Identification of the Bacterial Leaf Spot Pathogen of Lettuce, Xanthomonas campestris pv. vitians, in Ohio, and Assessment of Cultivar Resistance and Seed Treatment

In 1995, a bacterial leaf spot disease was observed on lettuce plants grown on muck soils in north central Ohio. Characteristic symptoms were water-soaked circular, dark brown- or olivecolored spots, approximately 1 to 2 mm in diameter, along the margin of leaves; V-shaped lesions beginning at the leaf margins and advancing along the veins; and individual black spots scattered on the leaf surface. Five bacterial strains were isolated from infected leaves of two lettuce cultivars, Darkland and Go Go Green. These strains were identified as Xanthomonas campestris pv. vitians based on morphological, physiological, biochemical, and pathogenicity tests, as well as fatty acid methyl ester (FAME) analyses. One of the five strains tested was resistant to streptomycin sulfate (100 μg/ml), and none were resistant to copper sulfate. Eight commercial lettuce cultivars were evaluated for resistance to X. campestris pv. vitians. Of these cultivars, Redine was highly resistant; Focus and Crisp and Green were partially resistant; Slobolt, Tiara, and Carmona were susceptible; and Darkland and Go Go Green were highly susceptible to the pathogen. Surface disinfection with 0.52% sodium hypochlorite for 5 min nearly eliminated the bacterium from lettuce seed without affecting seed viability.

A New Pathotype of Xanthomonas campestris pv. armoraciae That Causes Bacterial Leaf Spot of Radish

A previously undescribed pathotype of Xanthomonas campestris pv. armoraciae was found in 1995 on radish plants grown on organic soil in north central Ohio. Radish foliage developed numerous small, circular, water-soaked black spots, eventually with yellow halos, on the underside of the leaves, giving the foliage a yellowish, ragged appearance. Spots were also visible on the upper surface of leaves and on petioles. Yellow xanthomonad-like bacteria were consistently isolated from the lesions and confirmed as the causal agent of the disease by fulfilling Koch's postulates. All five strains purified were gram negative, rod shaped, motile, aerobic, oxidase negative, catalase positive, amylolytic, and pectolytic. They were identified as X. campestris pv. armoraciae by fatty acid methyl ester (FAME) analysis (similarity indices [SI] range = 0.21 to 0.39), the Biolog 95 GN reaction (SI range = 0.31 to 0.36), and serological reactions with X. campestris pv. campestris/X. campestris pv. armoraciae-specific monoclonal antibodies X9, X11, X21, A11, and B35 (1). All strains caused bacterial leaf spot on collard, kale, radish, horseradish, and cabbage but not on tomato or pepper. These strains were different from X. campestris pv. raphani, which is pathogenic on kale, radish, cabbage, tomato, and pepper, but not on horseradish. These strains also differed from other previously reported strains of X. campestris pv. armoraciae that do not cause infection on kale and radish (1,2). This is the first report on the existence of a different pathogenic group within X. campestris pv. armoraciae that can cause bacterial spot on kale and radish. References: (1) A. M. Alvarez et al. Phytopathology 84:1449, 1994; (2) H. E. White. Phytopathology 20:653, 1930.

Analysis of hospital charges after simultaneous pancreas-kidney transplantation in the era of managed care

BACKGROUND

The purpose of this study was to analyze and compare hospital charges in simultaneous pancreas-kidney transplant (SPKT) recipients before and after implementation of managed care principles.

METHODS

Two groups were compared: 14 consecutive SPKT patients transplanted in 1991 vs. 15 consecutive SPKT patients transplanted in 1995. All patients underwent whole organ pancreas transplantation with bladder drainage and received quadruple immunosuppression with OKT3 induction. The two groups were well-matched; outliers were excluded (four in 1991 and five in 1995), and no attempt was made to convert 1991 to 1995 dollars. Patient and graft survival rates were 100%, and no major early complications occurred. All SPKTs were performed in a single hospital setting, and all inpatient charges for the initial hospitalization were analyzed retrospectively and itemized by service.

RESULTS

Pharmacy, organ acquisition, and clinical laboratory services accounted for nearly 80% of charges in each group. For the initial transplant hospitalization, the 1995 group experienced significant reductions in: (1) length of stay (16.3+/-1.4-135+/-3.5 days, P=0.03); (2) total number of laboratory tests (392+/-15-224+/-60, P<10(-3)); (3) clinical laboratory charges ($23,623+/-$1,780-$11,165+/-$3,091, P<10(-6)); and (4) total inpatient charges with organ acquisition charges excluded ($87,815+/-$8,678-$75,152+/-$16,871, P=0.049). However, these potential savings were offset by a nearly 47% increase in organ acquisition charges and a 38% increase in medical/surgical supplies. Consequently, total hospital charges for SPKT were no different in 1991 and 1995.

CONCLUSIONS

Despite the rising costs of medical care, we have implemented managed care principles after SPKT that were successful in stabilizing hospital charges by decreasing length of stay and clinical laboratory tests during the study period. However, escalating charges related to organ acquisition and medical/surgical supplies remain a problem.

Long-term survivors of pediatric heart transplantation: a multicenter report of sixty-eight children who have survived longer than five years

OBJECTIVE

Short-term survival after pediatric heart transplantation is now excellent, but ultimately the efficacy of this procedure will depend on duration and quality of survival. We sought to evaluate the clinical course of long-term survivors of heart transplantation in childhood.

METHODS

Patients who had undergone heart transplantation at the university hospitals of Stanford, Columbia, and Pittsburgh between 1975 and 1989 and survived longer than 5 years from transplantation were identified and their clinical courses retrospectively reviewed.

RESULTS

Sixty eight children have survived more than 5 years from transplantation, and 60 (88%) are currently alive with a median follow-up of 6.8 years (5 to 17.9 years). Thirteen have survived more than 10 years from transplantation. Renal dysfunction caused by immunosuppressive agents was common, and two patients required late renal transplantation. Lymphoproliferative disease or other neoplasm occurred in 12 patients, but none resulted in death. Coronary artery disease was diagnosed in 13 patients (19%), leading to retransplantation in eight. Death after 5 years was related to acute or chronic rejection in 5 of 8 cases. Two of the deaths were directly related to noncompliance with immunosuppressive medication. All survivors are in New York Heart Association class 1.

CONCLUSIONS

Long-term survival with good quality of life can be achieved after heart transplantation in childhood, though complications of immunosuppression remain common. Posttransplantation coronary artery disease is emerging as the main factor limiting long term graft and patient survival.

Young children's understanding of conflicting mental representation predicts suggestibility

This study examined the relation between developmental suggestibility effects and preschoolers' emerging ability to reason about conflicting mental representations (CMRs). Three- to 5-year-olds listened to a story accompanied by pictures. Following a 4-min delay, children answered straightforward and misleading questions about the story. One week later, their memory for the story was assessed. Children also completed tasks indexing their ability to reason about CMRs. Stepwise regression analyses revealed that suggestibility was negatively related to performance on CMR tasks. This finding remained significant after controlling for age, children's level of initial encoding of the event, and their ability to retrieve event details when not misled. An integration is proposed between children's theory of mind and source monitoring that may help to explain early developmental changes in suggestibility.

New-onset diabetes mellitus in pediatric thoracic organ recipients receiving tacrolimus-based immunosuppression

BACKGROUND

Tacrolimus has a negative effect on the pancreatic beta islet cell, and both glucose intolerance and diabetes mellitus are well-recognized complications of tacrolimus-based immunosuppression among adult solid organ transplant recipients.

METHODS

To determine the association between tacrolimus and new-onset diabetes mellitus in childhood, we reviewed data on 78 pediatric heart and heart-lung/lung recipients receiving tacrolimus-based immunosuppression. Trough tacrolimus levels, fasting and random blood glucose levels, and corticosteroid requirements were reviewed. Diabetes was defined as glucose intolerance requiring long-term insulin treatment more than 30 days after transplantation.

RESULTS

No patient had diabetes before introduction of tacrolimus. In heart-lung/lung recipients, 12 of 28 (43%) had development of diabetes at a median follow-up of 7 months (range 1 to 39). In this group diabetes developed in three of eight (38%) patients with cystic fibrosis and nine of 20 (45%) without (p = NS). In contrast, only two of 50 (4%) heart transplant recipients had development of diabetes. Of the 14 patients with diabetes, 10 had development of diabetes during augmentation of immunosuppression with pulsed corticosteroids. Tacrolimus trough levels were significantly lower in heart compared with heart-lung/lung transplant recipients (9.4 +/- 3.3 versus 15.3 +/- 0.9 ng/ml) (p < 0.01), and at latest follow-up significantly fewer heart transplant recipients were treated with maintenance corticosteroids (28% versus 75%; p < 0.01). In the heart-lung/lung group, no significant difference in tacrolimus levels was found between patients with and without diabetes, nor was there a significant difference in the average corticosteroid dose or number of pulses of corticosteroids per patient.

CONCLUSIONS

New-onset diabetes mellitus is rare in pediatric heart transplant recipients receiving tacrolimus-based immunosuppression, but it occurs with a high incidence after pediatric heart-lung/lung transplantation and usually develops during pulsed corticosteroid therapy. However, it is currently not possible to predict which heart-lung/ lung transplant recipients will have development of this serious complication.

Blockade of hippocampal long-term potentiation following soman pretreatment in the rat

One of the most potent toxins known is the cholinesterase inhibitor, soman, which produces severe convulsions and cell loss in the central nervous system. In these experiments the effect of multiple low doses of soman on the acquisition and maintenance of long-term potentiation (LTP) was determined in rats. LTP is a form of synaptic plasticity that has been studied as a cellular substrate for learning and memory mechanisms. Under urethane anesthesia, electrodes were positioned in the dentate gyrus for recording evoked potentials before and after tetanic stimulation of the perforant path. LTP levels were greatly reduced in rats recovering from convulsion-inducing soman treatment. Rats exposed to similar amounts of soman, but not displaying convulsions, also displayed reduced levels of LTP. The responses recorded from these animals were highly variable, ranging from control levels of potentiation to no LTP. The variability could be attributed to some animals having convulsions that were not detected before surgery or to other interanimal differences in the degree of soman-induced toxicity. The long range goal of the experiments presented here is to develop a better rodent model for studying soman-induced functional changes in the CNS that can be detected prior to the gross morphological changes.

Distribution of Phytophthora spp. in Field Soils Determined by Immunoassay

ABSTRACT Populations of Phytophthora spp. were determined by enzyme-linked immunosorbent assay (ELISA) in field soils used for pepper and soybean production in Ohio. Soybean fields were sampled extensively (64 fields, n = 6 samples per field over 2 years) and intensively (4 fields, n = 64 samples per field in 1 year) to assess heterogeneity of P. sojae populations. Four pepper fields (n = 64), three of which had a history of Phytophthora blight (caused by P. capsici), also were sampled intensively during a 6-month period. Mean (m), variance (v), and measures of aggregation (e.g., variance-to-mean ratio [v/m]) of immunoassay values, translated to Phytophthora antigen units (PAU), were related to the disease history in each of the pepper and soybean fields. Mean PAU values for fields in which Phytophthora root rot (soybean) or blight (pepper) had been moderate to severe were higher than in fields in which disease incidence had been low or not observed. A detection threshold value of 11.3 PAU was calculated with values for 64 samples from one pepper field, all of which tested negative for Phytophthora by bioassay and ELISA. Seven of the eight intensively sampled fields contained at least some detectable Phytophthora propagules, with the percentage of positive samples ranging from 1.6 to 73.4. Mean PAU values ranged from 1 to 84 (extensive soybean field sampling), 6 to 24 (intensive soybean field sampling), and 4 to 30 (intensive pepper field sampling); however, variances ranged from 0 to 7,774 (extensive sampling), 30 to 848 (intensive soybean field sampling), and 5 to 2,401 (intensive pepper field sampling). Heterogeneity of PAU was high in most individual soybean and pepper fields, with values of v/m greater than 1, and log(v) increasing with log(m), with a slope of about 2.0. Spatial autocorrelation coefficients were not significant, indicating there was no relationship of PAU values in neighboring sampling units (i.e., field locations) of the intensively sampled fields. Combined results for autocorrelations and v/m values indicate that Phytophthora was highly aggregated in these fields but that the scale of the aggregation (e.g., average focus size) was less than the size of the sampling units. Because of the observed variability, we calculated that sample sizes of 20 or more would be needed to estimate precisely the mean density of Phytophthora in most cases.

Young children's understanding of conflicting mental representation predicts suggestibility

This study examined the relation between developmental suggestibility effects and preschoolers' emerging ability to reason about conflicting mental representations (CMRs). Three- to 5-year-olds listened to a story accompanied by pictures. Following a 4-min delay, children answered straightforward and misleading questions about the story. One week later, their memory for the story was assessed. Children also completed tasks indexing their ability to reason about CMRs. Stepwise regression analyses revealed that suggestibility was negatively related to performance on CMR tasks. This finding remained significant after controlling for age, children's level of initial encoding of the event, and their ability to retrieve event details when not misled. An integration is proposed between children's theory of mind and source monitoring that may help to explain early developmental changes in suggestibility.

Are chest radiographs and electrocardiograms still valuable in evaluating new pediatric patients with heart murmurs or chest pain?

OBJECTIVES

To determine the usefulness of electrocardiography (ECG) and chest radiography (CXR) in evaluation of patients referred to the pediatric cardiologist for the evaluation of heart murmur or chest pain.

DESIGN

In this prospective study, 106 consecutive outpatients were categorized with no heart disease, possible heart disease, or definite heart disease based on history and physical examination; they then underwent ECG and CXR. Studies were reviewed and the examining cardiologist could change the diagnosis and order an echocardiogram.

SETTING

Academic pediatric cardiology practice.

RESULTS

In patients thought to have no heart disease, the diagnosis was changed to definite heart disease in four solely on the basis of abnormal CXR or ECG. In 25 patients thought to have possible heart disease, the diagnosis was changed to no heart disease (7) or definite heart disease (5) after review of the CXR and ECG. All 25 patients diagnosed with definite heart disease had this confirmed by abnormal CXR (2), ECG (3), both abnormal CXR and ECG, or echocardiogram (18).

CONCLUSIONS

ECG and CXR helped diagnose heart disease in four patients thought to have no heart disease, helped to rule out lesions in seven patients with possible heart disease, helped diagnose heart disease in five patients thought to have possible heart disease, and helped confirm heart disease in nine patients. In these days of cost containment, routine ECG and CXR continue to be valuable tools for the pediatric cardiologist in evaluation of patients with heart murmurs or chest pain.

A Cross-Task Comparison of False Belief Understanding in a Head Start Population

This research had two main goals: to compare different methods of assessing understanding of false belief and to extend the study of false belief to the population served by Project Head Start. Across two experiments the participants were ninety 3-, 4-, and 5-year-old children, drawn from low-income, primarily African-American families. Each child responded to a battery of false belief tasks that varied in the type of belief in question (contents tasks versus locations tasks), the target for the belief ascription (own belief versus other's belief), the method of presenting the reality information (visual versus verbal), and the presence or absence of a deception context. Performance was better on locations tasks than on contents tasks and among older children compared to younger children; the other comparisons resulted in smaller and less consistent effects. Despite the improvement with age, the level of performance fell short of that typically reported in the literature. Although correlations among tasks were significant, fewer than half of the children performed consistently across the problems.

Kinematics of four methods of stabbing: a preliminary study

Despite considerable research and development into stab-resistant clothing, no data exists which provides valid data for knife-body contact speeds which may be used to ensure that an appropriate and standard protection level is provided. Such data can only be obtained by a quantitative kinematic analysis of the stabbing movement. Two-dimensional video techniques (50 Hz) were used to record images of subjects (n = 10) performing each of four stabbing actions; Long Over (LO), Long Under (LU), Short Over (SO), Short Under (SU). Images were digitised from a minimum of ten frames pre-, to at least six frames post-blade entry. A two-way analysis of variance applied to selected kinematic parameters revealed significantly higher (P < 0.01) blade entry speeds for LO and LU as compared to SO and SU, respectively. This was due to the extra distance over which knife speed could be increased in the former conditions. Significantly greater shoulder joint angular velocities were found for LU and SU conditions, whilst for the elbow joint, conditions LO and SO were significantly greater (P = 0.000008). This suggests that the entry speeds during LO and SO are derived from a greater contribution from elbow extensor muscles, whilst those for LU and SU are derived from a greater contribution from the shoulder flexors. It was concluded that two separate kinematic strategies were employed by subjects, and that the maximum speed which may be generated during stabbing is influenced by the manner in which the knife is held.

Medical UV exposures and HIV activation

This paper presents the first attempt to evaluate the potential of clinical UV exposures to induce the human immunodeficiency (HIV) promoter and, thus, to upregulate HIV growth in those skin cells that are directly affected by the exposure. Using the data for HIV promoter activation in vitro, we computed UVB and psoralen plus UVA (PUVA) doses that produce 50% of the maximal promoter activation (AD50). Then, using (a) literature data for UV transmittance in the human skin, (b) a composite action spectrum for HIV promoter and pyrimidine dimer induction by UVB and (c) an action spectrum for DNA synthesis inhibition by PUVA, we estimated the distribution of medical UVB and PUVA doses in the skin. This allowed us to estimate how deep into the skin the HIV-activating doses might penetrate in an initial and an advanced stage of UVB or PUVA therapy. Such analysis was done for normal type II skin and for single exposures. The results allow us to predict where in the skin the HIV promoter may be induced by selected small and large therapeutic UVB or PUVA doses. To accommodate changes in skin topography due to disease and UV therapy, our considerations would require further refinements. For UVB we found that, when the incident dose on the surface of the skin is 500 J/m2 (290-320 nm) (initial stage of the therapy), the dose producing 50% of the maximal HIV promoter activation (ADUVB50) is limited to the stratum corneum. However, with an incident dose of 5000 J/m2 (an advanced stage of the therapy), ADUVB50) may be delivered as far as the living cells of the epidermis and even to some parts of the upper dermis. For PUVA we found that, when the incident UVA doses are 25 or 100 kJ/m2 (320-400 nm) (an initial and an advanced stage of therapy, respectively), and the 8-methoxypsoralen concentration in the blood is 0.1 microgram/mL (the desired level), the combined doses to the mid epidermis (and some areas of the upper dermis) are well below the 50% HIV promoter-activating PUVA dose (ADPUVA50). Only under the worst scenario conditions, i.e. an exceptionally high drug concentration in the patient's tissues and localization of HIV in the nearest proximity to the skin surface, would the combined PUVA dose expected during photochemotherapy exceed ADPUVA50. These results suggest that the probability of HIV activation in the epidermis by direct mechanisms is higher for UVB than for PUVA treatment. However, complexities of the UV-inducible HIV activation and immunomodulatory phenomena are such that our results by themselves should not be taken as an indication that UVB therapy carries a higher risk than PUVA therapy when administered to HIV-infected patients.

Diet after pancreas transplantation

OBJECTIVE

To determine whether discontinuation of insulin therapy and glucose monitoring and instructions to increase dietary salt and water intake after pancreas transplantation (PTX) resulted in changes in food choices.

RESEARCH DESIGN AND METHODS

All PTX recipients who had completed a preoperative diet record, had received their PTX > 6 months before, had stable pancreas and kidney function, and were on a stable diet were invited to submit a 3-day post-PTX diet record. Of the 14 eligible, 11 agreed to participate and completed the study (2 women and 9 men). Their pre- and post-PTX diet records were analyzed by computer program. Weight, glycohemoglobin, blood pressure, medications, and fasting lipids both before and after PTX were also analyzed.

RESULTS

The recipients were studied 576 +/- 60 days post-PTX, on average. Total calories and BMI were unchanged after PTX. Before PTX, 34% of calories were in fats, 49% in carbohydrate, and 17% in protein with no change in distribution of calories after PTX, although there was a trend toward greater saturated fat intake. Total salt intake was increased after PTX (P < 0.01) because of sodium bicarbonate administration, although dietary salt intake did not change. The HDL cholesterol concentration increased and cholesterol-to-HDL ratio decreased after PTX (P < 0.05), while the remaining lipids were unchanged.

CONCLUSION

Weight, total calories and distribution of calories, and dietary salt were unchanged after PTX, and diet did not explain the changes in HDL cholesterol or cholesterol-to-HDL ratio. These preliminary diet results suggest that greater emphasis on dietary instruction may be needed after PTX.

Apoptosis removes chick embryo tail gut and remnant of the primitive streak

Removal of transient features in morphogenesis of chick embryo tail is by programmed cell death. We used ApopTagTM (Oncor, Gaithersburg, MD) with the peroxidase/diaminobenzidine (DAB) procedure to correlate apoptosis with earlier reports of patterns of cell death in stage HH17-25 embryos, and our results suggest that the cell death inferred with supravital staining and appearance of cells in morphogenesis of the tail bud is programmed cell death called apoptosis. Apoptosis markers in tail bud are most abundant in the median cell cord of occluded degenerating tail gut. Tail bud mesenchyme marks for apoptosis most frequently in the ventrum of older stages, where cell death has been reported. Cells of the remnant of the primitive streak (Hensen's node) mark for apoptosis, suggesting that programmed cell death is a stop signal for axial organization at the caudal terminus. Apoptosis markers in postmembrane cloacal endoderm anticipate the transient cloacal fenestra. Lack of apoptosis markers in neural tube, notochord, and somites supports the suggestion of Schoenwolf ([1981] Anat, Embryol. (Beri.) 162:183-197) that cells of those areas in the tail bud are assimilated into the growing rump of the chick embryo. Lack of markers in neural tube of tail bud formed by secondary neurulation suggests that apoptosis is not involved in cavitation of medullary cord, but further investigation is necessary. A limited investigation of pharyngeal membranes and midgut, where cell death has not been reported to be as important in morphogenesis, did not show apoptosis markers in those tissues (Miller and Briglin [1994] "Cell Death in Development and Cancer," Houston: University of Texas MD Anderson Cancer Center, pp, 82-83). Absence of apoptosis markers in roof of gut tube suggests that the lower frequency of thymidine labeling reported for those cells (Miller [1986] Anat. Rec. 214: 87A) is not a result of apoptosis. Clearly marked cells correlated with expected locations of migrating neural crest and primordial germ cells in these stages, but distribution of apoptosis markers was not abundant or general for either cell type.

Prevalence of modifiable risk factors for sudden infant death syndrome in British Forces Germany

A questionnaire survey was conducted amongst parents in the military community in British Forces Germany to investigate the prevalence of known and suspected risk factors for Sudden Infant Death Syndrome. Over a thousand questionnaires were returned (response rate 58%) and these showed that the prevalence of babies being placed in the prone position to sleep is now extremely low and the use of room thermometers to help control ambient temperature is widespread. However 29% of the mothers had smoked in pregnancy and 44% of households with a new-born baby had at least one parent who smoked. Additional health promotion activity aimed at reducing the prevalence of smoking in pregnancy and amongst the parents of new-born babies is recommended.

Increasing staff knowledge of and improving attitudes toward patients with borderline personality disorder

This study examined the effect of a self-instructional program on nurses' knowledge of and attitudes and behavioral intentions toward patients with borderline personality disorder. The sample consisted of registered nurses working on inpatient psychiatric units of general hospitals: 19 in the experimental group and 13 in the control group. The Questionnaire on Borderline Personality Disorder was administered before and after nurses completed the program. Significant postintervention differences in knowledge of and attitudes toward patients with the disorder were found between the experimental group and the control group. Self-instruction may improve nurses' care of patients with borderline personality disorder.

Experience of FK506 immune suppression in pediatric heart transplantation: a study of long-term adverse effects

BACKGROUND

Immunosuppression with FK506 for pediatric heart transplantation has been used in this institution since 1989. This study reports the unique toxicity of this macrolide agent in these heart transplant recipients.

METHODS

Between October 1989 and August 1994, 49 patients were managed with FK506, which was the initial primary agent in 38 patients. The remaining 11 were switched from cyclosporine A because of persistent rejection or side effects from the cyclosporine A or prednisone. Data were obtained retrospectively from medical records.

RESULTS

Mean duration of follow-up was 29 months (median 37 months, range 3 to 96 months). Twenty-nine patients (59%) were receiving FK506 alone; 20 patients (41%) were receiving additional treatment with azathioprine, prednisone, or methotrexate. There were seven deaths. Twenty patients (41%) had elevated creatinine levels between 1 to 2 mg/dl. Five patients (11%) had levels greater than 2 mg/dl. Two patients with preexisting renal dysfunction while receiving cyclosporine A had chronic renal failure 32 and 36 months after switching to FK506 and required kidney transplantation. Hyperkalemia was a persistent finding in 26 patients. Of eight patients with hypertension, four had preexisting disease while receiving cyclosporine A; two had impaired renal function, and two were receiving prednisone. Severe anemia developed in eight patients (16%), two of whom had parvovirus. Moderate anemia developed in 21 patients (43%). Eosinophilia occurred in 19 patients; 11 of 19 patients (58%) had allergic symptoms. There was one case of diabetes mellitus. There were 12 significant infections with four infection-related deaths. Lymphoproliferative disease was noted in three patients, two of whom survived. Gastrointestinal symptoms, including chronic diarrhea, recurrent abdominal pain, and reflux esophagitis were present in 10 patients.

CONCLUSIONS

In our experience, anemia, renal toxicity, hyperkalemia, chronic diarrhea, and allergies were the most common adverse effects of FK506. Unlike cyclosporine A, hypertension, gingival hyperplasia, coarsening of facial features, and hirsutism were not seen.

The relationship of vibrissal motor cortex unit activity to whisking in the awake rat

Rats actively sweep their whiskers back and forth to locate and palpate objects within their immediate environment. Microstimulation studies in anesthetized rats have demonstrated the presence of a large vibrissal motor representation in agranular cortex. However, the manner in which motor cortex neurons contribute to whisking behavior in the awake animal is unknown. This study represents an initial investigation of the relationship between the activity of task-related neurons in vibrissal motor cortex and the electromyographic (EMG) activity of the deep vibrissal pad muscles in the awake, freely whisking rat. Each animal was gently held in an experimenter's hands while the animal whisked the air. A spring-loaded, metal microelectrode mounted in a removable, miniature microdrive provided stabile recordings of motor cortex unit activity. Fine-wire electrodes implanted in the mystacial pad simultaneously recorded facial muscle activity. Results showed that the discharge of task-related neurons was correlated with changing levels of muscle output. Unit discharge was related in a tonic or phasic-tonic fashion to EMG activity. No units were found to discharge rhythmically in a 1:1 fashion with the periodicity of the whisking pattern. These findings support a role for vibrissal motor cortex in the initiation and modulation of the overall level of mystacial pad muscular output, but not in the generation of bursts of EMG activity responsible for individual whisking sweeps.

The distribution of F13A subtypes in four populations using agarose isoelectric focusing and Western Blot detection

Using an isoelectric focusing gel containing agarose, urea, a separator and a narrow range ampholyte of pH 5-6, a system was designed to split the F13A*1 and F13A*2 alleles into the subtypes 1A, 1B, 2A and 2B. Four population groups (European-Americans, African-Americans, Mexican-Americans and Native-Americans) were data based. Subtyping F13A increased the information content significantly over the previous F13A typing system by doubling the number of alleles and increasing the number of phenotypes from three to ten. The new system has proved to be of value in parentage testing by increasing exclusionary power in cases of non-paternity and increasing the paternity index in non-exclusionary cases. Though there does not appear to be any significant variation among U.S. populations, published data on Japanese populations suggests that significant differences among populations may exist, leading to an anthropological usefulness as well.

Parents' attributions for their children's behavior

Parents' attributions for children's behavior are of interest both as a form of adult social cognition and as possible contributors to children's development. This article reviews work on the determinants and the effects of parents' attributions. Included in the discussion of possible determinants are characteristics of the target (e.g., age and sex), characteristics of the judge (e.g., mothers vs. fathers), and characteristics of the behavior to be explained (e.g., positive or negative). Included in the discussion of possible effects are effects on parents' affect and behavior and on children's development. The evidence suggests that parents do form attributions for their children's behavior and that these attributions vary in predictable (although not perfectly consistent) ways across judges, targets, and outcomes. The evidence also suggests, although less certainly, that attributions affect both parents' behavior and children's development. The review concludes with suggestions for future research.

Occult restrictive hemodynamics after pediatric heart transplantation

BACKGROUND

Although resting hemodynamics after pediatric heart transplantation are generally within normal limits, we hypothesized that occult restrictive hemodynamics suggesting diastolic dysfunction may be unmasked by acute volume loading (fluid challenge) during cardiac catheterization. We wished to determine the incidence of diastolic dysfunction and to assess whether it progressed over time.

METHODS

From 1988 through 1993, a total of 100 fluid challenges were performed at the time of surveillance endomyocardial biopsy in 31 survivors of orthotopic heart transplantation. Cyclosporine-based immunosuppression was used in 16 patients, and FK506 was used in 15 patients. Right heart hemodynamics and cardiac output (thermodilution) were obtained at baseline and after a fluid challenge with 10 ml/kg of normal saline solution. The data were analyzed to determine whether type of immunosuppression or time elapsed since transplantation predicted the response to fluid challenge.

RESULTS

Baseline hemodynamics were normal; however, a marked increase in atrial filling pressures occurred after fluid challenge (p < 0.001). Findings were similar in cyclosporine- and FK506-treated patients. Hemodynamic response to fluid challenge was not related to duration of time since transplantation, including studies on patients surviving more than 4 years.

CONCLUSIONS

Diastolic dysfunction after heart transplantation is common; however, the abnormalities do not progress in severity, suggesting stable long-term graft function.

Neoplastic transformation of neonatal human fibroblasts exposed in vitro to radiation from a quartz-halogen lamp

The use of unfiltered quartz-halogen lamps exposes human skin to radiation that spans much of the ultraviolet (UV) spectrum. Reports indicate that exposure to quartz-halogen lamps is erythemogenic, mutagenic, and carcinogenic. To compare the carcinogenic potential of quartz-halogen lamps with that of other UV sources, we determined the dose dependence for cytotoxicity and neoplastic transformation in neonatal human fibroblasts exposed in vitro to: a 15 W germicidal lamp (primarily 254 nm radiation), a 15 W Cool White fluorescent lamp, and an unfiltered 20 W quartz-halogen lamp. Fluence-survival relationships were multiphasic with linear dose response below about 40% survival, and all three sources produced fluence-dependent transformation as indicated by induction of anchorage-independent growth. Maximum transformation frequencies were observed at fluences of 5-8 J/m2 for the germicidal lamp, 6.3 kJ/m2 for the fluorescent lamp, and 300 J/m2 for the quartz-halogen lamp. These data confirm the carcinogenic potential of the quartz-halogen lamp.

Furocoumarin-photosensitized hydroxylation of guanosine in RNA and DNA

Guanosine hydroxylation was used as a marker for assessing photooxidation of DNA and RNA sensitized by monofunctional and bifunctional furocoumarins. DNA or RNA, treated with sensitizer and UVA light, was enzymatically hydrolyzed, dephosphorylated and then analyzed by reversed-phase HPLC with electrochemical detection. Hydroxylated guanosine, i.e. 8-hydroxy-2'-deoxyguanosine (8-OHdG) or 8-hydroxyguanosine (8-OHG), was quantitated. 3-Carbethoxypsoralen (3-CP) was found to be an efficient photosensitizer for oxidation of guanosine in DNA, resulting in conversion of up to 0.4% of guanosine residues to 8-OHdG. In contrast, dramatically lower levels of guanosine hydroxylation were observed in 3-CP-photosensitized RNA. Psoralen was found to be a more efficient photosensitizer than angelicin in both DNA and RNA. Additional studies of oxidation of 3-CP-photosensitized DNA indicated that double-stranded DNA is 10 times more susceptible to photooxidation than single-stranded DNA, implicating 3-CP binding to DNA as an important mechanistic step in photooxidation of guanosine. The effects of D2O and degassing with argon on photooxidation of guanosine in DNA sensitized by 3-CP were inconsistent with a mechanism involving 1O2. In addition, chelation of adventitious metal ions present in preparations of DNA photosensitized by 3-CP had no effect on hydroxylation of guanosine.

Prospective incidence of photic maculopathy after cataract surgery

PURPOSE/METHODS

To determine the incidence of photic retinal injury during cataract surgery, we studied 37 consecutive patients with intravenous fluorescein angiography within ten days after cataract surgery. The microscope irradiance was standardized for all cases.

RESULTS/CONCLUSIONS

Fluorescein evidence of photic retinal injury did not develop in any of the 37 cataract patients. Incidence rates for photic retinal injury induced by the surgical microscope vary considerably among ophthalmologists and most likely reflect differences in microscope brightness, surgical duration, and surgical technique.

Confidential inquiries into cot deaths in British Forces Germany

Confidential inquiries into cases of cot death in British Forces Germany were introduced in 1990. The information which has been collected so far suggests that the current attention to the position in which a baby is placed in a cot, the prevention of overheating and the avoidance of cigarette smoke, is not misplaced. Despite the considerable reduction in the cot death rate which has occurred in British Forces Germany since 1990 it is recommended that confidential inquiries should be continued so that possible opportunities to further reduce the risks are not missed.

Effect of pedal cadence on parameters of the hyperbolic power-time relationship

The purpose of this study was to evaluate the effect of pedal cadence methodology on the relationship between power output and time to exhaustion. Twenty-four subjects each performed 12 all-out cycle ergometer tests (four at a constant 60 rpm, four at a constant 100 rpm, and four where they were allowed to select and, within each test, vary their cadence). The parameters of the hyperbolic power-time relationship, AWC (anaerobic work capacity) and CP (critical power), were estimated for each pedal cadence methodology using three regression models: nonlinear power-time, linear work-time, and linear power-time-1. In all cases, R2 was high and standard errors of the estimate of AWC and CP were low. With the two constant rpm methodologies, the estimates of AWC and CP were influenced by the choice of regression model. The estimates of AWC and CP were also influenced by the pedal cadence in the all-out tests. For example, the CP derived from the 100 rpm tests (mean +/- SD: 195 +/- 50 W) was lower (p < 0.05) than the CP from the other methodologies (207 +/- 50 W and 204 +/- 48 W), and the AWC from the variable cadence methodology (16.1 +/- 6.2 kJ) was greater than the AWC from constant rpm trials (14.5 +/- 5.9 kJ and 14.6 +/- 5.7 kJ). It is concluded that pedal cadence methodology influences the parameters of the power-time relationship.

Anti-insulin antibodies are a cause of hypoglycemia following pancreas transplantation

OBJECTIVE

Hypoglycemic symptoms have been reported by more than half of pancreas transplantation (PTX) recipients. To better understand the mechanism for the hypoglycemia documented in some of these patients, we studied the glucose and pancreatic hormone response to Sustacal in patients with and without hypoglycemia following PTX.

RESEARCH DESIGN AND METHODS

Twelve patients with established, repeated episodes of hypoglycemia following PTX (hypo) were case-matched to PTX recipients without hypoglycemic symptoms (control; n = 7). On the day of the study, fasting glucose, free and total immunoreactive insulin (IRI), C-peptide, proinsulin, and glucagon were drawn (time 0); Sustacal was administered; and glucose, free and total IRI, and C-peptide were assayed at 15, 30, 45, 75, 120, 150, 180, and 240 min. Based on the glucose response to Sustacal, the hypo group was further divided into those whose glucose rose after Sustacal (hypo-high; n = 7) and those with no increase in glucose from baseline concentration (hypo-flat; n = 5).

RESULTS

Before the administration of Sustacal, the hypo-high group had a lower fasting free/total IRI (0.26 +/- 0.06, mean +/- SE) than the hypo-flat (0.51 +/- 0.02) or control (0.52 +/- 0.04) groups (both P < 0.05 compared with hypo-high). The glucose response to Sustacal was greatest in the hypo-high group as defined. Area under the curve (AUC) for total IRI following Sustacal was also greatest in the hypo-high group (P < 0.05 compared with both control and hypo-flat groups), but there was no significant difference in free IRI AUC following Sustacal between the three groups. Two individuals developed hypoglycemia during the Sustacal challenge, both in the hypo-high group.

CONCLUSIONS

The lower fasting free/total IRI ratio and greater increase in glucose and total IRI in response to Sustacal in the hypo-high group compared with either the hypo-flat or control groups are consistent with the presence of significant quantities of anti-insulin antibodies in the hypo-high group. Because anti-insulin antibodies are, in turn, an established cause of episodic hypoglycemia, this study provides the first data to support the hypothesis that significant quantities of anti-insulin antibodies are a cause of symptomatic hypoglycemia following PTX in some recipients.

Immediate and delayed apoptotic cell death mechanisms: UVA versus UVB and UVC radiation

The mechanism of cell death induced by the different waveband regions of ultraviolet radiation (UVR), i.e., UVA1 (340-400 nm), UVB (290-320 nm) and UVC (200-290 nm) was investigated, using equilethal doses (90% reproductive death) on L5178Y-R murine lymphoma cells. To distinguish between necrosis and apoptosis, the following endpoints were monitored over time using flow cytometry and transmission electron microscopy: percentage of remaining cells, membrane permeabilized cells, dead cells, apoptotic cells, and ultrastructural changes. All waveband regions of UVR were found to cause apoptosis as opposed to necrosis. However, UVA1-induced immediate (0-4 h) apoptosis, while UVB- or UVC-induced delayed apoptosis (<34 h). Moreover, the membrane permeability changes that only result from exposure to UVA1 radiation, especially to red blood cells, suggests that the immediate apoptotic mechanism involves membrane damage. Therefore, the results suggest that there are three death mechanisms available to one cell type: necrosis, immediate apoptosis, and delayed apoptosis (or programmed cell death).

Cyclosporine challenge in the decision of combined kidney-pancreas versus solitary pancreas transplantation

Combined kidney-pancreas transplantation has become the treatment of choice for many patients with end-stage diabetic nephropathy. Pancreas transplantation (PTx) alone is an option for type I diabetic patients without end-stage diabetic nephropathy. Knowledge of factors contributing to or predicting the rate of renal deterioration (including the effect of CsA on the patient's renal function before transplantation) is necessary to determine candidacy for either kidney-pancreas transplantation or PTx alone. To address this issue, we selected 12 pre-uremic patients with creatinine clearances (CrCl) above 40 ml/min and less than 100 ml/min to participate in a 6-week oral CsA challenge test. Serum chemistries, including serum creatinine (SCr) and CsA level, were measured weekly. Urinary protein and CrCl were measured at 0, 2, 4, and 6 weeks. Glomerular filtration rate (GFR) (by 125I-sodium iothalamate clearance) was measured at 0, 3, and 6 weeks. All patients initially received oral CsA at 10 mg/kg/day in 2 divided doses. Doses were adjusted to maintain a 12-hr trough level of 500-1000 ng/ml using a whole blood polyclonal TDX assay. Data are presented as mean +/- SEM and as box-plot graphs. One patient was a CsA challenge test failure because SCr exceeded 3.0 mg/dl despite a reduction in CsA dose and level. Therefore, this patient was not a candidate for PTx alone and was excluded from further analysis. Among the 11 nonfailures, the mean CsA level at 6 weeks was 640 +/- 76 ng/ml. SCr increased from 1.2 +/- 0.1 mg/dl to 1.6 +/- 0.1 mg/dl (33% increase) (P = 0.0001). CrCl decreased from 82 +/- 9 ml/min to 63 +/- 8 ml/min (24% decrease) (P = 0.03). GFR decreased from 95 +/- 15 ml/min to 70 +/- 10 ml/min (26% decrease) (P = 0.009). CrCl and GFR did not differ from one another at 0 and 6 weeks (r = 0.77 and 0.98; P = 0.3 and 0.7, respectively). Urinary protein decreased from 1.0 +/- 0.3 g/day to 0.7 +/- 0.3 g/day at both 4 and 6 weeks (P = 0.03 and 0.06, respectively). Three of the 11 patients have not yet received transplants. Eight patients subsequently received PTx alone and were followed prospectively. Two allografts were lost early to rejection. Six were followed from 5 to 19 months after PTx alone. Serum creatinine and CrCL measurements during the CsA challenge test predicted post-PTx levels: SCr 1.6 +/- 0.1 vs. 1.7 +/- 0.3 mg/dl, P = 0.48, and CrCl 68 +/- 10 vs. 53 +/- 3 ml/min, P = 0.17, respectively.

Paclitaxel (Taxol) treatment for refractory ovarian cancer: phase II clinical trial

OBJECTIVE

Our aim was to determine the efficacy and toxicity of paclitaxel in the treatment of refractory and platinum-resistant epithelial ovarian cancer.

STUDY DESIGN

Eligibility required three prior failed chemotherapy regimens and documented platinum resistance. One hundred patients with advanced ovarian cancer received paclitaxel 135 mg/m2 over 24 hours every 21 days with optional granulocyte colony-stimulating factor support.

RESULTS

Paclitaxel was generally well tolerated. In four patients bowel perforation or fistula developed. After three cycles 34% of patients had stable disease and 25% of patients demonstrated a response, either partial or complete. After six cycles 24% of patients continued to respond. To date, six patients have achieved a complete response.

CONCLUSION

A 25% response rate in patients with refractory ovarian cancer was observed, which was durable to six cycles.

Domains of differential cell proliferation and formation of amnion folds in chick embryo ectoderm

Patterns of cell proliferation in ectoderm epithelium that will form avian amnion correlate with morphogenesis, but not in an obvious pattern with respect to large-scale folding. At sites where the pre-axial amnion folds will first appear in 4- to 8-somite embryos, patterns of proliferation do not separate into domains that presage location of the single pre-axial fold that is commonly described in embryology texts. Instead, increased cell proliferation occurs in a significant, bilateral pattern. In stages with 13 to 27 somites, when lateral amnionic folds are prominent, five paraxial domains of cell proliferation correlate with morphology and show decreasing levels of cell proliferation with distance from the neural axis. Slowly growing areas surround rapidly growing areas and could assist buckling of epithelium by providing constraints on expansion of faster growing areas. Proliferation domains in ectoderm correlate with morphology and morphological events when localized changes in cell shape are lacking and suggest a role for differential cell proliferation in formation of large-scale epithelial folds in early chick embryos.

Program management and health care informatics: defining relationships

The program management (PM) structure is a relatively well-known organizational model for hospitals. A variation of the matrix structure, it allows for an interdisciplinary team of health care providers to facilitate patient care delivery. However, providing such focused care results in a complex, highly information-dependent operational environment. To meet the information needs of such an environment, careful planning in selecting and implementing technology is required. Along with supporting patient care, the technology will also help in managing costs, human resources, quality and utilization, as well as in monitoring performance and outcomes measurement. Focusing specifically on the information technology environment, this article addresses health care informatics (the diverse categories of information and systems) needed to support clinical program managers, executives and others in a PM organization. Examples from both a university-affiliated and a community-based program managed hospital illustrate their approach to PM and information technology.

XeF(+), IF (+), and other unusual ions generated by reactions of hyperthermal ion beams at self-assembled monolayer surfaces

Collisions of atomic and molecular ions (I(+), Xe(+); CH3I(+), I 2 (+) ) with self-assembled fluoroalkyl-monolayer surfaces result in reactions involving the net transfer of fluorine atoms or fluorocarbon radicals from the surface to the projectile ions. The scattered products, which include unusual ionic species such as IF(+), IF 2 (+) CFI(+); CF2I(+), I2F(+), and XeF(+), are generated in endothermic ion-surface reactions. These reactions are not observed when the collision partner is a gas-phase (rather than a surface-bound) perfluoroalkane. Evidence is presented which suggests that in some cases molecular projectiles undergo surface-induced dissociation to yield atomic species which subsequently react with the surface. Fluorine abstraction is favored for projectiles containing highly polarizable elements.

Non-nuclear damage and cell lysis are induced by UVA, but not UVB or UVC, radiation in three strains of L5178Y cells

The potential to induce non-nuclear changes in mammalian cells has been examined for (1) UVA1 radiation (340-400 nm, UVASUN 2000 lamp), (2) UVA+UVB (peak at 313 nm) radiation (FS20 lamp), and (3) UVC (254 nm) radiation (G15T8 lamp). The effects of irradiation were monitored in vitro using three strains of L5178Y (LY) mouse lymphoma cells that markedly differ in sensitivity to UV radiation. Comparisons were made for the effects of approximately equitoxic fluences that reduced cell survival to 1-15%. Depending on the cell strain, the fluences ranged from 830 to 1600 kJ/m2 for the UVASUN lamp, 75 to 390 J/m2 for the FS20 lamp and 3.8 to 17.2 J/m2 for the G15T8 lamp. At the exposure level used in this study, irradiation with the UVASUN, but not the FS20 or G15T8, lamp induced a variety of non-nuclear changes including damage to cytoplasmic organelles and increased plasma membrane permeability and cell lysis. Cell lysis and membrane permeabilization were induced by the UVA1 emission of the UVASUN lamp, but not by its visible+IR components (> 400 nm). The results show that the plasma membrane and other organelles of LY cells are highly sensitive to UVA1 but not to UVB or UVC radiation. Also UVA1, but not UVB or UVC radiation, causes rapid and extensive lysis of LY cells. In conclusion, non-nuclear damage contributes substantially to UVA cytotoxicity in all three strains of LY cells.

Role for differential cell proliferation in perforation and rupture of chick pharyngeal closing plates

Patterns of cell proliferation show two distinct domains around avian pharyngeal closing plates as they form, perforate, and rupture. Pouch endoderm and groove ectoderm are in one domain showing 81-86% proliferation, which suggests relatively rapid growth. Cells in epithelia that comprise the pharyngeal closing plates contiguous with pouch and groove epithelia are vital but are dividing at a significantly lower percentage (62-64%). This phenomenon is similar to the lag in growth reported for cells in the oral membrane around the time of rupture (Miller and Olcott, 1989: Anat. Rec., 223:204-208), is consistent with Waterman's suggestion (1985: Anat. Rec., 211:450-457) that cellular reorganization, rather than massive degeneration, is a major mechanism of initial perforation, and suggests that differential growth is a contributor to performation and rupture of chick pharyngeal closing plates.

Simultaneous subtyping of group specific component and esterase D by isoelectric focusing on agarose gels

A quick, sensitive and economical technique has been developed to subtype GC and ESD simultaneously on the same agarose IEF gel. This method could be a useful tool for forensic application.

Surface-Induced dissociation from a liquid surface

Mass-selected projectile ions in the tens of electronvolt energy range undergo surface-induced dissociation upon collision with a liquid perfluorinated polyether (PFPE) surface. The efficiency of translational-to-vibrational (T-V) energy transfer is similar to that observed for a fluorinated self-assembled monolayer (SAM) surface. The thermometer ion W(CO)^' was used to detenrrine an average T-V conversion efficiency of 18% in the collision energy range of 30-50 eV. The surface can be bombarded for several hours without displaying any change in the scattered ion products. Ion-surface reactions occur with some projectiles and are analogous to those seen with the fluorinated SAM surface. For example, WF ▪ (+) (m=1-5) and W(CO)nF ▪ (+) (n=1-2, m=1-2) are generated upon collisions of W(CO) 6 (+) with the PFPE liquid surface. The ion-surface reactions observed suggest that F atoms and/or CF3 groups are accessible for reaction while the oxygen atoms lie below the outermost surface layer. Chemical sputtering of the liquid surface also occurs and yields common fluorocarbon fragment ions, including CF 3 (+) , C2F 5 (+) , and C3F 7 (+) and the oxygenated product CFO(+). The liquid surface is remarkably free of hydrocarbon impurities. Collisions of the pyrazine and benzene molecular ions, both probes for hydrocarbon impurities, resulted in very little protonated pyrazine or protonated benzene.