A preliminary comparison of two perennially ice-covered lakes in Antarctica: analogs of past Martian lacustrine environments

Perennially ice-covered lakes in the Antarctic have been suggested as analogs to lakes which may have existed on the surface of Mars 3.5 billion years ago. During the 1991-1992 austral summer, a joint Russian/American research effort was directed at studies of ice-covered lakes in the Bunger Hills Oasis, Antarctica (66 degrees S, 100 degrees E). The primary objective of the expedition was to investigate this ice-free area for features analogous to ancient martian environments that may have been capable of supporting life and to compare the ice-covered lakes of the Bunger Hills with those in the McMurdo Dry Valleys of southern Victoria Land (77 degrees S, 166 degrees E) as part of the continuing studies of Antarctic-Mars analogs.

Affective illness in family members and matched controls

As part of the US National Institute of Mental Health Collaborative Program on the Psychobiology of Depression study, a subset of 460 randomly chosen relatives of affectively ill probands were compared to a control group matched by the acquaintanceship method. The rate of major affective disorder in relatives was found to be 36%; the rate among controls was 28%. Relatives were also found to have significantly higher rates of bipolar II disorder, any Research Diagnostic Criteria (RDC) affective disorder and any RDC mental disorder. All of these rates were found to be significantly higher when female relatives were compared with their acquaintances, but only the rate of any RDC mental disorder was higher when this comparison was made in men. The acquaintanceship method enabled the selection of a control group that closely resembled the relatives, probably to the extent of "overmatching". When the match was evaluated to determine whether relatives tended to select comparably ill (or well) acquaintances, this was found to be the case only for alcoholic and never mentally ill relatives.

Compliance with public sector HIV medical care

Despite the availability of free or low-cost public sector human immunodeficiency virus (HIV) health-care services, important inequities in utilization exist. This study examined two measures of compliance with HIV medical care: attendance of scheduled outpatient visits and use of the emergency room. Clients of two public HIV outpatient clinics were followed from time of health-care initiation to either death or the end of the study. The association of race, sex, age, and injection drug use (IDU) with these measures were examined in multivariate logistic regression. Models were adjusted for disease staging at time of entry and for length of follow-up time in clinic. Of 1824 clients followed, 15% failed to attend scheduled visits and 18.1% had at least one emergency room visit. Clients who missed visits were more likely to be African American, to have a history of IDU, and to have a CD4 cell count < 500/mm3 or an acquired immunodeficiency syndrome (AIDS)-defining opportunistic infection at entry. They were also more likely to have > or = 12 months of follow-up time in the HIV clinic, but were less likely to have entered into health care from an early intervention clinic. Clients who had at least one emergency room visit were more likely to be African American, female, IDU, and under 22 years of age; these clients were also more likely to have entered with CD4 < 200/mm3 or with an opportunistic infection, and to have > or = 12 months of follow-up in the clinic.(ABSTRACT TRUNCATED AT 250 WORDS)

A web-based architecture for a medical vocabulary server

For health care providers to share computing resources and medical application programs across different sites, those applications must share a common medical vocabulary. To construct a common vocabulary, researchers must have an architecture that supports collaborative, networked development. In this paper, we present a web-based server architecture for the collaborative development of a medical vocabulary: a system that provides network services in support of medical applications that need a common, controlled medical terminology. The server supports vocabulary browsing and editing and can respond to direct programmatic queries about vocabulary terms. We have tested the programmatic query-response capability of the vocabulary server with a medical application that determines when patients who have HIV infection may be eligible for certain clinical trials. Our emphasis in this paper is not on the content of the vocabulary, but rather on the communication protocol and the tools that enable collaborative improvement of the vocabulary by any network-connected user.

Effective hospital leadership for quality: theory and practice

Hospitals need excellent leadership to be efficient in the use of scarce stakeholder resources and to be effective in the competitive provision of services to multiple customers. This study was conducted with the cooperation of the executive team at a large government-funded hospital in Brisbane. It focused on understanding the conceptual models of leadership held by members of the executive and comparing this model with an externally derived model of leadership. Performance on the local model was estimated by cross-linking performance assessment on the external model. Members of the executive espoused, and were also rated by others in the hospital as practising, to a moderate degree, a transformational style of leadership. An overall evaluation of quality practice in the hospital revealed the use of data, the understanding of processes and the formation of supplier partnerships as the areas of hospital activity most limiting the ability to improve. The implications of the conceptual model and performance levels are discussed in relation to the introduction of quality management practice in the hospital, and in terms of management development. A complementary paper focusing on quality implementation as perceived at different staff levels in the hospital is in preparation.

Crystal structure of scytalone dehydratase--a disease determinant of the rice pathogen, Magnaporthe grisea

BACKGROUND

Rice blast is caused by the pathogenic fungus,-Magnaporthe grisea. Non-pathogenic mutants have been identified that lack enzymes in the biosynthetic pathway of dihydroxynapthalene-derived melanin. These enzymes are therefore prime targets for fungicides designed to control rice blast disease. One of the enzymes identified by genetic analysis as a disease determinant is scytalone dehydratase.

RESULTS

The three-dimensional structure of scytalone dehydratase in complex with a competitive inhibitor has been determined at 2.9 A resolution. A novel fold, a cone-shaped alpha + beta barrel, is adopted by the monomer in this trimeric protein, burying the hydrophobic active site in its interior. The interactions of the inhibitor with the protein side chains have been identified. The similarity of the inhibitor to the substrate and the side chains involved in binding afford some insights into possible catalytic mechanisms.

CONCLUSIONS

These results provide a first look into the structure and catalytic residues of a non-metal dehydratase, a large class of hitherto structurally uncharacterized enzymes. It is envisaged that a detailed structural description of scytalone dehydratase will assist in the design of new inhibitors for controlling rice blast disease.

Traumatic tear of tela choroidea resulting in fatal intraventricular hemorrhage

A 39-year-old man was rendered comatose after being struck repeatedly on the head in an altercation. After admission to the hospital, he had computed tomographic scan evidence of diffuse intraventricular and subarachnoid hemorrhage as well as cerebral edema. He shortly thereafter became "brain dead" and life-support systems were discontinued the following day. At autopsy, he had a swollen brain as well as evidence of intraventricular and subarachnoid hemorrhage. No aneurysm or other grossly obvious cause for the hemorrhage was detected. There was, however, a small laceration of the lateral wall of the right lateral ventricle in the region of the caudate nucleus and thalamus, the choroid plexus was detached bilaterally, and the fornices were separated from the corpus callosum. Microscopically, there was further evidence of disruption of the lateral wall of the lateral ventricles, with fragments of ependymal lining mixed in with choroid plexus as well as blood between the fronds of the choroid plexus, and blood dissecting along the wall of the lateral ventricle deep to the ependyma. These findings were felt to be consistent with the recently proposed thesis that tears of the tela choroidea, as part of a so-called inner cerebral trauma, might produce intraventricular and subarachnoid hemorrhage, which, in this case, proved to be fatal.

Prognostic effect of the variable course of alcoholism on the 10-year course of depression

OBJECTIVE

The purpose of this study was to examine the predictive effect of the clinical activity of patients' alcohol use on the course of major depressive disorder.

METHOD

One hundred seventy-six probands with Research Diagnostic Criteria (RDC) diagnoses of both major depressive disorder and alcoholism were compared to 412 probands with major depressive disorder only by using 10 years of short-interval, prospective follow-up data collected as part of the National Institute of Mental Health Collaborative Depression Study. The course of depression was examined by using intensity analysis to represent transitions between states of major depressive disorder. The effect of patients' RDC alcoholism status on the long-term course of major depressive disorder was examined by stratifying the analyses by three levels of alcoholism--never alcoholic, not meeting criteria for current alcoholism, and current alcoholism.

RESULTS

Depressed probands who were either never alcoholic or currently nonactive alcoholic had twice the likelihood of recovery from major depressive disorder than did actively alcoholic depressed probands. The three levels of alcoholism did not differentially predict recurrence of major depressive disorder.

CONCLUSIONS

These findings provide long-term, empirically derived evidence for the deleterious effect of current alcoholism on recovery from depression. The lack of a differential effect of the three levels of alcoholism on recurrence of major depressive disorder suggests that other factors may have greater predictive value.

Team approach to charting: medical staff join in

At British Columbia's Prince George Regional Hospital, collaboration between the hospital's chief of medical staff and its manager of health records has resulted in more meaningful, accurate, timely and complete patient records. The hospital departed from the traditional process of deficiency flagging to physician ownership and ultimate accountability for medical charting.

Cervical carcinoma in women less than 35 years of age

We retrospectively studied 80 patients, less than 35 years old, who were being treated for invasive cervical carcinoma at Charity Hospital of Louisiana in New Orleans. The period covered by the study was March 1980 to November 1989. The study group represented 9.3% (80/862) of the total patients seen with the disease. Disease stage was IB in 50 patients, IIA in 4, IIB in 14, IIIA in 5, IIIB in 6, and IVA in 1 patient. Histopathologic classes included 74 squamous cell carcinomas, 3 adenosquamous carcinomas, 2 adenocarcinomas, and 1 anaplastic carcinoma. Treatment used was either radical hysterectomy, irradiation alone, or irradiation followed by hysterectomy. Five-year actuarial survival rates were as follows: stage IB, 81.6%; stage IIA, 25.0%; stage IIB, 29.8%; stage IIIA, 20.0%; and stage IIIB, 33.4%. The only patient with stage IV cancer died of disease. Our findings do not reveal a relationship between age and survival in stage IB carcinoma of the cervix, and the numbers in the other stages are too small to comment on.

Preliminary crystallographic studies on scytalone dehydratase from Magnaporthe grisea

Magnaporthe grisea are pathogenic, directly penetrating fungi which cause rice blast disease. Isolated, non-pathogenic mutant strains which are defective in the biosynthesis of dihydroxynapthalene-derived melanin fail to infect host plants and have been shown to lack certain key enzymes in melanin biosynthesis. One such enzyme is scytalone dehydratase that converts scytalone to 1,3,8-trihydroxy-naphthalene. Crystallization trials of scytalone dehydratase were undertaken with the expectation that structural information on this enzyme would facilitate design of high affinity inhibitors which might find use in the control of rice blast disease. We now report that recombinant scytalone dehydratase, complexed with a tight binding inhibitor, has been crystallized with PEG 4000 as a precipitant. The crystals are trigonal and belong to the space group P321 with the cell dimension: a = b = 75.5 A, c = 73.8 A. The observed diffraction extends to 2.5 A. Analysis of the packing in the cell suggests that scytalone dehydratase forms a symmetric trimer. These results are consistent with sedimentation equilibrium experiments indicating that the solution aggregation state of scytalone dehydratase was trimeric over a 24,000-fold concentration range.

Impact of Schistosoma haematobium infection and of praziquantel treatment on anaemia of primary school children in Bertoua, Cameroon

There is some debate as to the extent to which Schistosoma haematobium haematuria may be the cause of anaemia. Our goal was to evaluate the impact of a single 40 mg kg-1 dose of praziquantel on anaemia. Since praziquantel does not reduce the hookworm intensity of infection (a major cause of anaemia in children in the area) changes in the prevalence of anaemia in the study population should be due only to the elimination of S. haematobium. Seven hundred and seventy-one primary schoolboys from Bertoua (East Cameroon) were divided into four groups: high infection, moderate infection treated with praziquantel or placebo, and non-infected. Haemoglobin concentrations of the children were determined at the onset of the study and 6 months after the praziquantel intervention. Mean haemoglobin concentrations were not significantly different for no infection or for mild or heavy infection by S. haematobium. A factorial analysis of variance using S. haematobium intensity of infection, malaria and intestinal parasite infections and age as independent variables and haemoglobin concentration as the dependent variable show that only age and malaria infection show a significant relationship with haemoglobin concentration. Despite treatment with praziquantel, all the children in the treatment groups had lower mean haemoglobins 6 months after intervention. A factorial analysis of variance using age, malaria infection and the treatment category as independent variables and the difference in haemoglobin concentration as the dependent variable shows that only malaria infection showed a significant relationship with haemoglobin concentration.(ABSTRACT TRUNCATED AT 250 WORDS)

The topography of muscle activity in quantitative EEG

Ten normal preadolescent subjects were studied on three occasions with quantitative EEG topography: two sessions recorded EEG that was free of artifact, but during the third the subjects were instructed to clench their teeth and tighten their faces to produce muscle artifact. The sessions were then compared for stability of various frequencies at standard scalp electrode sites. The posterior electrodes were stable among sessions for frequencies up to 24 Hz; the anterior electrodes were less stable, and above 24 Hz there were no stable electrode sites. Muscle artifact contaminates anterior electrode sites more than posterior sites, making the posterior scalp electrodes superior for studying beta activity in quantitative EEG. Frequencies above 24 Hz are contaminated at all sites and therefore cannot be assessed reliably in the presence of muscle artifact.

Worksite smoking control, discouragement, and cessation

Smoking control, discouragement, and cessation were investigated at three comparable chemical plants. One plant was randomly assigned to smoking cessation only while the other two plants were assigned to a comprehensive program of smoking control, discouragement, and cessation. Three weeks later, smoking cessation was provided at all three sites. Results are consistent with a previous investigation of the comprehensive program carried out at two oil refineries. Not only was there a greater rate of participation in the smoking cessation program with the comprehensive program, 4 months after completion of smoking cessation treatment revealed significant changes on all outcome variables in the expected direction and suggest the superiority of a comprehensive program of smoking control, discouragement, and cessation over cessation alone.

Methodological issues in linkage analyses for psychiatric disorders: secular trends, assortative mating, bilineal pedigrees. Report of the MacArthur Foundation Network I Task Force on Methodological Issues

A Task Force was assembled to address three data problems in genetic linkage analyses: (1) a secular trend, e.g. cohort effect; (2) positive assortative mating, and (3) bilineal pedigrees. All are cited as reasons for failure to replicate genetic linkage reports. However, we knew of no work demonstrating that these factors could invalidate or bias linkage analyses, nor that they were complications (e.g., variable age of onset). The Task Force concluded that these factors can reduce the power of linkage analyses and result in bias in the estimate of the recombination frequency due to the fact that they represent 'noise' in the system. There was little evidence that the three factors would invalidate a linkage analysis or be directly responsible for negating a linkage finding.

A twin study of genetic and environmental contributions to liability for posttraumatic stress symptoms

We studied 4042 Vietnam era veteran monozygotic and dizygotic male twin pairs to determine the effects of heredity, shared environment, and unique environment on the liability for 15 self-reported posttraumatic stress disorder symptoms included in the symptom categories of reexperiencing the trauma, avoidance of stimuli related to the trauma, and increased arousal. Quantitative genetic analysis reveals that inheritance has a substantial influence on liability for all symptoms. Symptoms in the reexperiencing cluster and one symptom in the avoidance and numbing cluster are strongly associated with combat exposure, and monozygotic pairs are more highly concordant for combat exposure than dizygotic pairs. By fitting a bivariate genetic model, we show that there are significant genetic influences on symptom liability, even after adjusting for differences in combat exposure; genetic factors account for 13% to 30% of the variance in liability for symptoms in the reexperiencing cluster, 30% to 34% for symptoms in the avoidance cluster, and 28% to 32% for symptoms in the arousal cluster. There is no evidence that shared environment contributes to the development of posttraumatic stress disorder symptoms.

Maternal behavioural risk factors for severe childhood diarrhoeal disease in Kinshasa, Zaire

This study examines the relationship between severe diarrhoeal disease and maternal knowledge and behaviours related to hygiene and sanitation. Some 107 paediatric cases admitted to two hospitals in Kinshasa, Zaire in 1988 were matched on age and nearest-neighbour status to 107 controls. Personal interviews and observational methods were used to assess knowledge and behaviours related to hygiene and sanitation. Cases and controls had equivalent socioeconomic status, demographic profiles and access to water and sanitation facilities. However, cases generally exhibited lower levels of knowledge and less sanguine sanitary practices than did controls. Of particular interest was the finding that very specific behavioural items distinguished cases from controls. The disposal of the child faeces and household garbage and mother's knowledge that poor caretaker cleanliness was a cause of diarrhoea in children showed the strongest associations with risk of diarrhoea. There was an exponential relationship between the number of these items a mother answered incorrectly and the odds of diarrhoeal disease. The risk attributable to these three variables was as high as 70%. These findings provide further support for the view that focused educational interventions may have a substantial impact on the occurrence of severe diarrhoeal disease in low-income countries.

Secular trends in lifetime onset of MDD stratified by selected sociodemographic risk factors

We used multivariate proportional hazards (Cox) models to investigate the effects of cohort of birth on age of first onset of major depression measured independently at two occasions, about six years apart, in the first degree relatives of probands with major affective illnesses. We estimated the cohort trends in strata defined by sociodemographic and other measures, to see if the cohort trends are the same across strata. Graphical summaries of the trends reveal a generally consistent pattern of increasing rates and earlier age of onset with successive birth cohorts, across all strata examined. The relatives with a divorced parent had a somewhat delayed secular increase, suggesting either a ceiling effect or an interaction of the two risk factors (recent cohort of birth and divorced parents) such that the combined effect is less than the sum of the individual effects. Otherwise, the cohort effect is persistent and ubiquitous in this sample.

The impact of Schistosoma haematobium infection and of praziquantel treatment on the growth of primary school children in Bertoua, Cameroon

Our objective was to determine in a Cameroonian school population the effect of mild to moderate S. haematobium infection intensity on growth and development of children before and 6 months after praziquantel treatment. Previous studies have yielded contradictory results. Children from Bertoua schools were divided into four study groups: heavily infected (> 500 eggs 10 ml-1), moderately infected (1-499 eggs 10 ml-1) treated with praziquantel, a similar group treated with placebo, and an uninfected control group. Anthropometric measures--height for age per cent median (HAPM), and weight for age per cent median (WAPM)--were significantly higher among the uninfected children. Stepwise regression analysis showed that S. haematobium and Ascaris infections were the strongest predictors of the HAPM with hookworm and malaria infections playing a lesser role. Post treatment comparison of the praziquantel treatment group and the placebo group showed no significant differences for the anthropometric indicators except for mid-arm circumference. Longer observations of growth after treatment as well as monitoring of the rate of reinfection would be necessary to understand better the effect of S. haematobium on growth.

Phototherapy with broad spectrum white fluorescent light: a comparative study

The principles of photobiology suggest that the antidepressant effect of phototherapy depends on the dose and spectrum of light. We investigated the effect of spectrum by comparing two broad spectrum fluorescent light sources with different spectral distributions. In a crossover design, 11 patients with seasonal affective disorder (SAD) were treated with broad spectrum fluorescent and cool white light for 7 days. Scores on the Hamilton Rating Scale for Depression were reduced from 22.5 to 8.1 with broad spectrum fluorescent light and from 23.5 to 8.8 with cool white light. The results suggest that both light sources are effective treatments.

Smoking control and smoking rate: implications for worksite smoking cessation

Amount of control of smoking at three comparable chemical plants was associated with smoking rates. Using a self-report survey, smoking rates were assessed at the three plants. Company authorities were asked about smoking control policy and the extent to which smoking was controlled at each of the three plants was observed. A judgment was made that one plant had a very strict smoking control policy while the other two had moderate policies of control. Smoking rate was then compared for each of the three companies. The company with the strongest smoking control policy had a significantly lower mean rate of smoking than the other two companies. Smoking control may serve to facilitate cessation on the worksite.

Polyamines in the anemia of end-stage renal disease

The improvement in the anemia in patients with end-stage renal disease (ESRD) on continuous ambulatory peritoneal dialysis (CAPD) suggests that dialyzable substances present in the sera of uremic patients either inhibit erythropoiesis directly or inactivate erythropoietin (EPO). In the present study predialysis sera from patients with ESRD inhibited erythroid colony (CFU-E) (N = 10) formation to a significantly (P less than 0.01) greater degree than granulocyte-macrophage (CFU-GM) (N = 7) colony formation in mouse bone marrow (MBM) cultures. The polyamines spermine (SP) (18 to 560 nm/ml) and spermidine (SD) (4 to 648 nm/ml) exerted a more significant (P less than 0.05) inhibition of CFU-E (N greater than or equal to 5) than that of CFU-GM (N greater than or equal to 5) growth. Concentrations of 0.80, 1.0, and 1.5 nm/ml of putrescine (PU) were 92%, 85%, and 77% of erythroid colony (CFU-E) controls (N = 4) and 104%, 130%, and 127% of CFU-GM controls (N = 4). Putrescine (PU) at 1.5 nm/ml also produced a significant (P less than 0.05) inhibition of CFU-E, whereas CFU-GM were stimulated by PU. These data suggest that predialysis sera from uremic patients, as well as SP, SD, and PU, are selectively more inhibitory to CFU-E than CFU-GM growth. The immunoreactivity of EPO was not significantly changed when it was coincubated with SP, SD and PU and measured by radioimmunoassay. PU was found to inhibit noncompetitively the bioactivity of EPO in a CFU-E assay. These data support the hypothesis that polyamines may be important uremic toxins in the anemia of ESRD.

Amino-terminal amino acid sequence of beef heart mitochondrial coupling factor B

Bovine heart mitochondrial coupling factor B was isolated and purified to homogeneity in its active form. The amino-terminal amino acid sequence of the alkylated protein was determined. Two chains with exactly the same sequence except for the presence of an additional Phe at the amino-terminus on one of them were obtained. The 55 amino acid sequence appears to be largely hydrophilic with several charged amino acid residues. This sequence showed no homology with the E. coli unc operon, oligomycin sensitivity conferring protein, or coupling factor 6 or any protein in the data base.

Monotone smoothing with application to dose-response curves and the assessment of synergism

A spline-based procedure for monotone curve smoothing is proposed and is illustrated by application to dose-response curves. It is then shown how such smoothing can be applied to assess possible synergism or antagonism of two drugs.

Ocular effects and detection in tears of aerosolized intranasal cocaine and fluorescein

Ocular effects of intranasal cocaine were investigated. Twenty-nine outpatients from an otolaryngology clinic received 1 mL of aerosolized cocaine 4% (40mg) in each nostril. Intraocular pressure, corneal sensitivity, pupil size, and tear cocaine concentration were assessed before and after cocaine administration. Pupil size was unchanged; intraocular pressure increased in 75% of patients (not statistically significant). Corneal sensitivity decreased by 11% (P less than .05). Cocaine, however, was not detectable in tears using high-performance liquid chromatography. Since corneal sensitivity decreases after intranasal cocaine administration, it may travel retrograde through the nasolacrimal duct. In addition, three pathways of pharmacologic absorption using fluorescein were explored because of its ease of detection. We measured tear fluorescein concentrations in five patients undergoing intravenous angiograms with fluorescein 25% and in six patients who received aerosolized fluorescein 2% intranasally. Fluorescein concentration was 29 times higher per mg dose in intranasal subjects. This finding suggests that reflux occurs through the nasolacrimal duct.

Risk factors of gastric precancerous lesions in a high-risk Colombian population. II. Nitrate and nitrite

Gastric nitrite content was studied in relation to precancerous lesions of the stomach in a case-control study conducted in a high-risk Colombian population. The proportion of detectable nitrite in gastric juice and the mean pH were significantly higher among those with precancerous lesions (chronic atrophic gastritis, intestinal metaplasia, and dysplasia) than among the controls (normal and superficial gastritis); the proportion and mean pH increased with the progression of histological changes from normal to dysplasia. Nitrite was not detectable in gastric juice with a pH less than 5.0. A positive association was found between the proportion of detectable nitrite and the risk of gastric precancerous lesions. Odds ratios of 4.39 for intestinal metaplasia and 24.72 for dysplasia remained significant after controlling for confounders. This finding suggests that nitrite may be a precursor of a mutagen that targets gastric epithelial cells.

Isolation and characterization of canine distemper virus nucleocapsid variants

Nucleocapsid (NC) variants expressed by the Onderstepoort strain of canine distemper virus (CDV) were ultrastructurally and biochemically characterized. Three isolated variants were defined which corresponded to the three variants observed within the cytoplasm of infected cells. Dense NC (D-NC), isolated on discontinuous caesium chloride (CsCl) isopycnic gradients, had an average density of 1.2971 +/- 0.0042 g/ml. Ultrastructurally, D-NC were 1620.0 +/- 112.1 nm in length with a 20.1 +/- 1.3 nm outer and a 5.8 +/- 0.7 nm inner core diameter. The D-NC protein composition was 89.7% of a 61K protein (N), 8.4% of a 75K protein (P) and 1.9% of a 160K to 200K protein (L). A single species of nucleic acid, 15 kb in length, was isolated from D-NC. Light NC (L-NC), similarly isolated, had an average density of 1.2894 +/- 0.0040 g/ml. L-NC differed ultrastructurally from D-NC in that poor resolution of NC subunits, a larger outer diameter (32.0 +/- 2.8 nm), and a greater inner core diameter (10.4 +/- 0.6 nm) were observed. The average L-NC strand length was 1574.4 +/- 115.8 nm. The protein composition was the same as D-NC with the exception of an additional 70K protein, representing 4.0 to 7.7% of the total L-NC protein mass. A 15 kb nucleic acid was also identified in L-NC, although heightened sensitivity of encapsidated L-NC nucleic acid to non-specific nuclease degradation was observed. The ratio of D-NC to L-NC isolated from individual virus preparations varied and was independent of viral infectivity. A third NC variant, defective-NC (Df-NC), was also identified. This had the lowest density on CsCl gradients (1.2460 +/- 0.0046 g/ml). The Df-NC structures were truncated to a uniform length of 87.0 +/- 5.8 nm. Diameter measurements were between those of D-NC and L-NC, being 24.4 +/- 1.4 nm (outer) and 6.9 +/- 0.4 nm (inner core). Like L-NC, the 70K protein was present but in greater amounts, representing as much as 43.7% of the total Df-NC protein mass. RNase A-sensitive nucleic acid was isolated from Df-NC which ranged in size from 1.16 to 0.67 kb with a majority of the material being 0.86 kb in length. For both L-NC and Df-NC, canine CDV convalescent serum reacted with viral N and P proteins in Western blot analyses but not with the 70K protein, suggesting a host cellular origin for the latter.

Rapid isolation of morbillivirus nucleocapsid for genomic RNA cDNA cloning and the production of specific core protein antisera

A procedure is described for the rapid isolation of canine distemper virus nucleocapsid, free from contaminating viral non-core and host cellular proteins. Nucleocapsid isolated in this manner is amenable to ultrastructural evaluation, protein isolation for the production of monospecific hyperimmune serum, and genomic RNA isolation for cDNA cloning. Nucleocapsid (NC) and a defective NC variant (Df-NC) isolated from 5.5 x 10(7) Vero cells infected with Ond-CDV is readily visualized on cesium gradients. The calculated density for NC is 1.2976 +/- 0.0033 g/ml and 1.2458 +/- 0.0056 g/ml for Df-NC. Ultrastructurally, NC appears as long uninterrupted strands, 1.6 +/- 0.1 microns in length, 21.2 +/- 1.7 nm in diameter, with well defined capsid subunits. Df-NC are truncated with a uniform length of 85.8 +/- 7.1 nm and a 24.5 +/- 1.3 nm diameter. A total of 2.1 +/- 0.2 mu of NC protein is obtained for every 1 x 10(6) cells infected; 89.7% of this mass is represented by a 61 kDa protein (N), 8.4% by a 75 kDa protein (P), and 1.9% by a 160-200 kDa protein (L), which is in agreement with the NC constituency of other paramyxoviruses. Viral N and P proteins, purified by 7.5% SDS-PAGE, were used in the production of hyperimmune serum. Specificity was demonstrated by Western blot analysis. Both antisera were capable of detecting viral antigen in persistently and lytically CDV infected cells by indirect immunofluorescence. A single high molecular weight species of nucleic acid was isolated from purified nucleocapsids compatible with a 14.6 kb morbillivirus genome. Although the efficiency of RNA extraction from purified NC was low (14.2%), sufficient RNA was obtained for gel analysis and the establishment of genomic RNA cDNA clones.

Determining zygosity in the Vietnam Era Twin Registry: an approach using questionnaires

The Vietnam Era Twin Registry (VETR) is a registry of 7375 American male veteran twin pairs born between 1939 and 1955 who served in the armed forces of the United States between 1964 and 1975. Optimal use of registry data requires the determination of zygosity. Two approaches are available: analysis of blood genetic marker systems and responses of twins to questions about sibling similarity. Zygosity for the VETR was determined using the questionnaire technique supplemented with blood group typing data abstracted from military records. After comparing four alternative zygosity assignment methods, a logistic regression technique which uses discriminating variables based on race was selected. The approach is similar to that described by Magnus et al. (1983) in their study of Norwegian twins, suggesting that questionnaire responses are independent of nationality and reinforcing the reliability of the questionnaire method for zygosity ascertainment.

NIMH Collaborative Program on the Psychobiology of Depression: clinical

As part of the National Institute of Mental Health Collaborative Program of Depression study, data were collected on 2,225 first-degree relatives of 612 probands. A subset consisting of 187 families of bipolar patients was made available to participants of Genetic Analysis Workshop 5 (GAW5). A description of these data, including sample sizes, diagnoses, and a summary of published analyses, is given.

Genetic analysis of the affective disorders: summary of GAW5

Participants in the Affective Disorders component of Genetic Analysis Workshop 5 had access to five distributed data sets: 1) 187 families from the Collaborative Depression Study, 2) 202 families ascertained as part of the NIMH Family Studies on Affective Disorders, 3) a compilation of 46 pedigrees informative for X-linked markers, 4) HLA typing on 116 kindreds from the Toronto-Rochester Depression Study, and 5) 81 members of an Old Order Amish pedigree demonstrating linkage to markers on chromosome 11p. These databases are each summarized after a brief account is given of the genetics of the affective disorders and commonly used diagnoses. The emphasis of the Workshop was methodologic, with contributions divided evenly between linkage and nonlinkage applications. Contributions are summarized under four substantive areas: regressive logistic models, segregation and other familial analyses, methodologic considerations in linkage analysis, and the relationship between HLA and affective disorders.

Segregation and linkage analyses of bipolar and major depressive illnesses in multigenerational pedigrees

Data were collected on six large multigenerational pedigrees, four ascertained through a proband with major depression and two ascertained through a proband with a bipolar form of illness. Diagnoses were made using the SADS-L structured interview and Research Diagnostic Criteria (RDC). Complex segregation analyses were conducted on the bipolar and the major depression pedigree sets using a model allowing for both major locus and polygenic inheritance; in these analyses a variety of diagnostic schemes and assumptions concerning the lifetime population prevalence were examined. Linkage analyses on standard markers were conducted using parameters for transmission of susceptibility to illness derived from the segregation analyses. Results of the segregation analyses were quite sensitive to the diagnostic and prevalence assumptions. In the pedigrees ascertained through probands with a bipolar form of illness, we were unable to discriminate between major gene and polygenic inheritance. The data were compatible with Mendelian major gene transmission of susceptibility to illness when bipolar and schizoaffective manic diagnoses were considered as affected and the lifetime population prevalence was between 0.04 and 0.06. Outside this narrow prevalence range, or when additional diagnoses, such as major depression or hypomania, were included as expressions of liability to disease, major gene transmission of susceptibility to disease could be rejected. Similarly, in the pedigrees ascertained through probands with major depression, it was not generally possible to discriminate between major gene and polygenic transmission of susceptibility to illness. For a diagnostic scheme including only major depression as a manifestation of susceptibility to illness, there was a narrow range of lifetime population prevalence values (female prevalence ranging from 0.20 to 0.25, male prevalence set to 1/2 female prevalence) which yielded results compatible with major gene transmission. Linkage analyses for all markers yielded negative or inconclusive results. In one bipolar pedigree a lod score of 1.65 was found with a marker in chromosome 1 recommending further studies of this chromosome.

Alterations in cholinergic muscarinic and somatostatin binding sites in a patient with idiopathic intestinal pseudo-obstruction

We present a comparative study of cholinergic muscarinic and somatostatin binding sites on isolated membranes from mucosa and tunica muscularis of normal and dilated parts of the proximal jejunum obtained at surgery from a patient with idiopathic intestinal pseudo-obstruction (IIP) syndrome. We found a statistically significant diminution of cholinergic muscarinic and somatostatin binding sites in mucosa taken from the dilated part of the jejunum, compared with those taken from the normal part. Tunica muscularis of the dilated part of the jejunum contained a significantly higher concentration of peripheral cholinergic muscarinic binding sites (M2) than the normal part did, whereas concentration of M1 cholinergic muscarinic and somatostatin binding sites was similar in both examined parts. These results indicate that IIP-syndrome may be related to alterations in cholinergic muscarinic binding sites in the tunica muscularis of the intestine.

School-aged children of depressed parents: a blind and controlled study

This study examines the prevalence of psychiatric dysfunction in the children of parents diagnosed with affective disorders. Sixty children from 37 proband families were compared to 43 children from 26 families obtained from matched controls as well as 20 children from 13 medically ill families. Group differences in diagnosable childhood disorders and familial characteristics are investigated. Significantly more disorders and symptoms were noted in the children with psychiatrically ill parents as compared to children from matched controls and medically ill parents. Using logistic and Cox survival analyses, correlates for the risk of affective disorder, attention deficit and conduct disorder in the children were examined. Maternal depression and paternal alcoholism were related to the risk for depression in the child. The child's sex and the presence of affective disorders in the father were significantly related to the risk for attention deficit disorder. Maternal alcoholism, parental divorce and the type of subject (proband or control family) were significantly related to the risk for conduct disorder. The findings are discussed relative to results from earlier studies on rates of disorder in the offspring of depressed parents.

Early detection of carpal erosions in patients with rheumatoid arthritis: a pilot study of magnetic resonance imaging

A pilot study comparing standard radiography to magnetic resonance imaging (MRI) was performed on the wrists of 10 patients with early (anatomic Stage I or II) rheumatoid arthritis (RA). MRI was found to be superior to standard radiographs in 2 respects: (1) synovial inflammation was impressively demonstrated on T2 weighted images, whereas plain films merely suggested soft tissue swelling; and (2) T1 and T2 weighted images clearly revealed erosions of several carpal bones which were not noted on standard radiographs. Although the expense of MRI currently precludes its routine use in clinical practice, the apparent sensitivity of this diagnostic modality for detecting early changes in RA might make it an invaluable tool for therapeutic decision making or for assessing response in interventional trials.

Gastric, duodenal, and pancreatic somatostatin-like immunoreactivity during hypovolemic shock

Because hypovolemic shock is known to cause gastric ulcers in animals and human beings, we investigated the tissue levels of somatostatin-like immunoreactivity (SLI) in the gastric corpus and antrum, duodenum, and pancreas during hypovolemic shock in rats. We studied male Wistar rats (N = 10 each) 15 min, 2 hr, and 12 hr after hypovolemic shock and compared results to a control group (N = 15). Two rats in both 2-hr and 12-hr groups showed gastric ulcers: three corporal and one antral. One animal developed multiple ulcers. In the gastric corpus and antrum and in the duodenum, tissue SLI showed significant decrease 15 min and 2 hr after shock. Gastric SLI remained low, whereas duodenal SLI recovered and rose above control level at 12 hr. Pancreatic SLI showed no significant changes during hypovolemic shock. Gastric tissue SLI levels that were significantly lower after shock than those of normal controls may have contributed to the peptic ulcer disease induced by hypovolemic shock in this experimental model.

Popliteal vascular injuries and war: are Beirut and New Orleans similar?

Trauma to the lower extremity associated with fracture and vascular injury has a high reported incidence of limb loss. This study reviews and contrasts the experience at Tulane University affiliated hospitals (TU) and the American University of Beirut (AUB) (1980 to 1984), both of which are surrounded by hostile action. Seventy-six male patients (28--AUB, 48--TU) with an average age of 21.2 (TU) and 24.4 (AUB) years (range, 17 to 42) presented with popliteal artery injuries with (34 [14--AUB; 20--TU] ) and without (42 [14--AUB; 28--TU]) associated fractures. All patients were clinically evaluated, angiogrammed, begun on cephalosporin antibiotics, and operated upon. Fractures were treated with extraskeletal fixation or splinting. Time of initiation of operative therapy varied from less than one to greater than 12 hours. When necessary, contralateral limb reversed saphenous vein was used as an interposition graft. Fasciotomies were done for popliteal artery injuries with greater than 6 hours' ischemic time, and combined popliteal artery and popliteal vein injuries. Nine limbs of 76 at risk were amputated: 5/34 (2/14--AUB; 3/20--TU) with popliteal injuries and fractures, and 4/42 (1/14--AUB; 3/28--TU) with popliteal injuries and without fractures. Five of the amputated limbs had initiation of therapy at greater than 12 hours; three had initiation of therapy at greater than 8 hours. Good communication between surgeons, prompt fracture reduction, antibiotics, angiography, and total repair of the vascular injury resulted in limb salvage in 30/40 patients with popliteal artery injury and fracture, and in 39/42 patients with popliteal artery injury without fracture.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of C3 deposition and degradation on bacterial surfaces after opsonization

C3b and iC3b, opsonic fragments of C3, interact with specific receptors on phagocytic cells. After bacterial opsonization, C3 fragments were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, western blotting, and immunodetection. For bacteria opsonized in 50% pooled human serum (PHS), C3 deposition and cleavage to iC3b occurred rapidly. C3b, iC3b, and C3d made up 17%, 64%, and 19%, respectively, of the C3 on Staphylococcus aureus and 53%, 44%, and 2% respectively, on Escherichia coli. Residual C3b was refractory to factor I cleavage, an occurrence enabling alternative pathway activation to continue. C3 deposited was quantitated by enzyme-linked immunosorbent assay; with 50% PHS, greater than 50% and 90% of total C3 deposition occurred within 5 and 10 min, respectively. With a lower percentage of PHS, maximal deposition required up to 60 min and was not achieved in less than 10% PHS. Ester-bound fragments represented 34% and 82% of covalently bound C3 on S. aureus and E. coli, respectively.

Familial resemblance in energy intake: contribution of genetic and environmental factors

Total energy intake and intakes of carbohydrate, fat, and protein as well as the percentage of energy derived from these nutrients were calculated from a 3-d dietary record in 1597 subjects living in 375 families of French descent. Familial correlations were computed in pairs of biological relatives and relatives by adoption and used in the path-analysis BETA model to determine the contribution of genetic and nongenetic factors in the familial resemblance observed in energy intake. No significant genetic effect was found for intake of any nutrient tested (h2 less than or equal to 11%) and cultural inheritance was found to be more important than genetic inheritance. Nontransmitted environmental factors, including home environmental effects, were found to account for more than 50% of the variation observed in the energy-intake components. These results suggest that the average genetic influence on nutrient intake is negligible and that nongenetic effects associated mainly with home environmental effects are the major affecters of energy intake.

Erythrocyte sedimentation rate in temporal arteritis

Some authors have reported that the erythrocyte sedimentation rate (ESR) is elevated in almost all patients with biopsy-proven temporal arteritis, while others believe it may be normal in up to 30% of such patients. We studied 62 patients with biopsy-proven temporal arteritis, and found that all of the 54 untreated patients and six of the eight treated patients had an elevated ESR; thus, when the ESR is normal, a diagnosis of temporal arteritis must be suspect.

Appraisal of modifiable hospitalization risks

Nine prevention experts rated hospitalization risks of 64 hypothetical healthy adults between 20 and 65 years old. There was substantial agreement among seven out of the nine experts. Pairwise correlations between any two of the experts ranged between 0.66 and 0.86. Decision analytic tools were used to model the average of the experts' ratings. The panel of experts provided us with the factors used, the relationship between the factors, and the relative importance of each factor. An index based on this information was highly correlated with the judgments of seven experts. Thus, we concluded that the scoring procedure can simulate the experts' judgments. Next, the index was used in an interactive computer program to assess modifiable health risks of individuals. This program is provided along with the paper to facilitate further research on validity and impact of the program.

The familial transmission of bipolar illness

As part of the National Institute of Mental Health Collaborative Program on the Psychobiology of Depression study, data were collected on 2225 first-degree relatives of 612 probands. We analyzed 187 families of bipolar patients (149 probands with a diagnosis of bipolar I disorder and 38 with a diagnosis of schizoaffective, manic subtype). Using traditional genetic methods, the morbid risk of bipolar illness in relatives was found to be 5.7% in the relatives of bipolar probands as contrasted with 1.1% in the relatives of probands with major depression. These values compared closely with those obtained using survival analysis. Relatives of probands with early onset were found to have a greater risk than relatives of probands with late onset. The sex of the relative, the sex of the proband, or the subtype of the proband (bipolar I or schizoaffective bipolar) did not influence the risk in the relative. The age at onset was found to be accelerated with birth cohort, with individuals born in more recent cohorts having an earlier onset. Multifactorial analysis found significant heterogeneity for sex-specific sibling correlations (with the brother-sister correlation smaller than the same-sexed correlations), and path analysis estimated transmissibility of liability to be 71%. The mixed model, which allows for a single major locus with a multifactorial background, gave evidence for the presence of a major locus when controlling for the effects of birth cohort and age at onset. However, this evidence is tempered when comparing the mixed model with a more general transmission model.