Symptomatic liver hemangioma with intra-tumor hemorrhage treated by angiography and embolization during pregnancy

BACKGROUND

Cavernous hemangiomas are the most common benign tumors of the liver and are found in about 2% of autopsy patients. The vast majority are small (less than 4 cm) and asymptomatic, but there have been a few reported cases of these lesions leading to severe pain and even spontaneous fatal hemorrhage. Estrogen may cause the growth of liver hemangiomas, but there is a paucity of information concerning the effect of pregnancy upon these lesions.

CASE

A patient presented at 18 weeks' gestation with the acute onset of vomiting and epigastric pain. A right upper-quadrant ultrasound scan found a 9-cm hypodense lesion within the liver, and magnetic resonance imaging (MRI) suggested a hemangioma. The lesion was believed to be inoperable, and selective catheterization of the common hepatic artery was performed. An angiogram demonstrated a round vascular mass 12 cm in diameter occupying much of the left side of the liver, with the vascular supply from the middle hepatic artery and to a lesser extent from the left hepatic artery. Embolization was performed, and a post-embolization image demonstrated satisfactory occlusion of the vessels treated. The patient's epigastric pain resolved after the procedure. The lesion was observed with monthly ultrasound and regressed to about 50% of its original size. The patient was scheduled for an elective primary cesarean delivery at 39 weeks to avoid possible rupture of the hepatic hemangioma during the second stage of labor. Her cesarean and postpartum course were uncomplicated.

CONCLUSION

A symptomatic liver hemangioma with intratumor hemorrhage can be successfully treated with embolization during pregnancy. Because of the paucity of reported cases, it is uncertain whether vaginal birth is contraindicated in these patients.

Brain cell membrane Na+,K(+)-ATPase modification following hypoxia in the guinea pig fetus

The effect of hypoxia in utero on the affinity of the active sites of Na+,K(+)-ATPase for Na+, K+ and ATP of the fetal guinea pig brain was investigated. Brain cell membranes were prepared from normoxic and hypoxic guinea pig fetuses, and a detailed enzyme kinetics analysis was carried out. In the hypoxic fetal brain membranes the Ka 0.5 for Na+ and K+ increased 104% and 20+, respectively, indicating a decrease in the affinity of the active sites of the enzyme for Na+ and K+. The affinity of the ATP site increased, as indicated by a decrease in the Km of 37% in hypoxic brain. The results indicate that changes in the affinity of active sites would affect the phosphorylation and dephosphorylation mechanisms of the Na+,K(+)-ATPase reaction. The increased affinity for ATP will favor the phosphorylation step, but will be opposed by the decrease in the Na+ affinity. The decreased affinity of the active site for K+ would oppose the dephosphorylation of the enzyme-P complex causing the enzyme to be trapped in an inactive phosphorylated state. The results demonstrated the sensitivity of the Na+,K(+)-ATPase active sites to hypoxia, and illustrated a selective modification of the enzyme active sites under hypoxic conditions, a key mechanism altering the cell membrane function leading to hypoxic brain damage.

Antibody affinity to retinal S-antigen in patients with retinal vasculitis

Using a modified enzyme-linked immunosorbent antibody method that included dissociation of antigen antibody complexes with sodium thiocyanate, we examined the functional affinity of antibody to retinal S-antigen in 48 patients with retinal vasculitis and 46 age-matched healthy control subjects. Antibody affinity was markedly lower in patients with retinal vasculitis than in healthy subjects. Low-affinity antibody was more prevalent in acute retinal vasculitis and in patients with normal levels of circulating immune complexes. We found distinct differences between the antiretinal antibodies found in patients with retinal vasculitis and those in control subjects. The association of low-affinity antibody with normal levels of circulating immune complexes may suggest defective regulation of antiretinal autoimmunity and have important pathogenic implications.

The Msh-like homeobox genes define domains in the developing vertebrate eye

The mouse Hox-7.1 gene has previously been shown to be related to the Drosophila Msh homeobox-containing gene. Here we report the isolation of a new member of this family which resides at an unlinked chromosomal location and has been designated Hox-8.1. Both Hox-7.1 and Hox-8.1 are expressed in the mouse embryo during the early stages of eye development in a distinct spatial and temporal relationship. Hox-8.1 is expressed in the surface ectoderm and in the optic vesicle before invagination occurs in regions corresponding to the prospective corneal epithelium and neural retina, respectively. Hox-7.1 is expressed after formation of the optic cup, marking the domain that will give rise to the ciliary body. The activity of these genes indicates that the inner layer of the optic cup is differentiated into three distinct compartments before overt cellular differentiation occurs. Our results suggest that these genes are involved in defining the region that gives rise to the inner layer of the optic cup and in patterning this tissue to define the iris, ciliary body and retina.

Molecular size of retinal vascular leakage determined by FITC-dextran angiography in patients with posterior uveitis

In order to investigate the selective breakdown of the blood-retinal barrier in posterior uveitis angiograms were performed using fluorescein-conjugated dextrans (FITC-dextrans) of different molecular weights (150-kDa, 20-kDa, and 4-kDa) in two healthy controls and six patients with posterior uveitis, and the results compared with those of conventional fluorescein angiography. The smallest FITC-dextran could not penetrate the healthy blood-retinal barrier. Leakage of FITC-dextrans of all sizes was seen from swollen optic discs; dextrans of 4-kDa and 20-kDa leaked from areas of macula oedema; and retinal new vessels allowed the passage of 4-kDa molecules only. These results indicate that there is a differential breakdown of the blood-retinal barrier according to molecular size in various clinical situations associated with posterior uveitis.

The challenge facing population geography

The current status of the study of population geography is examined, with some reference to the situation in the United Kingdom. The authors note that whereas the volume of studies in this area indicate its healthy growth, the subdiscipline has become increasingly distant from mainstream geography and runs the risk of being absorbed into general demography. The authors suggest that "population geographers, while taking a serious interest in the methods and philosophy of the neighbouring discipline of demography, should look elsewhere to find direction for their subdiscipline."

Cleaning and disinfection of endoscopes: have there been recent improvements?

OBJECTIVE

to determine if there have been improvements in the manner in which endoscopes are being cleaned and disinfected since our previous study in 1987. In that study of 123 hospitals, in only 45% of institutions did cleaning and disinfection appear to be satisfactory.

DESIGN

One hundred and twenty-two questionnaires were sent to the endoscopy charge nurse of the hospitals identifiable from our previous study. To ensure the collection of complete information from these hospitals, in those from whom a written reply was not received, the information was obtained by persistent telephone contact. The criteria used to assess adequate cleaning and disinfection were the same as in our previous study. These were based on recommendations of learned bodies and the literature.

SETTING

A complete cross section of hospitals from all States and Territories in Australia was surveyed. These were both public and private, primary care to tertiary referral, teaching and non-teaching, city and country.

MAIN OUTCOME

One hundred and twenty-three replies were obtained from the 122 hospitals surveyed. In 75% cleaning and disinfection of endoscopes appeared to be satisfactory. Adequate cleaning procedures were noted in 77% compared with 60% in the 1987 survey. The use of appropriate disinfection increased to 94% from 62% previously.

CONCLUSION

We found that since 1987 there had been a considerable improvement in the cleaning and disinfection of endoscopes in the hospitals surveyed.

Bilateral cilio-retinal artery occlusion in classic migraine

A case of bilateral cilio-retinal artery occlusion in a patient with classic migraine is described. It is unlikely that this hitherto unreported occurrence represents altered tone in the dense adrenergic innervation to the posterior ciliary circulation. We advise the continued use of beta-adrenergic blockers as prophylaxis in ocular migraine.

Health professionals' use of documents obtained through the Regional Medical Library Network

The Pacific Southwest Regional Medical Library Service (PSRMLS) studied how health professionals use documents obtained through the regional medical library (RML) network and how various factors, such as delivery time, affected that use. A random sample of libraries in Region 7 of the RML network was selected to survey health professionals who had received documents through the interlibrary loan (ILL) network. The survey provided data about the purposes for which health professionals requested documents, how the immediacy of need for the items affected their usefulness, what effect the obtained information had on the health professionals' work, and whether the illustrations represented an important part of the information content of the items. Survey results provided a positive assessment of the ILL network. Results also verified the basic value of the materials provided to health professionals through ILL and identified some areas for consideration in future network development. Users of the documents indicated that the network works efficiently and effectively to provide timely and useful information needed by health professionals. Technological developments in electronic information transmission and imaging will further enhance network operation in the future.

Systemic inflammatory disease and the eye

Systemic inflammatory diseases are a spectrum of immunologically mediated disorders that present with multisystem symptoms and signs. Ophthalmological examination often provides important clinical clues to the nature of the underlying disorder and characteristic ocular patterns may be identified that aid diagnosis. This article summarizes the ocular manifestations of systemic inflammatory disease and suggests a rational approach to diagnosis based on the type of ocular vessel predominantly involved in the inflammatory process.

An Australia-wide epidemic of Pseudomonas pickettii bacteraemia due to contaminated "sterile" water for injection

Nineteen cases of Pseudomonas pickettii bacteraemia and one case of Pseudomonas cepacia bacteraemia were identified in an Australia-wide outbreak of nosocomial sepsis associated with contaminated water for injection. The contamination was limited to one batch of commercially produced water for injection. Four different organisms were identified (three biotypes of P. pickettii and one of P. cepacia). However, P. pickettii biotype 1 appeared to be relatively more virulent than the other biotypes as it was the only identified organism in blood cultures in nearly all cases of sepsis. The ampoules of "sterile" water were each contaminated with approximately 10(3) organisms per millilitre. The lack of an Australian central reporting system for bacteraemia delayed the recognition of this outbreak.

Internuclear ophthalmoplegia in giant-cell arteritis

Images

Electroretinography and electro-oculography to localize abnormalities in early-stage inflammatory eye disease

Electrophysiological investigations were performed in patients with inflammatory eye disease characterized by the presence of vitreous cells. The eyes were classified into four categories on the basis of fluorescein angiography: 1) no fluorescein leakage from retinal vessels, 2) fluorescein leakage from peripheral retinal vessels, 3) fluorescein leakage from the disc or macular vessels, and 4) fluorescein leakage from retinal vessels associated with pigment epithelial and choroidal changes. The electro-oculogram light rise was abnormally increased in the eyes in category 1, but it progressively declined for those in the other categories. The ratio of the b-wave (postreceptoral component) and a-wave (receptoral component) of the flash electroretinogram was unchanged in all categories, but the electroretinographic amplitudes progressively declined from a somewhat supernormal level in category 1 to subnormal in the other categories. Thus, in inflammatory eye disease, changes in the electrical potentials arising in the pigment epithelium and photoreceptors are the earliest detectable signs. Some biochemical changes in the choroid, pigment epithelium, and the photoreceptors appear to take place before any pathological changes in these structures or in the retinal vessels are detectable by ophthalmoscopy or fluorescein angiography.

How well are endoscopes cleaned and disinfected between patients?

A questionnaire was sent to 276 hospitals throughout Australia to obtain details on the methods that are used in these institutions for the cleaning and disinfection of endoscopes. A broad range of hospitals was surveyed and 145 responses were received. Endoscopies were performed in 123 of the responding hospitals. Only 45% (55/123) of these hospitals both cleaned and disinfected their endoscopes satisfactorily. Generally, such hospitals were larger (300-600 beds) than were those which did not do so (100-300 beds) and also they were busier as more endoscopies were performed on a weekly basis (30.2 endoscopies compared with 19.3 endoscopies, respectively). Frequently (38% [47/123] of hospitals), the endoscopes were not disinfected between patients, or were disinfected for an insufficient time or were disinfected with an agent that did not have both antiviral and antibacterial activity. In a substantial proportion (40% [49/123]) of hospitals, endoscopes and their accessories appeared to be cleaned inadequately between patients. We conclude that in the majority of hospitals where endoscopies are performed that responded to our survey, there was considerable room for improvement in the cleaning and disinfection of endoscopes.

A new family of mouse homeo box-containing genes: molecular structure, chromosomal location, and developmental expression of Hox-7.1

Two families of homeo box-containing genes have been identified in mammals to date, the Antennapedia- and engrailed-like homeo boxes, based on the sequence similarity to those from Drosophila. Here, we report the isolation of a homeo box-containing gene that belongs to a new family of which there are at least three related genes in the mouse genome. The homeo box of this new gene shows remarkable similarity to the Drosophila Msh homeo box that we designate as the prototype for this family. The gene maps to the proximal end of mouse chromosome 5 and does not cosegregate with any known homeo box-containing gene. We designate this locus Hox-7.1. In situ hybridizations to mouse embryos at different stages show a unique pattern of expression, as compared to other homeo box-containing genes described thus far. Hox-7.1 transcripts are detected in 9.5-day-old embryos in the neural crest, developing limb bud, and visceral arches. Later, this gene is expressed in regions of the face that are derived from neural crest and in the interdigital mesenchymal tissues in both the fore- and hindlimbs.

A gene with sequence similarity to Drosophila engrailed is expressed during the development of the neural tube and vertebrae in the mouse

The mouse genes En-1 and En-2 display sequence similarity, in and around the homeobox region, to the engrailed family in Drosophila. This paper describes their pattern of expression in the 12.5-day mouse embryo as determined by in situ hybridization. En-2 is expressed in a subset of cells expressing En-1. Both genes are expressed in the developing midbrain and its junction with the hindbrain. In addition, En-1 is expressed in the floor of the hindbrain, a restricted ventrolateral segment of the neural tube throughout the trunk and anterior part of the tail, the dermatome of tail somites, the centrum and costal processes in developing vertebrae, a restricted region of facial mesenchyme and the limb-bud ectoderm. Supplementary studies of 9.5-day and 10.5-day embryos showed that the same pattern of expression pertained in the neural tube, but that expression in the somites is at first confined to the dermatome and later found at a low level in restricted sclerotomal regions. Both genes are expressed in restricted domains which do not cross tissue-type boundaries. In several instances, however, boundaries of expression lie within morphologically undifferentiated tissue. These results suggest that En-1 and En-2 may be involved in the establishment or maintenance of the spatial integrity of specific domains within developing tissues.

Neurosarcoidosis

All aspects of neurosarcoidosis are reviewed, including cranial nerve palsies, neurophthalmology, intracranial lesions, meningitis, cerebellar ataxia, peripheral neuritis, hypothalamus, myopathy, neurophysiology, cerebrospinal fluid, differential diagnosis and treatment.

A longitudinal study of clinical and immunological findings in 52 patients with relapsing retinal vasculitis

Fifty-two patients with retinal vasculitis--26 with idiopathic disease and 26 with associated systemic inflammatory disease--were followed up for periods ranging from six months to 12 years. The aim of the study was to determine the relationship between relapse of uveitis, visual outcome, and the occurrence of circulating immune complexes (CIC) and antiretinal antibodies. In a total of 69 relapses, CIC were increased in one-third of patients and antiretinal antibodies in one-half. In those 34 patients who expressed antiretinal antibodies 27 (79%) of the relapses were characterised by antiretinal antibodies in the absence of raised CIC levels (p less than 0.01). These findings support our previous hypothesis that CIC may have a protective role in autoimmune retinal vasculitis and that antiretinal autoimmunity is of pathogenetic importance in relapse. In individual patients the visual outcome was not related to the number of relapses or to the CIC-autoantibody pattern, suggesting the operation of additional features which merit identification.

Compression of the optic chiasm due to a lymphoreticular malignancy

A patient is described who presented with visual loss due to infiltration of the optic chiasm by chronic lymphocytic leukaemia. This case demonstrates intracranial infiltration as a primary presentation of chronic lymphocytic leukaemia without lymphoreticular involvement and, to our knowledge, is the first report of a chiasmal syndrome due to this lymphoproliferative disorder.

Intraocular involvement of T and B cell lymphomas

Six elderly patients with ocular involvement by Non-Hodgkin's lymphoma are reviewed. The characteristic clinical features were a history of fluctuating vision, findings of decreased colour vision, constricted visual fields, vitreous cells and subretinal infiltrates. Fluorescein angiography revealed pigment epithelial abnormalities and attenuated retinal vessels. Non-invasive investigations produced a definite diagnosis in two patients and a presumptive diagnosis in a further three. The ocular involvement was confirmed by vitreous cytology in only one patient: vitreous biopsies in three other patients yielded chronic inflammatory cells and no evidence of lymphoma. The condition responded poorly to steroids but well to radiotherapy.

Determinants of induced sustained arrhythmias in survivors of out-of-hospital ventricular fibrillation

We prospectively studied 196 consecutive survivors of out-of-hospital ventricular fibrillation (VF) not associated with acute myocardial infarction and 46 consecutive, control patients without prior ventricular arrhythmias. Programmed stimulation included two extrastimuli (S3 protocol) in all patients and three extrastimuli (S4 protocol) in the last 140 study patients and in all control patients. Sustained ventricular tachycardia (VT) or VF was not induced in any control patient. In study patients, logistic regression identified two independent predictors of induced, sustained VT for both S3 and S4 protocols: prior spontaneous, sustained VT (37 patients; p less than or equal to .001) and prior myocardial infarction (113 patients; p = .005). With the S3 protocol, sustained VT was induced in 54% of patients with both prior myocardial infarction and prior sustained VT vs 4% without either; with the S4 protocol, sustained VT was induced in 91% vs 13%, respectively. Eighty-three percent of induced VT episodes had a cycle length less than 300 msec, and all required termination by cardioversion or pacing. VF was induced only in survivors of out-of-hospital VF without prior, spontaneous, sustained VT (S3 protocol, 9%; S4 protocol, 24%) but not in study patients with prior sustained VT (S3, p = .10; S4, p = .05) or control patients (S3, p = .06; S4, p = .01). The mean coupling intervals of extrastimuli that induced VF were not significantly different from the intervals that induced sustained VT.(ABSTRACT TRUNCATED AT 250 WORDS)

Impact of the Pacific Southwest Regional Medical Library Service on hospital library development

A study was designed to evaluate the progress of hospital libraries within Region 7 since the Pacific Southwest Regional Medical Library Services (PSRMLS) began in 1969. Library progress was defined as an increase in extent and types of services and resources offered. The study assessed the impact of Regional Medical Library programs on hospital libraries and compared resources and services reported in 1969, 1971, and 1984. The 1984 data were also measured against a set of core library services and resources that should be provided by a full-service hospital library. In addition to assessing the quality of PSRMLS programs and their effect on Region 7 hospital libraries, the study documented extensive growth in staffing, collection size, and services. PSRMLS programs were highly rated by the respondents, who also indicated that participation in PSRMLS programs improved specific library resources and services.

Candida endophthalmitis: a complication of prolonged intravenous therapy and antibiotic treatment

Four patients with candida endophthalmitis are discussed; three had received prolonged intravenous therapy as well as multiple and varied courses of antibiotics for underlying gastro-intestinal disease; one was an intravenous drug abuser. The visual acuity improved dramatically in two of the five affected eyes but in the remaining three eyes remained at 6/60 or less. Visual prognosis is directly related to early diagnosis and treatment, which should include pars plana vitrectomy and systemic antifungal therapy.

Immunology of multisystem ocular disease

In this review based on Prof. James' 1983 George Nelms Wise Lecture, the authors summarize proven and speculated relationships involved in the immunology of multisystem ocular disease. Extensive tables elucidate the mechanisms underlying such conditions as, systemic lupus erythematosus, polyarteritis nodosa, Sjögren's syndrome, Wegener's granulomatosis, scleritis, sarcoidosis, Behcet's disease, idiopathic retinal vasculitis, sympathetic ophthalmia, Vogt-Koyanagi-Harada syndrome, and dysthyroid eye disease.

Salary survey of the Medical Library Group of Southern California and Arizona

The 1982 salary survey of the Medical Library Group of Southern California and Arizona (MLGSCA) indicates that 211 health sciences librarians in Southern California and Arizona earned a mean annual salary of $20,910 for 1982. Data analysis shows a positive correlation between salary and educational level. Other factors found to affect salary were job history, number of positions held, MLA certification, and professional responsibility. Age, gender, and MLA certification did not have a consistent positive correlation with salary. Results indicate that the salaries of hospital librarians are, on the average, roughly comparable to those of academic librarians in Southern California and Arizona.

Correlates of intelligence and adaptive behaviour in Down's syndrome

Intelligence and adaptive behaviour scores of Down's syndrome children were compared with parental educational level, socio-economic indicators, and parental age at birth of the child. IQ and adaptive behaviour scores were positively correlated with parental education and socio-economic indicators. Adaptive behaviour scores of children born to older parents were significantly lower than scores of children born to younger parents.

Anti-retinal autoimmunity and circulating immune complexes in patients with retinal vasculitis

Sera from 44 patients with isolated retinal vasculitis (RV), 38 patients with retinal vasculitis accompanying systemic inflammatory diseases (RV + SID), and 33 patients with a similar range of systemic inflammatory diseases without eye involvement (SID alone) were assayed for circulating immune complexes (CIC) and for anti-retinal autoantibodies. CIC were present in 41% of patients with isolated RV and 55% of patients with RV + SID, whilst anti-retinal antibodies were present in about 70% of all patients with RV. 42% of those with SID alone had CIC and 30% of those with SID alone had retinal autoantibodies. Titres of anti-retinal antibodies were higher in patients with RV than in those with SID alone. In isolated RV there was an inverse relation between pronounced retinal autoimmunity and the occurrence of CIC--i.e., the more severe autoimmune retinal disease occurred in CIC-negative patients. Most patients with RV + SID tended to have mild or moderate retinal disease accompanied by both retinal autoantibodies and CIC, but severe retinal disease occurred in CIC-positive patients who did not have circulating anti-retinal antibodies. Patients with SID alone had high titres of retinal antibodies only when they were CIC-positive. It is suggested that the formation of CIC, possibly of an idiotype/anti-idiotype nature, may be a compensatory mechanism accompanying anti-retinal autoimmunity and that an imbalance between autoimmunity and immune complex formation may be an important predisposing factor in the development of retinal inflammatory disease.

Autoimmunity and circulating immune complexes in retinal vasculitis

This paper presents the results of a point-prevalence study of circulating autoantibodies and immune complexes in 44 patients with isolated retinal vasculitis (RV alone), 38 patients with retinal vasculitis accompanied by systemic inflammatory disease (RV + SID), and 33 patients with a similar range of systemic inflammatory disease but without eye involvement (SID alone). In isolated retinal vasculitis, antiretinal antibodies, non-retinal antibodies, and circulating immune complexes each showed a prevalence of about 50 per cent, but there was an inverse relationship between marked antiretinal autoimmunity and the occurrence of circulating immune complexes. In SID alone, antiretinal antibodies (ret-AB) were of lower prevalence (about 20 per cent) and occurred only in patients who had circulating immune complexes (CIC). Patients with RV + SID fell into two principal categories: (a) ret-AB with CIC, and (b) ret-AB without CIC. In isolated retinal vasculitis, the occurrence of high levels of retinal autoimmunity in the absence of circulating immune complexes was associated with the more severe retinal disease, while in those RV + SID patients who did not express autoimmunity, the more severe retinal disease was associated with the presence of circulating immune complexes. It is suggested that the formation of circulating autoimmune complexes, possibly of an idiotypic: anti-idiotypic character, may be a 'risk' mechanism for limiting retinal-specific autoimmunity, and that certain patients with severe retinal vasculitis may undercompensate or overcompensate in this way.

Prognosis in giant-cell arteritis

In a study to assess the natural history of giant-cell arteritis, 90 patients with proved disease were followed up from the time of diagnosis. Early mortality was low and most commonly due to vertebral arteritis, but cerebral infarction did not appear to be a late complication. High maintenance dose steroids and visual loss were associated significantly with a shortened life span (p=0.0003 and p=0.0024). One-third of the patients developed chronic relapsing disease, but serious late complications were not encountered. After the initial attack has been controlled steroid dosage should be reduced to the minimum needed to alleviate symptoms.

Cavitational bio-effects of 1.5 MHz

The effects of continuous wave ultrasound on three different classes of biosystems have been investigated at a frequency of 1.5 MHz. The criteria for cavitation are given, and these are applied to experimentally observed growth retardation of plant roots, cell death and DNA degradation in bacteria and pyknosis of human lymphocytes. An attempt is being made to find common physical mechanisms for all these biological responses, and cavitation processes in particular are examined here. A description is given of the techniques used to monitor the presence of cavitation, and indirect evidence, drawn from pulsed field and elevated pressure experiments, is presented to show that other-non-linear processes are also operative.

Photosensitization of Escherichia coli and Saccharomyces cerevisiae by phenylheptatriyne from Bidens pilosa

The photosensitizing action of 7-phenylhepta-2,4,6-triyne (PHT), a polyacetylenic compound isolated from Bidens pilosa L. (Asteraceae), has been studied using Escherichia coli and Saccharomyces cerevisiae as the test organisms. The survival curves for E. coli treated with PHT and ultraviolet (UV) radiation were obtained and have been interpreted quantitatively on the basis of a target theory model. The number of "targets" in the cell that must be destroyed before cell death occurs was estimated at six, whereas the dose, D0, that reduced the surviving fraction of the population to 1/e of its value was estimated to be 280 J/m2.Survival was enhanced in aerobic conditions as compared with anaerobic conditions, which is strong evidence that PHT does not behave as a photodynamic sensitizer in vivo. This view was confirmed by work with azide (a quencher of singlet oxygen), D2O (which increases the lifetime of singlet oxygen), and superoxide dismutase (which scavenges superoxide radicals). None of these treatments modified the survival curves significantly, indicating that activated species of O2 are probably not involved in photosensitizations with PHT in vivo.Cell respiration was found to be rapidly inhibited by mild treatments of PHT and UV radiation, suggesting that nuclear metabolism is not the primary target of photosensitization as is the case with another group of photosensitizers, the furanocoumarins. The available evidence indicates that PHT is a representative of a new class of phototoxic compounds. A mechanism of action involving production of free radicals is proposed.

Survival in temporal arteritis

Ninety patients with biopsy proven temporal arteritis have been followed up from 6 months to 12 years. There appear to be two groups of patients who suffer with the disease: those that respond well to treatment and those who follow a chronic course depsite treatment. Serious late complications were not encountered in this series. A high maintenance level of corticosteroids (greater than 10 mg daily) correlates significantly with an increased mortality rate.

Uveitis. A series of 368 patients

During the first 10 years (1963-74) of a new Medical Ophthalmology Unit, 368 of 3,930 admissions had endogenous uveitis, anterior in 215 (58 per cent.), posterior in 65 (18 per cent.), and generalized in 88 (24 per cent.). Acute uveitis in 153 patients tended to have a short course counted in months, whereas in 215 with chronic uveitis the condition was measured over years, punctuated by relapses. Sex distribution was equal. At the time of initial presentation, 60 per cent. of patients were aged 20 to 40 years, 8 per cent. were under 20, and 10 per cent. were over 60 years of age.

The pediatric internship as a teaching technique: a comparison of learning experiences in five hospitals

Five interns joined in a collaborative study to assess their learning experiences during the internship year. A 3 times 5-inch data form was completed for each patient for whom the intern was responsible. Information was gathered on demongraphic characteristics of the patient, the teaching that involved this patient, and what skills were acquired. Nearly 30% of the patients were under 1 year of age; 55% were boys. More than one half of the contacts were in an outpatient or emergency department. Over 80% of the patients had not been seen before; continuity patients made up less than 9% of the contacts. Well-child care was the largest care category (19%), followed by respiratory problems (15%) and injuries (9%). About 40% of the contacts involved a teaching input, mainly from residents, attending physicians, and faculty. Care skills most frequently acquired were physical examination (49%), reading (15%), and interviewing (11%). Cross-tabulations showed that most learning was reported for inpatients, for patients with rare diseases, and when some teaching was involved.