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PubMed1985

Factors predicting abnormal hysterosalpingographic findings in patients treated for acute pelvic inflammatory disease.

One hundred forty-six consecutive inpatients with acute pelvic inflammatory disease (PID) were randomly treated either with the combination of doxycycline and metronidazole or with the combination of penicillin G/amoxicillin and metronidazole. Forty-three women underwent hysterosalpingography (HSG) 6 months after the treatment, and a multivariate statistical analysis was used to study the effect of 11 different variables (parity, history of previous abortion, history of previous PID, use of an intrauterine contraceptive device (IUD), use of oral contraceptives, presence of adnexal mass, results of cervical cultures for Neisseria gonorrhoeae, and Chlamydia trachomatis, presence of serum antichlamydial antibodies, penicillin-metronidazole treatment, and doxycyclin-metronidazole treatment) on the hysterosalpingographic findings. Abnormal HSG was most likely to occur in women who had antichlamydial antibodies present in the serum, an adnexal mass detected on the initial bimanual examination, or had an IUD (positive associations) and least likely to occur in women who had been treated with the combination of doxycycline and metronidazole (negative association).

Acute Disease↗
PubMed1993

The relationship between ankle brachial index, other atherosclerotic disease, diabetes, smoking and mortality in older men and women.

The goal of this study is to investigate the relationship between peripheral arterial disease and mortality in a large patient population and assess the effects of other atherosclerotic diseases, diabetes and smoking on this relationship. All patients, 50 years or older and with no history of lower extremity surgery, evaluated for lower extremity arterial disease in a university hospital peripheral vascular laboratory over a 13-year period (1977-1989) were included in the study (n = 1930). Arterial disease was assessed by measurement of the resting ankle brachial index (ABI) in these patients. The ABI was calculated by dividing the systolic pressure in the tibial arteries by the pressure in the brachial artery. Analyses of the data by use of multivariate statistical techniques and by stratification of the patient population by co-morbid condition indicate that ABI is a robust and independent predictor of all-cause mortality in both men (relative risk (RR) = 1.6, 95% confidence interval (CI) 1.3, 2.0) and women (RR = 1.9, 95% CI 1.4, 2.4). The relative risks are essentially unchanged after exclusion of all patients with clinical history of cardiovascular disease or diabetes. Similarly, a low ABI is an important risk factor for mortality among patients with a history of stroke, angina or diabetes; men and women with a history of smoking and women who are non-smokers. Therefore, the measurement of ABI, a simple, objective, non-invasive technique which can be used in the physician's office, may be useful for early identification of patients at high risk for morbidity and mortality.

Aged↗
PubMed1994

Increased concentrations of neopterin in carotid atherosclerosis.

Activation of T-cells and macrophages may play a role in the pathogenesis of atherosclerosis. Therefore, serum concentrations of the immune activation markers neopterin and soluble interleukin-2 receptor were compared with routine laboratory parameters, candidate risk variables and degree of carotid atherosclerosis. Study subjects were 561 individuals (293 men and 268 women) aged between 50 and 79 years who were enrolled in a cross-sectional community based study (Ischemic Heart Disease and Stroke Prevention Study, Bruneck, Italy). Extent of carotid atherosclerosis was quantitated by an ultrasound B-mode procedure based scoring system. Detailed physical examination and quantification of laboratory and candidate risk variables were performed. By univariate as well as multivariate statistical analyses, serum concentrations of neopterin but not soluble interleukin-2 receptor were significantly higher in subjects with carotid atherosclerosis (men, 8.5 +/- 2.7 nmol/l neopterin; women, 9.6 +/- 3.3) than in those without (men, 6.7 +/- 2.3, P < 0.0001; women, 7.5 +/- 2.3, P < 0.0001). The data show that the macrophage-derived immune activation marker neopterin is closely correlated with the extent of carotid atherosclerosis. Chronic activation of immune cells, preferentially of macrophages, may play a key role in atherogenesis and/or progression of atherosclerosis.

Aged↗
PubMed1984

Three-dimensional reconstruction of the 30 S ribosomal subunit from randomly oriented particles.

Electron micrographs show the small (30 S) subunit of Escherichia coli ribosomes lying in a wide range of positions on the specimen support, related by rotation principally around the long axis of the particle. Through correspondence analysis, a multivariate statistical method that distinguishes the major factors accounting for interimage variance, the (aligned) views of the randomly oriented particles were ordered and grouped according to tilt angle. Views so grouped were then averaged and used as input to a three-dimensional reconstruction program. The particle reconstructed from nine averaged projections spanning a 160 degrees rotational range has a resolution of 5 nm in planes perpendicular to the long axis of the particle and approximately 3 nm in the direction of the long axis. It is somewhat asymmetrical and quite compact; its most conspicuous feature is the "platform" that wraps partially around the middle of the subunit.

Escherichia coli↗
PubMed1988

Three-dimensional structure of 50 S Escherichia coli ribosomal subunits depleted of proteins L7/L12.

A structural study of Escherichia coli 50 S ribosomal subunits depleted selectively of proteins L7/L12 and visualized by low-dose electron microscopy has been carried out by multivariate statistical analysis, classification schemes and the new reconstruction technique from single-exposure, random-conical tilt series. This approach has allowed us to solve the three-dimensional structure of the depleted 50 S subunits at a resolution of 3 nm-1. In addition, two distinct morphological populations of subunits (cores) have been identified in the electron micrographs analyzed and have been separately studied in three dimensions. Depleted subunits in the two morphological states present as main features common to these two structures but different from those of the non-depleted subunit (1) the absence of the stalk, (2) a rearrangement of the stalk-base that changes the overall structure of this region. This morphological change is quite noticeable and important, since this region is mapped as a part of the GTPase center. The two conformations differ mainly in the orientation of the area between the L1 region and the head (the probable localization of the peptidyl transferase center) and in the accessibility of the region located below the head. A possible relationship of these structural changes to the functional dynamics of the ribosome is suggested.

Escherichia coli↗
PubMed1981

Serum thyroid hormone abnormalities in psychiatric disease.

Psychiatric illness is a cause of "euthyroid sick syndrome" (ESS), defined as abnormal concentrations of circulating iodothyronines in euthyroid subjects with nonthyroidal illness (NTI). We describe a prospective study of 150 consecutive psychiatric admissions studied by endocrine and psychologic techniques. Based on 150 admission blood samples, we found a 7% incidence of ESS and with serial samples (74 patients) the incidence was 27%, demonstrating that ESS can develop after hospital admission. Of the 20 patients with ESS, 11 had elevation of both serum total T4 concentrations (T4) and free thyroxine index (FTI) while their serum total T3 concentrations (T3) remained normal; 5 had elevation of FTI without elevation of T4 or T3; and 4 had low T4 and low FTI and normal TSH. In 2 of the 4 patients in the last category, the T3 was also low. The free T3 index (FT3I) was normal in all but 1 patient who had low FT3I and FTI, low T4 and T3, and normal TSH. The serum thyroid hormone abnormalities were transient in the ESS patients during the 10 day period with 2 exceptions; 1 patient had persistently elevated T4 and FTI with normal T3 and FT3I values while another patient had persistently depressed T4 and FTI without abnormality of FT3I or TSH. Multivariate statistical analysis demonstrated a difference (P less than .06) in the psychologic attributes of somatic and autonomic symptoms in ESS patients compared to controls. We conclude that ESS is as common amongst psychiatric admissions as in general hospital patients previously studied and that blood thyroid function tests should be interpreted cautiously in all hospitalized patients.

Adolescent↗
PubMed1988

Induction of chromosome malsegregation by halogenated organic solvents in Aspergillus nidulans: unspecific or specific mechanism?

Three chloromethanes (dichloromethane, chloroform and carbon tetrachloride) and 8 chlorinated ethanes (1,1- and 1,2-dichloroethane, 1,1,1- and 1,1,2-trichloroethane, 1,1,1,2- and 1,1,2,2-tetrachloroethane, pentachloroethane and hexachloroethane) were assayed in tests for the induction of mitotic segregation in Aspergillus nidulans diploid strain P1. Eight of the 11 compounds assayed (dichloromethane, chloroform, carbon tetrachloride, 1,1- and 1,2-dichloroethane, 1,1,2-trichloroethane, 1,1,1,2- and 1,1,2,2-tetrachloroethane) significantly increased the frequency of morphologically abnormal colonies which produced euploid whole-chromosome segregants (haploids and non-disjunctional diploids). Only in one case (1,1,1,2-tetrachloroethane) was a borderline increase in crossing-over frequency observed, thus suggesting the involvement of non-DNA targets in aneuploidy induction by these chlorinated hydrocarbons. Conclusive evidence for the induction of aneuploidy as the primary genetic event was provided by experiments in haploid strain 35 with 1,2-dichloroethane and 1,1,1,2-tetrachloroethane. Mutagenic, lethal and growth-arresting activities were quantitatively estimated and compared to a series of descriptors of physical and chemical properties of the molecules by means of multivariate statistical analysis. Lipophilicity, known to be related to c-mitotic activity, did not show any significant relationship with aneuploidizing activity, whereas a possible correlation among physico-chemical descriptors and toxic properties of test chemicals was highlighted.

Aneuploidy↗
PubMed1992

Atmospheric deposition of trace elements around point sources and human health risk assessment. I: Impact zones near a source of lead emissions.

The deposition of lead was monitored over 8 years in the area around a car battery factory north of Copenhagen, Denmark. The area also has heavy traffic. Deposition was measured by in-situ grown vegetables, transplant grass culture biomonitors, bulk deposition and soil samples. Three impact zones were identified by a multivariate statistical analysis. Within each zone, the total dietary intake of lead was estimated for adults and children as a percentage of the provisional tolerably weekly intake (PTWI), and as a result recommendation on restrictions in use of locally grown fruit and vegetables were given to the public. The pattern of lead deposition in the area during the period 1981-1988 was monitored and the amount of lead ingested via vegetables was toxically evaluated. Lead emission reduction measures introduced in the factory and in the traffic during the period produced significant reductions in lead deposition.

Adolescent↗
PubMed1992

Atmospheric deposition of trace elements around point sources and human health risk assessment. II. Uptake of arsenic and chromium by vegetables grown near a wood preservation factory.

Kale, lettuce, carrots and potatoes were grown in 20 experimental plots surrounding a wood preservation factory, to investigate the amount and pathways for plant uptake of arsenic and chromium. Arsenate used in the wood preservation process is converted to the more toxic arsenite by incineration of waste wood and is emitted into the atmosphere. Elevated concentrations of inorganic arsenic and chromium were found both in the test plants and in the soil around the factory. Multivariate statistical analysis of the results indicated that the dominating pathway of arsenic and chromium from the factory to the leafy vegetables grown nearby was by direct atmospheric deposition, while arsenic in the root crops originated from both the soil and the atmosphere. Consumption of vegetables grown near the source would result in an increased intake of inorganic arsenic, but the intake via the total diet was estimated to be below the provisional tolerable daily intake for inorganic arsenic established by FAO/WHO.

Air Pollutants↗
PubMed1983

Prognostic factors in malignant epithelial ovarian tumors.

In a study of 494 patients with ovarian carcinoma all known factors that eventually influence prognosis were tested both separately and comparatively in a multivariate statistical analysis, using survival as the dependent variable. It was found that the histologic grade and the size of the residual tumor after surgery are the most important factors influencing survival. The histologic type affected prognosis only in Stage III patients with large residual tumors. The stage of tumor progression had prognostic value, although Stage IIa was found to have the same survival rate as Stage I of this disease. The state of the tumor capsules in Stage I had no prognostic effect. Ascites only affected survival in Stage III patients who had small or no residual tumor after surgery. Age was found to influence survival only in Stage III patients with small residual tumors, or no residual tumor, and in advanced Stage II cases. Continued chemotherapy seems to be of benefit in Stage III patients with small or no residual tumors following surgery.

Age Factors↗
PubMed1995

The relationship of the interval from breeding to uterine palpation for pregnancy diagnosis with calving outcomes in holstein cows.

This study used data collected prospectively at 32 dairy herds to examine the effect of interval from breeding to uterine palpation for pregnancy diagnosis on calving interval and likelihood of calving. Multivariable statistical models were used to control for other factors that were significantly associated with the outcomes of interest. Cows diagnosed pregnant from 30 to 36 d post breeding had 2-wk longer calving intervals than cows palpated at later intervals. The interval from breeding until a cow was diagnosed open had a significant positive association with the calving interval. The interval to palpation was not associated with the probability of remaining in the herd to calve when controlling for the effects of herd, season of freshening, number of services, days to first service and mature equivalent milk production. Among cows diagnosed pregnant, 3.4% subsequently were bred and 1.5% were diagnosed open by palpation at a later date. About 5% of the cows diagnosed open calved at a time consistent with being pregnant when the diagnosis was made.

Journal Article↗
PubMed1989

Quantitative morphological aspects of granulocytic differentiation induced in HL-60 cells by dimethylsulfoxide and retinoic acid.

HL-60 cells differentiate to mature granulocytes when cultured with DMSO or retinoic acid. These two drugs can induce different expression of phenotypic or functional properties in these cells. The morphological characteristics of the differentiation sequences elicited by these two drugs have been therefore evaluated by a quantitative cytological analysis technique using a SAMBA 200 cell image processor. The maturation sequences induced by DMSO or retinoic acid differed mainly in nuclear geometry and cytoplasmic granules expression. Multivariate statistical analyses of data reveal that DMSO and retinoic acid elicited granulocytic maturation through two separate morphological pathways which can be individualized as early as 24 hr after differentiation induction. Image processing may therefore offer an interesting tool for studying new drugs with differentiation potential in chemotherapy.

Analysis of Variance↗
PubMed1989

Investigation of multiple simultaneously active brain sources in the electroencephalogram.

We present a method of investigating multiple simultaneously active brain sources that overlap both in space and time in the scalp electroencephalogram (EEG). In order to identify the contributions of the individual brain sources to measured potentials, we applied principal component analysis and various methods of rotating the principal components including a newly developed rotation procedure using frequency criteria. We related the results of these multivariate statistical techniques to a new physical model using multiple current dipoles with fixed anatomical locations and time-varying activities. We thus are able to study 3-dimensional location, time activity and interaction of multiple simultaneously active brain sources in the scalp EEG.

Brain↗
PubMedDate not supplied

Schizo-affective disorders: bipolar-unipolar subtyping. Natural history variables: a discriminant analysis approach.

In view of tackling the problem of heterogeneity among the schizo-affectives, methods of univariate and multivariate statistical analysis (canonical discriminant analysis) were applied to the sociodemographic and natural history variables of four groups of affective disorder patients from the NIMH Collaborative Study on the Psychobiology of Depression Clinical section: the schizo-bipolar (SBP, n = 45), the schizo-unipolar (SUP, n = 30), the bipolar I (BP, n = 159) and the primary unipolar depressed (UP, n = 387) defined by Research Diagnostic Criteria. Two dimensions were identified among the four groups of 'affective' patients: the 'bipolar' and the 'schizophrenic' dimensions. They provided highly significant discrimination among the means of the four groups but were not very accurate in predicting group membership. The 'bipolar' dimension separates the UP from the BP and SBP, the SUP taking some intermediate value. The 'schizophrenic' dimension separates the BP and UP from the SUP, the SBP being intermediate. The two groups with the most similarities were the SBP and BP. The group with the most heterogeneity was the SUP, sharing similarities with the UP and SBP mostly. These conclusions are supported by results of familial aggregation on the same group of patients.

Bipolar Disorder↗
PubMed1991

FACTOREP: a new tool to explore the dimensions of depression.

One promising research approach in the search for clinically meaningful diagnostic categories of depression has been the application of multivariate statistical techniques such as factor analysis to the evaluation of self-report and observer rating data. The contribution of factor analysis has been limited, however, by the application of traditional mathematical criteria in the analyses which typically produce too many factors. In this study, a criterion of replicability was applied with the aid of a factor matching procedure (FACTOREP). The Beck Depression Inventory (BDI) was examined using FACTOREP and two large samples of depressed patients. The results showed that only a large general factor was present. Beyond the BDI studies, there has been debate on the validity of the endogenous versus reactive depression conceptualization. Despite the limited number of endogenous items in the BDI, the results here did not confirm the presence of two clear factors that represented endogenous and reactive groups of items.

Affective Disorders, Psychotic↗
PubMed1993

Heterogeneity in schizophrenia: an extended replication of the hebephrenic-like and paranoid-like subtypes.

Hebephrenic-like (H) and paranoid-like (P) subtypes of schizophrenia have previously been described by Farmer et al. (1983, 1984). The stability of this subtypology of schizophrenia was explored using multivariate statistical techniques on a large independent data set. Both a discriminant function analysis and an admixture analysis produced strong evidence for a bimodel distribution of scores consistent with the H-like and P-like subtypes.

Adult↗
PubMed1994

A multidimensional approach to analysis of cerebrospinal fluid biogenic amines in schizophrenia: I. Comparisons with healthy control subjects and neuroleptic-treated/unmedicated pairs analyses.

Recent hypotheses and findings indicate that measurements of interactions between cerebrospinal fluid (CSF) biogenic amine systems, rather than measurement of CSF biogenic amine metabolites, better correlate with clinically important findings in schizophrenia. To test hypotheses, we used a recent technological advance in high performance liquid chromatography with electrochemical detection and combined it with multivariate statistical analyses to study biogenic amine concentrations in CSF in schizophrenia. This approach enabled the study of the interactions of several metabolites of each of the three major neurotransmitter pathways (dopaminergic, noradrenergic, and serotonergic) to test existing hypotheses regarding the neurobiochemical basis of schizophrenia. Twenty biogenic amines, their metabolites, and other compounds from 24 medication-free schizophrenic patients and 12 normal control subjects were simultaneously measured using a recently developed technique of gradient high performance liquid chromatography coupled with a 16-channel electrochemical array detector. After covariation for storage time, results of a stepwise discriminant function analysis comparing the control and patient groups identified tryptophan, tryptophol, and epinephrine as discriminating variables. Hotelling's paired T2 test from a subgroup of schizophrenic patients studied while they were and were not receiving neuroleptic treatment did not yield any significant differences between subgroups. A discussion of the findings and a comparison with previous studies of CSF biogenic amines in schizophrenia are presented.

Adult↗
PubMed1992

Electron image analysis of ribosomal subunits from Thermus aquaticus.

Electron micrographs of ribosomal subunits from the thermophilic bacterium Thermus aquaticus were analysed using multivariate statistical analysis and characteristic views constructed to reproducible spatial resolutions ranging from 1.9 to 3.6 nm. These views were comparable to morphological classes of Escherichia coli ribosomal subunits, albeit with differences in fine features also found in archaebacterial ribosomes.

Bacterial Proteins↗