Class I and II HLA antigens in British patients with oral lichen planus

The frequencies of human leukocyte antigens--HLA-A, HLA-B, HLA-C, HLA-DR, and HLA-DQ1--were determined in a group of 40 white British patients with oral lichen planus and compared with those of healthy controls. Alterations in the frequencies of several HLA antigens were noted. In particular, an increase in HLA-Bw57 and a decrease in the frequency of HLA-DQ1 were seen in the group with lichen planus. When different clinical subgroups of lichen planus were compared with the control group, significant changes were also noted in the frequencies of HLA antigens. This suggests that lichen planus may represent a heterogeneity of diseases and that HLA-Bw57 may predispose a person to lichen planus whereas HLA-DQ1 may be associated with resistance to it.

Nursing research conventions: objectivity or obfuscation?

This paper is a critique of naïve realism, the philosophy which animates much nursing research, and which leads researchers to assume that the attainment of objective knowledge is possible. The nature of naïve realism, and its relationship to objectivity, is discussed. Central to this outlook is the belief that the values and interests of the researcher can and should be divorced from the prosecution of research. This is reflected in the literary convention of referring to the researcher in the third person. Contrary to this position, I argue that the interpretations, values and interests of the researcher are central to the research process. Moreover, nursing research may be affected by the interests of managers, educationalists, and those who wish to see nursing attain professional status. Nursing researchers should accept that they are part of the social situations which they study. They should therefore become reflexive in their outlook. This entails recognizing and attempting to understand the effects of the researcher, rather than trying to eliminate or ignore them.

Development of Monoclonal Antibodies for an Assay of Cardiac Troponin-I and Preliminary Results in Suspected Cases of Myocardial Infarction

To improve the specificity of biochemical markers of myocardial infarction (MI), we have developed a double monoclonal "sandwich" enzyme immunoassay to measure cardiac troponin-I (cTnI) in serum. We produced eight IgG monoclonal antibodies against human cardiac troponin-I (cTnI) and tested them against human and animal (canine, bovine, and rabbit) troponins. Five antibodies were cardiac-specific; none of the antibodies were species-specific. Two of the five cTnI-specific monoclonal antibodies were utilized in an immunoassay. Standards were made by adding purified human cTnI to affinity-stripped cTnI-free human sera to cover the range 0-100 micrograms/L for cTnI. The dose-response curve was nonlinear but reproducible. Total assay imprecision (CV) varied between 11% and 21%. The upper limit of the reference range (nonparametric 95% interval) was established as 3.1 micrograms/L by measuring cTnI concentration in sera of 159 hospitalized patients without evidence of cardiac disease. Purified human skeletal TnI up to 10,000 micrograms/L did not affect the assay (calculated cross-reactivity < 0.1%). Diagnostic sensitivities of creatine kinase MB isoenzyme (CK-MB) and cTnI were evaluated retrospectively in 49 consecutive patients with proven MI. In the 30 patients for whom sufficient information was available to establish an accurate time course, CK-MB was more sensitive during the first 4 h after the onset of chest pain, but thereafter the sensitivities were similar up to 48 h. However, cTnI is more cardiac-specific than is CK-MB and remains increased longer than does CK-MB.

Development of monoclonal antibodies for an assay of cardiac troponin-I and preliminary results in suspected cases of myocardial infarction

To improve the specificity of biochemical markers of myocardial infarction (MI), we have developed a double monoclonal "sandwich" enzyme immunoassay to measure cardiac troponin-I (cTnI) in serum. We produced eight IgG monoclonal antibodies against human cardiac troponin-I (cTnI) and tested them against human and animal (canine, bovine, and rabbit) troponins. Five antibodies were cardiac-specific; none of the antibodies were species-specific. Two of the five cTnI-specific monoclonal antibodies were utilized in an immunoassay. Standards were made by adding purified human cTnI to affinity-stripped cTnI-free human sera to cover the range 0-100 micrograms/L for cTnI. The dose-response curve was nonlinear but reproducible. Total assay imprecision (CV) varied between 11% and 21%. The upper limit of the reference range (nonparametric 95% interval) was established as 3.1 micrograms/L by measuring cTnI concentration in sera of 159 hospitalized patients without evidence of cardiac disease. Purified human skeletal TnI up to 10,000 micrograms/L did not affect the assay (calculated cross-reactivity < 0.1%). Diagnostic sensitivities of creatine kinase MB isoenzyme (CK-MB) and cTnI were evaluated retrospectively in 49 consecutive patients with proven MI. In the 30 patients for whom sufficient information was available to establish an accurate time course, CK-MB was more sensitive during the first 4 h after the onset of chest pain, but thereafter the sensitivities were similar up to 48 h. However, cTnI is more cardiac-specific than is CK-MB and remains increased longer than does CK-MB.

Spontaneous malignant transformation of melanocytes explanted from Wf/Wf mice with a Kit kinase-domain mutation

The W/Kit mouse locus, affecting proliferation and survival of pigment cells, blood cells, and germ cells, is known to encode a tyrosine kinase growth factor receptor and is considered a protooncogene; yet it has not heretofore been causally implicated in any malignancies of those cells. The Wf/Wf mutant mouse coat comprises viable and inviable melanoblast clones, seen ultimately as pigmented and white transverse stripes--the latter more prominent. Judging from the pattern, all clones initially expand, and the inviable ones then undergo programmed cell death prenatally. To observe skin melanocytes of the viable clones during extended proliferation, the cells were explanted from individual young mice. An unusually large number of primary explants failed to survive--a result consistent with a growth handicap. In 3 of the 10 surviving cell lines, many cells spontaneously underwent a series of striking changes with the classic features of transformation. The two transformed lines that have been tested by grafting to immunosuppressed hosts formed undifferentiated invasive tumors compatible with malignant amelanotic melanoma. None of our 52 other melanocyte lines of the coisogenic wild-type strain and 13 other natural genotypes have become transformed under the same culture conditions. Molecular analysis of the Wf gene revealed a single change from wild-type: a point mutation affecting the catalytic region in the kinase domain of the Kit protein. The apparent growth disadvantage due to the mutation may allow selection for melanocytes mobilizing more efficient pathways, thus leading to neoplasia. Production of both viable and inviable melanoblast clones is unlikely to be due only to the kinase mutation; possibly the degree, duration, and consistency of expression of this locus may be controlled by cis elements outside the coding region.

Effect of rapid thoracic compression on the cerebral blood flow-velocity patterns of small infants

We measured the middle cerebral artery (MCA) flow-velocities of 12 small infants (mean weight, 2,882 +/- 602 g) before, during, and after the rapid thoracic compression (RTC) maneuvers of partial forced expiratory flow-volume studies. Cerebral flow-velocities were measured using transcranial Doppler ultrasonography. RTC increased MCA end diastolic flow-velocities and Pourcelot indices of all infants (P less than 0.001). These values returned to baseline immediately after the release of chest compression. We also measured the MCA flow-velocities of several preterm infants during their normal daily activities. The changes in flow-velocity patterns observed during normal daily life were similar to those observed during RTC. These findings demonstrate that RTC produces real, but likely not pathologic, changes in cerebral blood flow-velocities.

Surveillance of nosocomial infection in private psychiatric hospitals: an exploratory study

BACKGROUND

The vast majority of work published about infection control programs, procedures, and practices addresses general acute care facilities. Consequently, infection-control coordinators at psychiatric hospitals have few established norms or models to use in adapting available standards to the unique needs of psychiatric hospitals and their patients. This descriptive study explored practices for the surveillance of nosocomial infections in private psychiatric hospitals.

METHODS

A survey was mailed to the infection control coordinator of the 284 hospitals belonging to the National Association of Private Psychiatric Hospitals. Questionnaire data were collected anonymously. Surveys were returned by 103 (36%) of the hospitals.

RESULTS

The most frequent criteria used to define the presence of nosocomial infections were the Center for Disease Control guidelines and clinical judgment, used by 38% and 39% of the respondents, respectively. Most (64%) of the respondents indicated that they did calculate a nosocomial infection rate. The most frequent method used to calculate infection rates was based on patient discharges. Sixty-five hospitals (63%) reported their most recent yearly infection rate, which ranged from 0.00 to 0.35, with a median rate of 0.05 (mean, 0.06; SD, 0.07).

CONCLUSIONS

Overall, the findings reflected much variability in respondents' practices in defining nosocomial infections and calculating infection rates. We therefore suggest that both the method used to calculate the rate and facilities' definitions of nosocomial infection be considered when comparing infection rates across facilities.

The poverty of professionalization: a critical analysis of strategies for the occupational advancement of nursing

The purpose of this paper is to evaluate critically the strategies of occupational advancement used by nurses. It is noted that these are frequently framed within the paradigm of professionalization. However, despite the ubiquity of its use, it is argued that this model is inappropriate. Specific strategies are examined. Attempts to appropriate the title of profession by demonstrating that nursing possesses the relevant attributes are dismissed as rhetorical exercises. The rise of managerialism, despite being cloaked in the guise of professionalism, is seen as anti-professional because it restricts the autonomy of individual practitioners. Clinical 'professionalization' is also regarded as problematic because it does not fit with the definition of a professional as an autonomous practitioner. Examination of patient advocacy, and of attempts to validate nursing diagnosis, demonstrate that the occupational advancement of clinical nurses is increasingly dependent upon the co-operation of health care consumers. This dependence is incompatible with the prescriptive powers and exclusive knowledge that are claimed by traditional professions. It is concluded that nurses should abandon the ideology of professionalization and concentrate on the more pertinent issue of maximizing the efficacy of the occupation.

Purification, Characterization, and Cloning of Cinnamyl Alcohol Dehydrogenase in Loblolly Pine (Pinus taeda L.)

Cinnamyl alcohol dehydrogenase (CAD, EC 1.1.1. 195) has been purified to homogeneity from differentiating xylem tissue and developing seeds of loblolly pine (Pinus taeda L.). The enzyme is a dimer with a native molecular weight of 82,000 and a subunit molecular weight of 44,000, and is the only form of CAD involved in lignification in differentiating xylem. High levels of loblolly pine CAD enzyme were found in nonlignifying seed tissue. Characterization of the enzyme from both seeds and xylem demonstrated that the enzyme is the same in both tissues. The enzyme has a high affinity for coniferaldehyde (K(m) = 1.7 micromolar) compared with sinapaldehyde (K(m) in excess of 100 micromolar). Kinetic data strongly suggest that coniferin is a noncompetitive inhibitor of CAD enzyme activity. Protein sequences were obtained for the N-terminus (28 amino acids) and for two other peptides. Degenerate oligonucleotide primers based on the protein sequences were used to amplify by polymerase chain reaction a 1050 base pair DNA fragment from xylem cDNA. Nucleotide sequence from the cloned DNA fragment coded for the N-terminal protein sequence and an internal peptide of CAD. The N-terminal protein sequence has little similarity with the lambdaCAD4 clone isolated from bean (MH Walter, J Grima-Pettenati, C Grand, AM Boudet, CJ Lamb [1988] Proc Natl Acad Sci USA 86:5546-5550), which has homology with malic enzyme.

Sodium monochloroacetate poisoning of greenfinches

A large number of passerine birds, mainly greenfinches, were found dead or dying in a hedgerow close to a field of onions recently sprayed with sodium monochloroacetate (SMCA). An analytical method is described for isolating monochloroacetic acid from bird tissues, as its potassium salt, by ion exchange chromatography. The ion exchange eluate is evaporated to dryness, acidified, extracted with ether and the ethereal extract methylated with diazomethane. The concentration of the methyl ester of monochloroacetic acid is determined using the Mass Selective Detector in the selected ion mode. Chemical analysis confirmed the exposure of the birds to SMCA. It is calculated that 50 microliter of spray contained the lethal dose of SMCA for a greenfinch.

Working conditions of British resident hospital oral and maxillofacial surgeons

The aim of this study was to determine the opinions of on-call senior house officers in British oral and maxillo-facial surgery, or related units, about aspects of their working conditions. Despite concern about the conditions of service of junior hospital staff in other clinical specialties, the results suggest that most senior house officers in this discipline are satisfied with their present posts. However, regular review of their conditions of service is still indicated.

A cell culture model of the blood-brain barrier

Endothelial cells that make up brain capillaries and constitute the blood-brain barrier become different from peripheral endothelial cells in response to inductive factors found in the nervous system. We have established a cell culture model of the blood-brain barrier by treating brain endothelial cells with a combination of astrocyte-conditioned medium and agents that elevate intracellular cAMP. These cells form high resistance tight junctions and exhibit low rates of paracellular leakage and fluid-phase endocytosis. They also undergo a dramatic structural reorganization as they form tight junctions. Results from these studies suggest modes of manipulating the permeability of the blood-brain barrier, potentially providing the basis for increasing the penetration of drugs into the central nervous system.

The physician as organizational leader

The physician manager is becoming more common. Given the need to bridge the gap between the business and the practice of medicine and given the transformations taking place in health care, physicians will likely play an increasingly important role as leaders in clinics, hospitals, HMOs, and other health care organizations. As yet, a job description for a "leader" remains elusive. However, understanding the framework described here may help build the proper foundation for successful physician leaders.

Viruses and chronic disorders involving the human oral mucosa

Viruses have been implicated in the etiology of several chronic disorders of the oral mucosa. Most of these associations have been with DNA viruses, particularly certain herpesviruses, which are associated, for example, with some cases of erythema multiforme and with hairy leukoplakia. Papillomaviruses are associated with various papillomatous lesions, focal epithelial hyperplasia, and possibly with some carcinomas. Viruses may possibly be associated with recurrent aphthae, Behçet's syndrome, and some dermatoses. The literature concerning these possible associations is reviewed. However, much more research needs to be done before the full story of viral associations with oral mucosal disorders can be written.

A participant observation study of power relations between nurses and doctors in a general hospital

The problem addressed in this paper is how nurse-doctor power relations are manifested in a hospital setting. A review of the literature identified four major ideal types of interaction between nurses and doctors in decision-making processes. These were unproblematic subordination, informal covert decision making, informal overt decision making and formal overt decision making on the part of nurses. Each of these types was tested against empirical data gained from participant observation of interactions between the nurses and doctors working in an intensive care unit and a general medical ward. It was concluded that while both the unproblematic subordination and the informal covert decision-making types of interaction appeared superficially to be used frequently, closer examination revealed that, with the exception of nurse-consultant interactions, nurses were less dependent on these subordinate modes of interaction than much of the literature suggested. Formal overt decision making, despite official encouragement, was also infrequently utilized. However, it was noticed that senior nurses especially used informal overt strategies to involve themselves in decision-making sequences. Use of such strategies had the effect of reducing though not eliminating the power differential between doctors and nurses.

Technology's children: report of a statewide census of children dependent on medical supports

In April 1987, a census of children dependent on medical technology was carried out in Massachusetts to determine the one-month point prevalence. All medical and educational providers in the state who were likely to interact with such children were contacted and asked to complete a two-sided data form on youngsters (aged 3 months to 18 years) with tracheostomies, supplementary oxygen, respirators, suctioning, gastric feeding, central venous lines, ostomies, ureteral diversion, urethral catheterization and dialysis. Nearly 1250 children were found meeting these criteria. Capture-recapture analysis set the lower bound for technology dependence at 0.08% of the state's children. An analysis of the organ systems involved showed that 57% of the children had neurologic involvement--13% multisystem, 7% gastrointestinal-metabolic, 4% renal-genitourinary, and 3% musculoskeletal. Less than 1% of the children were reported as having immunologic or "other" disorders. Review of putative etiologies indicated that 45% of the children had congenital anomalies, 33% chronic medical diseases, 9% perinatal conditions, 7% hereditary-genetic disorders, 5% injuries, 2% infections, and 3% "other." The substantial prevalence of technology dependency among children creates challenges at the social, economic, and policy-making levels. It will be important to carry out systematic reporting and monitoring activities throughout time and across sites. This census is an example of one such statewide effort.

Injuries to dental patients and visitors

Reports were studied of all incidents of injury and accidents involving outpatients or visitors to Bristol Dental Hospital between 1980 and 1988 inclusive. Seventy-two incidents were reported, two-thirds of which occurred during or just after dental treatment, and usually involved oral soft tissues or teeth. Few accidents that occurred at this time could be attributed to faulty equipment. One-third of accidents occurred outside the treatment area, the resultant injuries were usually minor, although one injury was considered serious enough to warrant legal action to be taken against the Health Authority. Hence, it is important that the provisions of the Health and Safety at Work etc. Act (1974) are implemented in all parts of a dental practice to avoid injury to patients.

The level of risk of transmission of human immunodeficiency virus between patients and dental staff

Almost a decade into the epidemic of acquired immunodeficiency syndrome (AIDS) there is adequate evidence to address the concerns of dental staff about possible transmission of human immunodeficiency virus (HIV) between patient and staff. This paper reviews that evidence and demonstrates that the risk of HIV transmission to health care workers is extremely low. Worldwide there are no reported proven cases of occupational transmission of HIV to dental staff.

Multiple alternatively spliced transcripts of the mouse tyrosinase-encoding gene

We have isolated and characterized tyrosinase-specific cDNAs from wild-type mouse skin, to provide a basis for the structural and functional analysis of mutations at the mouse tyrosinase-encoding (Tyr) locus. The cDNAs were synthesized by the polymerase chain reaction. At least twelve alternatively spliced transcripts of the Tyr gene were found, including nine not previously described. Of 51 clones obtained, most (59%) correspond to the full-length cDNA encoding active tyrosinase. The others are shorter and apparently arose by alternative splicing. They are attributable to exon skipping, usage of alternative 5' and/or 3' splice sites, and (in one case) retention of an intronic sequence. Patterns of alternative splicing also occur in other pigmented tissues.

Mosaicism of tyrosinase-locus transcription and chromatin structure in dark vs. light melanocyte clones of homozygous chinchilla-mottled mice

The chinchilla-mottled (cm) mutation at the mouse tyrosinase-encoding locus leads to a transversely striped pattern of dark- and light-grey coat colors in homozygotes. The same basic pattern occurs in various other genotypes and has previously been found to represent the clonal developmental history of melanocytes. In a homozygote such as cm/cm, cis-acting mechanisms would be expected to account for the color differences. To search for these mechanisms, the genomic structure of the mutation was examined and compared with the wild-type, and its function was compared in cultured melanocyte clones of the respective colors. Evidence from restriction mapping indicated that the coding region of the mutant gene resembles that of the fully and uniformly pigmented wild-type. However, the upstream sequences are rearranged in the mutation. The rearrangement begins 5 kb 5' of the transcription initiation site and is estimated to encompass at least 30 kb of distal upstream sequence. At least two stable functional states of the cm gene were detectable: Light-cell clones have low levels of tyrosinase-specific transcription, reduced DNAase I sensitivity of tyrosinase chromatin, and no detectable hypersensitive sites near the gene; dark-cell clones have higher (but subnormal) levels of transcription, greater sensitivity of chromatin to DNAase I, and a hypersensitive site in the promoter region. The changed relation between the structural gene and its upstream region may separate it from cis-acting control elements, resulting in reduced and variable ability to achieve the appropriate chromatin configuration near the time of melanocyte determination; differences in expression among clonal initiator cells are then mitotically perpetuated.