsies, 8 near-normal lung sections (non-transplant controls), and 13 non-transplant biopsies showing bronchiolitis obliterans organizing pneumonia (BOOP), organizing diffuse alveolar damage (DAD), or usual interstitial pneumonia (UIP) were also studied. RESULTS: Allograft biopsies demonstrated significantly more CD44 staining among lymphocytes, macrophages, Type II pneumocytes, and respiratory epithelial cells than non-transplant controls, while staining of lymphocytes, macrophages, and Type II pneumocytes did not differ significantly between allograft groups. Fibroblast CD44 staining in Group 3 biopsies significantly exceeded that of controls and Groups 1 and 2, and biopsies with AR and/or OB showed more fibroblast staining than biopsies with BOOP, organizing DAD, or UIP. Alveolar CD44-positive fibroblasts did not predict development of OB, while bronchial CD44-positive fibroblasts were followed in one case by OB. CONCLUSIONS: These findings suggest that CD44 expression is characteristic of graft-infiltrating inflammatory cells and resident parenchymal cells, and may be related to the initiation and evolution of AR and OB.

Parental behavior after perinatal death: twelve years of observations.

Perinatal death is a tragic occurrence, and parents vary in their needs and how they express grief. This prospective study describes choices parents made regarding contact with their baby following stillbirth or immediate neonatal death. Between 1 January 1979 and 1 March 1991, 808 consecutive families were enrolled in the Perinatal Mortality Counseling Program at the University of Florida. Following perinatal death, most parents wanted contact with their baby to personalize the event, information about the death and follow-up from their health care providers. However, no option was chosen by all parents. This large study strongly supports offering choices to all parents. Providers should neither bias parents nor make presumptions that would limit parental choices.

Distribution of heterotopic neurons in normal hemispheric white matter: a morphometric analysis.

One of the frequent abnormalities described in the context of surgically resected temporal lobe (TL) specimens is the presence of heterotopic neurons within white matter (WM). We have attempted to morphometrically define the distribution of the heterotopic neurons in normal subjects, comparing the incidence of heterotopic neurons in TL WM with that in occipital (OL) and frontal lobe (FL) sections. Using a a combination of routine and special stains combined with immunohistochemical confirmation 20 adult autopsy cases were examined. WM from TL, FL, and Ol sections was outlined and the area measured by image analysis. Using defined criteria, heterotopic neurons within these areas were counted. Results confirm our hypothesis that normal adult TL WM contains a significantly higher population of residual/heterotopic neurons than OL and FL WM groups. It is felt that these neurons represent interstitial remnants of the subplate which have failed to undergo programmed cell death. The significance of these findings with regard to assessment of similar findings in temporal lobectomy specimens is addressed. A second intriguing association of this TL WM heterotopia concerns its possible relationship to the more frequent occurrence of ¿malformative neoplasms¿ with neuronal elements (such as ganglioglioma and dysembryoplastic neuroepithelial tumor) in the temporal lobe.

Flow cytometry. In vitro assessment of its potential application for diagnosis and classification of lymphoid processes in cytologic preparations from fine-needle aspirates.

Detection and accurate classification of lymphoid processes in fine-needle aspirate specimens can be a challenging task for the pathologist. Recognizing the usefulness of flow cytometric methods for the diagnosis of lymphoproliferative disorders (LPDs), the authors applied flow cytometric analysis to 38 tissue samples that had a possible diagnosis of LPD and to fine-needle aspiration-derived cytologic preparations. Four aspirations from each sample provided from .44 x 10(6) to more than 70 x 10(6) cells in total. The highest yields were associated with low-grade B-cell non-Hodgkin's lymphomas (NHLs). Washing cytologic preparation cell suspensions did not enhance diagnostic ability and dramatically reduced cell counts (average decrease, 79.8%), potentially problematic with small samples. Comparison of ploidy, S fraction, and immunophenotypic data from the cytologic preparations and cell suspensions made from the conventionally processed parent tissues indicates that cytologic preparation composition closely parallels the tissue of origin. A multiparametric flow cytometric technique used to enhance detection of B-cell clonal expansions allowed for successful recognition of 17 of 21 (81%) B-cell NHLs in cytologic preparations, with false-negative results primarily reflecting a lack of viable tumor cells in the cytologic preparation cell suspensions. A T-cell NHL and a nonhematopoietic malignancy were also identified in cytologic preparations. None of the benign conditions were interpreted as lymphoma. Flow cytometric techniques applied to fine-needle aspirates of lymphoid processes yield important diagnostic information, which may be maximized by adaptations in processing and flow cytometric analysis.

A SNOMED analysis of three years' accessioned cases (40,124) of a surgical pathology department: implications for pathology-based demographic studies.

Pathology departments devote considerable energy toward indexing diagnoses. To date, there have been no detailed tabulations of the results of these efforts. We have thoroughly analyzed three years' surgical pathology reports (40,124) generated for 29,127 different patients from the University of Florida at Gainesville between Jan 1, 1990, and December 31, 1992. 64,921 SNOMED code entries (averaging 1.6 codes per specimen and 1.4 specimens per patient) were accounted for by 1,998 distinct SNOMED morphologies. A mere 21 entities accounted for 50% of the morphology code occurrences. 265 entities accounted for 90% of the morphology code occurrences, indicating that the diagnostic efforts of pathology departments are contained within a small fraction of the many thousands of morphologic entities available in the SNOMED nomenclature. One of the key problems in using SNOMED data collected from surgical pathology reports is the redundancy of lesions reported for single patients (i.e., a patient's disease may be coded on more than one specimen from the patient, leading to false conclusions regarding the incidence of disease in the population). In this study, redundant SNOMED data was removed by eliminating repeat morphology/topography pairs whenever they occur for a single patient. SNOMED data can be stratified on the basis of age and sex (data fields included on every surgical pathology report). This analysis represents the first published analysis of SNOMED data from a large pathology service, and demonstrates how SNOMED data can be compiled in a form that preserves patient privacy.

Daily stress and recurrence of genital herpes simplex.

It is widely believed that emotional stress triggers recurrences of both oral and genital herpes simplex virus. On a daily basis, we studied 64 subjects prospectively for 1 to 3 months; all subjects had at least one culture-proved recurrence of genital herpes simplex virus type 2 before or during the study. All subjects filled out a questionnaire that measured psychological/emotional stress in six areas: physical health, relations with friends, relations with family, relations with sex partner(s), financial, and vocation/education. These questionnaires were mailed back to us daily. Data were analyzed by General Linear Models analysis of variance to compare stress reported on each of the 6 days before a recurrence with that on days during or after a recurrence, as well as days not temporally related to recurrence. Under these conditions, in which retrospective bias was minimized, there was no significant increase in psychological/emotional stress on any day in any area preceding a recurrence of genital herpes simplex virus.

A PC-based free text retrieval system for health care providers. Design and development.

The purpose of this paper is to describe the design and development of the Clinical Practice Library of Medicine (CPLM). CPLM is an investigational project aimed at providing health care practitioners with critical in-depth information similar to that obtained from a medical reference library or consultant. When used in conjunction with the physician's knowledge, CPLM can provide valuable diagnostic prompting information to assist in rapidly reaching a suitable diagnosis for timely administration of appropriate treatment. This system may also be used to assist paramedical professionals working in remote areas where other expert medical assistance may not be available.

A PC-based free text DSS for health care. Case studies and applications.

A free text decision support system (DSS) has been constructed for health care professionals that allows the analysis of complex medical cases and the creation of a diagnostic list of potential diseases for clinical evaluation. The system uses a PC-based text management system specifically designed for desktop operation. The texts employed in the decision support package include The Merck Manual (published by Merck Sharpe & Dohme) and Control of Communicable Diseases in Man (published by the American Public Health Association). The background and design of the database are discussed, along with a structured analysis procedure for handling free text DSS systems. A case study is presented to show the application of this technology and conclusions are drawn in the summary that point to expanded areas of professional interaction and new frontiers yet to be explored in this rapidly progressing field.

Diagnostic library support system for medical practice.

Here is a tragic case where the diagnosis was missed on three separate occasions over a 19-month period. Both terminal conditions are treatable and potentially separable if discovered and aggressively managed. It is not the intent of this presentation to criticize the evaluation of this patient, but rather to point out the need and, also, the potential benefits of an alternate approach, which could have significantly changed the course of this particular patient's evaluation. We have conducted similar analyses with other CPC cases with almost equivalent specificity. These same evaluations have been performed in a real clinical setting with live patient data. What we have learned so far we think will be extremely helpful in extending the potential application of this technology: A text-based decision support tool is only as good as its practitioner. It takes practice and training to learn to use this system effectively. There are many traps in logic, and the use of words and terms within the text must be understood to effectively utilize this tool. There are shortcuts in logical analysis which we mentally use all the time but which cannot be accepted using this system (e.g., you must not rely on your memory or any specific associations to circumvent the system). The system will only become clinically relevant when the entire field of medicine is included in the data base. This is one of our current limitations with only two-thirds of the Merck medical text available for reference. This makes it difficult to apply to a general medical problem since we are not sure which direction the case might take, and often these are multisystem diseases or problems that put us at a severe disadvantage if we don't have the necessary data base. The structure and integrity of the data base are critical to the success of the system. Since numbers are ubiquitous, these cannot be used for key word elements. Techniques must be introduced to create word-oriented numbers that can be uniquely identified (e.g., "AGE14-20"). The publisher of the data must supply a continuous flow of up-to-date material that can be incorporated within the framework of the working system. It is possible to train medical technicians to use the system if they are familiar with medical terminology. The speed and, perhaps, the precision of their analysis could not be expected to rival that of a medical specialist.(ABSTRACT TRUNCATED AT 400 WORDS)

Uninterruptible power systems and other power protection equipment for electronic health care systems.

The increasing usage of electronic instruments in health care systems invariably leads to some level of dependence on them. In order to maximize the utility of these tools a high degree of reliability is essential. Many of the failures being experienced in systems where electronic instruments are being utilized may be attributed not to a failure of the instrument itself but rather to the poor quality of the commercial power to which they are attached. In order to reduce the effects of power fluctuations and outages, some type of power protection equipment must be installed between the commercial power system and the instrument. This article discusses the types of "electronic noise" present on commercial power lines and the various types of equipment used to reduce its effect on electronic instrumentation. In general, the Uninterruptible Power System (UPS) is shown to be the most effective power buffering element for a health care environment. General terminology associated with specifications of a UPS is defined in the article and attached appendix.