Thermal burns of the spectacle associated with supplementary heating in native New Zealand geckos.

Case history: Gradual onset of ocular opacity was observed in three gold-striped geckos (Woodworthia chrysosiretica), and five Pacific geckos (Dactylocnemis pacificus) held in two adjacent terrariums in a zoological institution located in the North Island of New Zealand. Ultraviolet light and heat had been provided for the previous 3-4 years by a fluorescent bulb, but in the last 4 weeks of winter a ceramic heat bulb had been added, situated 10 cm above the upper mesh of the cageClinical findings: All eight geckos presented with mostly bilateral lesions of varying severity confined to the central or upper quadrant of the spectacles. These lesions ranged from variable areas of opacity within the stroma of the spectacle to similarly distributed ulcers of the surface epithelium of both spectacles. The spectacle lesions in the Pacific geckos responded well to treatment with topical combined antimicrobial therapy, within 18-29 days. The gold-striped geckos suffered complications including dysecdysis, severe spectacle ulceration and perforation, mycotic spectaculitis, and widespread mycotic dermatitis resulting in death or leading to euthanasia.Pathological findings: In the three gold-striped geckos, there were extensive areas of deep ulceration and replacement of the spectacle with a thick serocellular crust containing large numbers of fungal elements. The affected areas of the stroma were expanded by large deposits of proteinaceous and mucinous material, pyknotic cellular debris and moderate numbers of heterophils and macrophages as well as infiltrating fungal hyphae.Diagnosis: Mycotic spectaculitis with ulceration and perforation, and disseminated mycotic dermatitis likely secondary to thermal burns.Clinical relevance: This is the first report of thermal burns of the spectacle in any reptile. There was species variation in the burn severity with gold-striped geckos showing more severe lesions, possibly due to a mix of behavioural and anatomical factors. The thermal burns to the spectacles in three cases were complicated by delayed healing, perforation, dysecdysis and severe mycotic infection.

Melanocyte culture lines from Tyr-SV40E transgenic mice: models for the molecular genetic evolution of malignant melanoma.

Transgenic Tyr-SV40E mice previously produced on the C57BL/6 inbred-strain background, with SV40 oncogenic sequences specifically expressed in pigment cells, are predisposed to melanoma [Bradl, M., Klein-Szanto, A., Porter, S. & Mintz, B. (1991). Proc. Natl. Acad. Sci. USA, 88, 164-168]. Separate lines of these animals differ genetically only in the number of copies and chromosomal site of integration of the transgene. Skin melanocytes from young mice with no apparent skin lesions were established in continuous culture from hemizygous donors with low, medium and high numbers of transgene copies, and from a homozygous offspring of the low-copy mouse line. The standard culture conditions enable C57BL/6 wild-type melanocytes to become stably immortalized without transformation. The transgenic cell lines all changed over time in an orderly progression. However, with greater numbers of transgene copies, the cells more rapidly displayed shorter doubling times, increased anchorage independence, reduced serum and growth factor requirements, decreased tyrosinase expression and melanin content, increased oncogene expression, and capacity to form malignant melanomas when tested by grafting. Melanocytes with the lowest number of transgene copies were of special interest. They grew more rapidly than the wild-type cells from the outset, but did not become tumorigenic until an apparently small number of still-unknown genetic changes had spontaneously occurred, or until the number of transgene copies was increased slightly by homozygosity. In contrast to the hemizygous low-copy cells, the homozygous counterparts underwent striking and rapid transformational changes and early conversion to malignancy. Thus such low-copy transgenic melanocyte lines afford an exceptional opportunity for molecular analysis of somatic genetic evolution toward malignant melanoma.

The independent role of cytomegalovirus as a risk factor for invasive fungal disease in orthotopic liver transplant recipients. Boston Center for Liver Transplantation CMVIG-Study Group. Cytogam, MedImmune, Inc. Gaithersburg, Maryland.

PURPOSE: To assess impact of cytomegalovirus (CMV) donor-recipient serostatus, infection, or disease on development of invasive fungal infection in orthotopic liver transplant recipients. PATIENTS AND METHODS: An analysis of prospectively collected data in 146 liver transplant recipients (intention to treat cohort) from 4 tertiary care, university-affiliated transplant centers in Boston (Boston Center for Liver Transplantation). Patients were observed for 1 year after transplantation for the development of CMV infection, CMV disease, CMV pneumonia, as well as for the development of opportunistic fungal infections, graft survival, and mortality. Weekly cultures were taken of urine and throat and every other week of buffy coat for CMV for 2 months, then monthly for 6 months, at 1 year, and at the time of any clinical illness. Pre- and posttransplant variables including CMV-serostatus of donor and recipient, fungal isolation from sterile body sites, fungemia, bacteremia, antibiotic use, immunosuppression, treatment for rejection, and volumes of blood products were measured. RESULTS: Survival analysis demonstrated that 36% of patients with CMV disease developed invasive fungal disease within the first year post-transplant compared with 8% of those without CMV disease (P < 0.0001). One-year mortality in patients with invasive fungal disease was 15 of 22 (68%) compared with 23 of 124 (19%) in those without invasive fungal disease (P < 0.001). A multivariable, time-dependent analysis demonstrated that being a CMV-seronegative recipient of a CMV-seropositive donor organ (P < 0.001), having bacteremia (P = 0.001), UNOS (United Network for Organ Sharing) status 4 (need for life support measures) at transplant (P = 0.002), and volume of platelets (P = 0.002) were independently associated with invasive fungal disease. Restriction of cases of invasive fungal disease to those that occurred more than 2 weeks after transplant demonstrated an association with CMV disease (P = 0.003), bacteremia (P = 0.003), need for life support (P = 0.03), and volume of blood products transfused (P = 0.02). CONCLUSION: CMV disease or being a CMV-seronegative recipient of a CMV-seropositive donor organ is an important predictor for invasive fungal disease following orthotopic liver transplantation.

Respiratory syncytial virus immunoprophylaxis: impact on epidemiology.

OBJECTIVE: To better understand the spectrum of disease among hospitalised children infected with respiratory syncytial virus (RSV) and to assess the potential impact of passive immunoprophylaxis on RSV hospitalisation rates, we analysed all patients infected with RSV who were admitted to a paediatric teaching hospital over a 3-year period. DESIGN: We performed a retrospective chart review of all paediatric patients from whom RSV was isolated between October 1, 1994 and April 30, 1997. RESULTS: A total of 255 children infected with RSV were hospitalised during this 3-year period. 246 (96%) patients had community acquired infections and 9 (4%) had nosocomial infections. Excluding patients with nosocomial infections, the mean length of hospital stay was 4.7 days. 70 (28%) children were admitted to the intensive care unit, 32 (13%) were intubated and there was a total of 4 deaths (1.6%). 48% of hospitalised patients were in 1 of 4 previously recognised high risk groups. Of the 52% of patients not in a defined high risk category, 42% were otherwise healthy infants (>6 weeks of age) and 10% had chronic underlying illnesses generally not associated with an increased risk of severe RSV disease. Patients not in a defined high risk category accounted for 46% of total hospital days. CONCLUSION: In order to reduce overall RSV hospitalisation rates and the economic burden to society, programmes for disease prevention must be directed at healthy infants as well as children in recognised high risk categories. Even if all currently eligible candidates were to have received passive immunoprophylaxis, which yields about a 50% reduction in hospitalisation rates, the number of RSV hospitalisations in our 3-year study would have been reduced by no more than 9%. Without development and widespread use of an effective RSV vaccine, a major impact on RSV-induced hospitalisation is unlikely.

Alternative therapies in the treatment or oral self-injurious behavior: a case report.

This paper presents the case of a child with severe mental retardation and a history of oral self-injurious behavior (SIB). While the behavior was refractory to a number of dental interventions, some success was achieved through a combination of behavioral therapy techniques and therapeutic touch (a relaxation technique). Etiologies of SIB are discussed, along with descriptions of alternatives to traditional dental therapy for this difficult problem.

Genetic predisposition of transgenic mouse melanocytes to melanoma results in malignant melanoma after exposure to a low ultraviolet B intensity nontumorigenic for normal melanocytes.

Tyr-SV40E transgenic mice are susceptible to melanoma due to simian virus 40 oncogenic sequences specifically expressed in pigment cells. Skin melanomas form relatively late. Therefore, melanocyte cell lines have been established from very young transgenic animals, when they showed no skin lesions, so that the spontaneous and gradual progress of the cells toward tumorigenesis could be characterized under culture conditions in which wild-type cells of the same inbred strain remain untransformed. Melanocytes of an in vitro transgenic line were irradiated with very low intensities of ultraviolet B (UVB) (280- to 320-nm wavelength) light at culture passages when the cells had not achieved anchorage independence. After a single exposure to 0.7 mJ/cm2 of UVB radiation, the cells became anchorage independent and formed foci at confluence; however, cells propagated from the foci were not tumorigenic. After one exposure to 1.75 mJ/cm2, more numerous and larger foci resulted, and the cells grown from them yielded malignant melanomas in graft hosts. Wild-type melanocytes were not transformed at these UVB doses. At least two genetic changes contributing to malignant conversion--in addition to the initiating effect of the transgene--are likely to have occurred, one change leading to anchorage independence and another to further progress toward malignancy. Cells at these stages provide an opportunity to isolate the relevant genes and identify any molecular defects attributable to UVB. Tumorigenesis after a very low UVB dose in cells where an initiating stimulus is already present suggests that some other stimulus, such as a gene or a carcinogen, might lead to melanoma in conjunction with exposure to relatively little UVB.

Histamine stimulates calcium-mediated protein phosphorylation in a colonic epithelial cell line.

Protein phosphorylation responses in intact enterocytes were examined by stimulating 32Pi-labeled T84 cell monolayers with histamine and resolving proteins by two-dimensional gel electrophoresis. Histamine increases 32P-incorporation into two acidic proteins of Mr 83,000 and of Mr 29,000, designated p83 and p29. Labeling of p83 and p29 is also increased in cells exposed to ionomycin, but not in cells exposed to vasoactive intestinal peptide under conditions resulting in cAMP-mediated secretion and cAMP-stimulated protein phosphorylation. When T84 cell fractions are incubated with [gamma-32P]ATP, labeling of p83 is stimulated by Ca++, but not by cAMP. Thus, histamine stimulates Ca++-mediated protein phosphorylation during the regulation of Cl- secretion.

Purification and characterization of a phosphatidylinositol kinase from A431 cells.

A phosphatidylinositol kinase from A431 cells has been purified to near homogeneity. Purification was achieved through the use of a combination of chromatography steps including affinity elution of the enzyme from a heparin-agarose column with PI. Characterization of the [32P]PIP formed by the purified PI kinase indicates that the enzyme phosphorylates the inositol on the 4-position and is therefore a phosphatidylinositol 4-kinase. The enzyme has a subunit weight of 55,000 as estimated by SDS gel electrophoresis and appears to be active as a monomer. Studies of the hydrodynamic properties of the enzyme indicate that the PI kinase binds substantial amounts of Triton X-100 and is actually present in detergent-containing solutions as a complex with a molecular weight of approximately 120,000. The Km of the enzyme for PI is 16 microM and for ATP is 74 microM. The enzyme is inhibited by adenosine with an IC50 of 100 microM. These properties are essentially identical with those of the membrane-bound PI kinase in A431 cells which is stimulated by EGF. The data therefore suggest that the EGF-stimulated PI kinase is a 55,000-Da monomer.

IAIMS and the library at the University of Utah.

The formal creation of an Integrated Academic Information Management System (IAIMS) at the University of Utah began in the fall of 1983. The keystone of the IAIMS effort is the HELP hospital information system. IAIMS at the University of Utah is a broad-based program extending across the Health Sciences Center and beyond to health professionals throughout the inter-mountain area. This paper describes the background that led to IAIMS, the IAIMS planning process, and the library's participation in this effort.

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.

Trends in special care training in pediatric dental residencies.

Pediatric dentist are often regarded by the dental community as the specialty group best prepared to treat patients with developmental disabilities. This may be because it is the only specialty that receives formal training in behavior management techniques. A questionnaire was mailed to the directors of all 55 ADA-accredited pediatric dental residency programs in the U.S. The purpose of the survey was two-fold: the first aim was to quantify the training that pediatric dental residents receive in providing care to persons with developmental disabilities. A second area of investigation addressed the issue of pediatric dentist continuing yo treat persons with developmental disabilities into adulthood. The survey determined that pediatric dental residency programs provide considerable training in "Special Care" dentistry. While adults with developmental disabilities continue to be treated in 48 percent of responding programs, 55 percent of the program directors stated outright that it should not be the role of pediatric dentist to provide treatment to this population.

Predoctoral education in special care dentistry: paving the way to better access?

The number of people with mental retardation and developmental disabilities (MR/DD) living in small community-based group residences is increasing throughout the United States. Dental services to this population, once provided in large institutional settings, must increasingly be sought at the community level. The purpose of this study was to determine whether U.S. and Canadian dental schools are adequately training their students to provide quality dental care to this group with complex psychosocial and medical issues. With a response rate of 78 percent to a mail survey, it was found that 53 percent of the schools provide less than five hours of didactic training in special care dentistry. Clinical training in this area comprised only 0-5 percent of predoctoral students' time in 73 percent of the responding schools.

Fine-scale transgenic mapping of the MyoD core enhancer: MyoD is regulated by distinct but overlapping mechanisms in myotomal and non-myotomal muscle lineages.

Skeletal muscle lineage determination is regulated by the myogenic regulatory genes, MyoD and Myf-5. Previously, we identified a 258 bp core enhancer element 20 kb 5' of the MyoD gene that regulates MyoD gene activation in mouse embryos. To elucidate the cis control mechanisms that regulate MyoD transcription, we have mutagenized the entire core enhancer using linker-scanner mutagenesis, and have tested the transcriptional activity of enhancer mutants using lacZ reporter gene expression in transgenic mouse embryos. In total, 83 stable transgenic lines representing 17 linker-scanner mutations were analyzed in midgestational mouse embryos. Eight linker-scanner mutations resulted in a partial or complete loss of enhancer activity, demonstrating that MyoD is primarily under positive transcriptional control. Six of these mutations reduced or abolished transgene expression in all skeletal muscle lineages, indicating that activation of MyoD expression in trunk, limb and head musculature is regulated, in part, by shared transcriptional mechanisms. Interestingly, however, two adjacent linker-scanner mutations (LS-14 and LS-15) resulted in a dramatic reduction in transgene expression specifically in myotomes at 11.5 days. At later stages, transgene expression was absent or greatly reduced in myotomally derived muscles including epaxial muscles (deep back muscles) and hypaxial muscles of the body wall (intercostal muscles, abdominal wall musculature). In contrast, head muscles, as well as muscles of the body derived from migrating muscle progenitor cells (e.g. limb, diaphragm), were unaffected by these mutations. In Pax-3-mutant mice, LS-14 and LS-15 transgene expression was eliminated in the body, but was unaffected in the head, yielding an identical expression pattern to the endogenous MyoD gene in mice mutant for both Myf-5 and Pax-3. These data support the hypothesis that LS-14 and LS-15 define the core enhancer targets for Myf-5-dependent activation of MyoD in myotomal muscles.

Cytomegalovirus immune globulin prophylaxis in liver transplantation. A randomized, double-blind, placebo-controlled trial.

OBJECTIVE: To study the effect of cytomegalovirus immune globulin (CMVIG) on prevention of cytomegalovirus (CMV) disease and its complications in patients receiving liver transplants. DESIGN: Randomized, multicenter, placebo-controlled, double-blind trial. SETTING: Four university-affiliated transplant centers in Boston (Boston Center for Liver Transplantation). PATIENTS: One hundred forty-one liver transplant recipients completed the study. INTERVENTION: CMVIG or placebo (1% albumin) given in a dose of 150 mg/kg body weight within 72 hours of the transplant, then at weeks 2, 4, 6, and 8, and at 100 mg/kg at weeks 12 and 16. MEASUREMENTS: Patients were observed for 1 year after transplantation for the development of CMV infection, disease, pneumonia, as well as for opportunistic fungal infections, graft survival, and mortality. Weekly cultures were taken of urine, buffy coat, and throat wash for CMV for 2 months, then monthly, and at any clinical illness. RESULTS: Using a Cox proportional hazards model, CMVIG was shown to reduce severe CMV-associated disease (multi-organ CMV disease, CMV pneumonia, or invasive fungal disease associated with CMV infection) from 26% to 12% (relative risk, 0.39; 95% CI, 0.17 to 0.89). When we controlled for the use of monoclonal antibodies to T cells (OKT3), CMVIG use was still protective (relative risk, 0.39; CI, 0.17 to 0.90). Rates of CMV disease were reduced from 31% to 19% (relative risk, 0.56; CI, 0.3 to 1.1) in CMVIG recipients although no effect on rates of CMV infection, graft survival, or patient survival at 1 year were shown. When we controlled for the urgency of transplantation and OKT3 use, a reduction in CMV disease (relative risk, 0.22; CI, 0.06 to 0.81) was shown for globulin recipients for all serologic groups except for the highest risk group (the CMV-seropositive donor, CMV-seronegative group). CONCLUSION: CMVIG reduced the rate of severe CMV-associated disease in patients undergoing orthotopic liver transplantation. No effect of CMVIG on CMV donor-positive, recipient-negative liver transplant recipients was shown, suggesting a need for additional prophylactic strategies.