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PubMedDate not supplied

Adoption versus parenting among young pregnant women.

Three groups of young pregnant women living in maternity residences--those who intended to place their babies for adoption, those who considered adoption but planned to parent and those who never considered adoption--were compared regarding their socioeconomic characteristics, attitudes toward adoption and the personal influences on their decisions. Of the 430 young women, those who intended to place their babies for adoption tended to be at one extreme on most profile variables, those who had considered placing were in an intermediate position, and those who never considered placing their babies were at the other extreme. Placers were both the most advantaged socioeconomically and held the most positive attitudes toward adoption, while young women who never considered adoption were the least advantaged and held the least favorable attitudes. Placers consistently reported that their choice to place their babies rather than parent would increase the likelihood of outcomes such as continuing with school, having enough money to live comfortably and benefiting the baby's emotional development, while those young women who did not consider adoption tended to feel that these outcomes would be more likely if they parented, or that the likelihood of the outcomes would not be affected by their choice. Young women who intended to place their babies were encouraged in that direction by their mothers, fathers and boyfriends, while the two groups of women who chose parenting were encouraged to do so by those in their social networks.

Adolescent↗
PubMed1990

[Castleman tumor, lichen ruber and pemphigus vulgaris: paraneoplastic association of immunological diseases?].

In a 45-year-old patient with an unusual clinical course of wide-spread cutaneous and oral lichen planus as well as pemphigus vulgaris of the oral cavity, both refractory to standard therapy, a Castleman tumour was suspected. Computer tomography disclosed a solid retroperitoneal tumour in the pelvis. After its surgical removal both dermatoses regressed substantially within a matter of weeks. In 1954 and again in 1956, Castleman described a thymoma-like lymph node hyperplasia, for which various synonyms are used. Castleman tumours are classified into the common hyalin-vascular type (80-90%), the rarer plasma cell type (10-20%) and the intermediate type. It is usually a benign lymphoma of variable location, but mostly intrathoracic. There is a remarkable association of Castleman tumours with skin diseases (lichen planus, pemphigus vulgaris, Kaposi sarcoma), neurological diseases (POEMS syndrome, myasthenia gravis, arteritis temporalis, Guillain-Barré syndrome), and internal diseases (nephrotic syndrome, amyloidosis, plasmacytoma, rheumatoid arthritis, thrombotic thrombocytopenic purpura). The coincidence of Castleman tumours with various immune phenomena and immunological diseases is higher than could be expected by chance, presenting a challenging pathophysiological model of antibodies and variable immunodeficiencies.

Castleman Disease↗
PubMed1990

Hydatidosis in Belgium: analysis of larval Echinococcus granulosus by SDS-PAGE and western blotting.

Echinococcosis/hydatidosis is characterized by the existence of various strains of the parasite Echinococcus granulosus. In order to study the degree of variability in Belgium, protoscoleces (PS) were isolated from infected intermediate hosts (horse, cattle, pig, goat and man). Homogenate supernatants of these PS were compared by SDS-polyacrylamide gel electrophoresis and western blotting: 15 to 26 predominantly silver staining bands (depending on the source of the parasites), were selected to study existing homologies among these possible strains. Antisera raised against PS homogenates of horse, cattle, pig and goat origin, were used to compare antigenicity by western blotting. The results indicate a closer similarity between E. granulosus of horse, goat and pig origin whereas E. granulosus derived from cattle showed less homology with any of the former. Results are discussed against the background of the occurrence of E. granulosus in Belgium.

Animals↗
PubMed1989

Significance and value of immunohistochemical localization of pregnancy specific proteins in feto-maternal tissue throughout pregnancy.

Tissue from 50 cases of products of conception and placenta at different gestational ages from as early as 12 d post ovulation up to 40 wk were examined by immunoperoxidase technique for localization of HCG, HPL, SP1, and PAPP-A. HCG was localized in the cytoplasm of syncytiotrophoblast (ST) with strong intensity in the 12-d blastocyst and remained strong until 8 to 10 wk. It then gradually decreased, becoming almost negative in term placenta. HCG was also seen in the cytoplasm of intermediate trophoblast (IT) at the implantation site but with variability in staining. HPL and SP1 appeared later than HCG in ST, and the intensity of staining increased rapidly to strongly positive by wk 8. They remained strong until full term. IT stained strongly positive with HPL throughout pregnancy, and some were different from the HCG positive ones. ST were constantly negative for PAPP-A throughout pregnancy. The latter, however, was definitely seen in the cytoplasm of cytotrophoblast (CT) of early blastocyst, the superficial epithelium of the endometrium adjacent to the implantation site, in many decidual cells around the implantation site and in the amniotic membrane epithelium.

Amnion↗
PubMed1978

Purification and substrate specificity of polymorphic forms of esterase D from human erythrocytes.

Esterase D (EsD), purified from human erythrocytes and tested with a variety of substrates, hydrolyzed only triacetin, tributyrin, and certain soluble aryl esters of aliphatic acids. Esters of 4-methylumbelliferone were easily the best substrates. When the three genetically different isozymes were compared, the less common forms, EsD 2 and EsD 2-1, were less stable than EsD 1. With some substrates, the Michaelis constant of the EsD 2 form differed from that of the EsD 1 form. The EsD 2-1 hybrid form was usually, but not invariably, intermediate in properties. The physiologic significance of the genetic variability of this enzyme is unknown.

Erythrocytes↗
PubMed1983

[Psychopathologic course dynamics as an indicator of variable psychotherapeutic-psychopharmacologic treatment strategies].

Psychotherapeutic endeavors of individuals in the context of a graduated overall psychotherapeutic and psychopharmacological strategy often fail to result in successful treatment because insufficient attention is paid to the biologically variable dimension of disturbed psychophysical integrity. The significance of intermediate pathogenetic stages in multistratified "neurotic" depressions and in anorexia nervosa and compulsive syndromes are dealt with in detail. Irrespective of the primary psychodynamics, neurobiologically modulated condition pictures with unusual autonomous dynamics can determine the picture. The same psychotherapy and somatotherapy does not entail the same action when carried out on a psychopathological substrate with different presentation and at different times. Finally, the possible transition from the psychosomatic clinical picture to "compensated" benzodiazepine-dependence is referred to. These secondary diseases exemplify iatrogenically modified psychopathological progress forms.

Anorexia Nervosa↗
PubMed1976

T and B cell patterns in irreversibly rejected human renal allografts. Correlation of morphology with surface markers and cytotoxic capacity of the isolated lymphoid infiltrates.

To define the composition and proliferative and functional activity of the rejection formed sheep erythrocyte rosettes (T cells), expressed surface Ig (B cells) or Fc receptors and specific lymphocyte-mediated cytotoxic activity. Small clumped lymphocytes (48.8 +/- 18.9 per cent) and plasma cells (18.8 +/- 10.9 per cent) were most common and correlated negatively (p less than 0.01). Percentages of surface Ig-bearing and small clumped lymphocytes correlated directly (p less than 0.05) as did the percentages of E rosette-forming and plasma cells (p less than 0.05). The percentages of surface Ig-bearing B cells correlated negatively with E rosette-forming T cells (p less than 0.05). Within this spectrum of rejection, three patterns could be identified. In the first pattern, humoral rejection (by immunofluorescence) was intense and cellular infiltration was primarily by surface Ig and Fc receptor-positive small clumped B lymphocytes. The second and most common pattern consisted of a mixed T and B cell infiltrate with intermediate to high lymphocyte-mediated cytotoxic activity and variable humoral rejection. In the third pattern, invitro studies showed primarily E rosette-forming T cells with paradoxically low lymphocyte-mediated cytotoxic activity. However, morphologic studies also revealed the highest percentages of plasma cells but only mild humoral rejection. Thus, combined morphologic and in vitro studies identified three patterns of protracted renal allograft rejection. Thus, combined morphologic and in vitro studies identified three patterns of protracted renal allograft rejection for which the percentages of plasma cells may provide a distinguishing morphologic marker. Furthermore, the degree of lymphocytic invasion of renal tubules and blood vessels may provide an estimate of lymphocyte-mediated cytotoxic activity.

Antibody Formation↗
PubMed1998

Angiographic evidence for the role of triglyceride-rich lipoproteins in progression of coronary artery disease.

Recent development in angiographic technology have enabled quantitative assessment of the effects of treatment on coronary arterial lesions. A meta-analysis of 12 angiographic studies showed that treatment to reduce low density lipoprotein (LDL) cholesterol levels decreases angiographic progression of coronary artery disease (CAD) by one-third, and increases the chance of lesion regression two-fold. However, these studies also show that the response to treatment to LDL cholesterol levels varies according to the severity of the coronary artery stenosis; lesions were seen to regress with treatment only if there was > 50% coronary artery stenosis at baseline. Other variables that have been implicated in CAD progression include intermediate density lipoprotein (IDL) non-high density lipoproteins (non-HDL) cholesterol and very low density lipoproteins (VLDL). Levels of IDL have been shown to decrease to a greater extent in patients whose lesions did not progress than in patients showing lesion progression. In untreated patients, an increase in non-HDL cholesterol was associated with an increase in risk of disease progression. In contrast, the most important predictor in treated patients was apo CIII (a marker of triglyceride-rich lipoprotein metabolism). Possible mechanistic links between triglyceride levels and CAD progression are discussed.

Apolipoprotein C-III↗
PubMed2001

DNA circle formation in Neisseria gonorrhoeae: a possible intermediate in diverse genomic recombination processes.

An important attribute that contributes to the virulence of Neisseria gonorrhoeae is its phenotypic variability, which is based on recombination within complex gene families in the genome. In this study we report on the in vivo amplification of large segments of the genome and the existence of circular DNA intermediates in the cell, which might help to explain the evolution of these gene families and provide possible clues as to how genetic variability is maintained. Using an inserted chromosomal marker (cat) in the N. gonorrhoeae MS11 genome that confers low-level resistance to chloramphenicol (Cm), we isolated variants that express resistance to high levels of Cm. Genetic analysis revealed that virtually all variants harboured single or multiple tandem amplifications of the respective genome segments carrying the cat insert. This process occurred independently of both the location of the cat insertion site and of the presence of a functional recA gene. Analysis of the genetically well characterised pilC region revealed a head-to-tail orientation of the amplified segments, with the junctions being located within direct repeats. Identical junctions were detected in extra-chromosomal circular DNA molecules isolated from non-selected wild-type and recA strains, suggesting that both types of structure arise by related processes. The existence of DNA circles was shown by their banding behaviour in caesium chloride/ethidium bromide density centrifugation and their resistance to digestion by exonuclease. The possible roles of such circles in processes such as pilin gene recombination, chromosomal gene amplification and genetic transformation are discussed.

Blotting, Southern↗
PubMed1999

Differences between bacterial species shown by simultaneous assessment of neutrophil phagocytosis and generation of reactive oxygen intermediates in trauma patients.

HYPOTHESIS: Previous studies on alterations in phagocytosis and bacterial killing after trauma have yielded conflicting results. We hypothesize that these changes are variable, depending on the species of bacteria used to assay these variables. DESIGN: Blood samples from patients were assayed by means of flow cytometry for phagocytosis and reactive oxygen intermediate generation. Several common clinical pathogens were used: Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. Results were compared with those from controls. SETTING: Regional level I trauma center. PATIENTS: Ten consecutive patients were studied with E. coli and K. pneumoniae. Five of these were also studied with S. aureus. Patients were 18 years of age or older, with an Injury Severity Score of 16 or more. Patients who were taking corticosteroids before hospital admission or who were administered corticosteroids before blood was drawn were not studied. Isolated head injuries or limb fractures were also excluded. Controls consisted of healthy volunteers. MAIN OUTCOME MEASURES: The ingestion of bacteria by neutrophils and the generation of reactive oxygen intermediates. RESULTS: After trauma, phagocytosis of E. coli was enhanced, whereas ingestion of K. pneumoniae was depressed. Ingestion of S aureus remained unchanged. The generation of reactive oxygen intermediates was depressed after incubation with E. coli and unchanged with K. pneumoniae, but enhanced with S. aureus. CONCLUSIONS: Neutrophil response to trauma is dependent on which bacterial species the cell is attempting to kill. This may, in part, explain why only a limited number of bacterial species cause a significant proportion of early infections after trauma.

Adolescent↗
PubMed2004

Inheritance of most X-linked traits is not dominant or recessive, just X-linked.

The existence of X-linked disorders in humans has been recognized for many centuries, based on lessons in religious texts and observations of specific human families (e.g., color blindness or Daltonism). Our modern concepts of Mendelian (including X-linked) inheritance originated just after the turn of the last century. Early concepts of dominance and recessiveness were first used in conjunction with autosomal traits, and then applied to "sex"-linked traits to distinguish X-linked recessive and X-linked dominant inheritance. The former was defined as vertical transmission in which carrier women pass the disorder to affected sons, while the latter was defined as vertical transmission in which daughters of affected males are always affected, transmitting the disorder to offspring of both sexes. However, many X-linked disorders such as adrenoleukodystrophy, fragile X syndrome, and ornithine transcarbamylase deficiency do not fit these rules. We reviewed the literature on 32 X-linked disorders and recorded information on penetrance and expressivity in both sexes. As expected, penetrance and an index of severity of the phenotype (defined in our Methods) were both high in males, while the severity index was low in females. Contrary to standard presentations of X-linked inheritance, penetrance was highly variable in females. Our analysis classified penetrance as high in 28% of the disorders studied, intermediate in 31%, and low in 40%. The high proportion of X-linked disorders with intermediate penetrance is difficult to reconcile with standard definitions of X-linked recessive and dominant inheritance. They do not capture the extraordinarily variable expressivity of X-linked disorders or take into account the multiple mechanisms that can result in disease expression in females, which include cell autonomous expression, skewed X-inactivation, clonal expansion, and somatic mosaicism. We recommend that use of the terms X-linked recessive and dominant be discontinued, and that all such disorders be simply described as following "X-linked" inheritance.

Chromosomes, Human, X↗
PubMed2005

The percentage of positive biopsy cores as a predictor of disease recurrence in patients with prostate cancer treated with radical prostatectomy.

OBJECTIVE: To analyse the prognostic value of the percentage of positive biopsy cores (PPBC) in determining the pathological features and biochemical outcome of patients with prostate cancer treated by radical prostatectomy, as published data evaluating the prognostic value of PPBC in such patients have limitations. PATIENTS AND METHODS: A group of 534 patients with clinically localized prostate cancer was selected. The PPBC was defined as the number of positive biopsy cores/total number of biopsy cores x 100, and grouped into categories of <25%, 25.1-50%, 50.1-75% and 75.1-100%. Patients were divided in low-, intermediate- and high-risk groups according to the usual variables. RESULTS: The mean follow-up was 60.5 months. PPBC was associated with the preoperative serum prostate-specific antigen (PSA) level, biopsy Gleason score and clinical stage. On multivariate analysis, PPBC was a significant predictor of extraprostatic disease and seminal vesicle involvement. Of patients in the four PPBC categories, 16%, 27%, 33% and 60%, respectively, had biochemical recurrence (P < 0.001), and on Cox regression analysis, PPBC was an independent predictor of disease recurrence. After segregating patients into risk groups the PPBC further stratified patients using thresholds of 75% (P = 0.006), 25% (P = 0.026) and 50% (P = 0.011) for low-, intermediate- and high-risk groups, respectively. CONCLUSIONS: We confirmed, with a longer follow-up, the clinical utility of the PPBC in determining the pathological features and biochemical outcome of patients with prostate cancer treated with radical prostatectomy, and established thresholds for use in patients in the three risk groups.

Adult↗
PubMed1990

[Coronary insufficiency caused by atherosclerosis. Current pathogenic concepts, clinical, angio-anatomic correlations and therapeutic deductions].

The multiplicity of clinical expressions of coronary artery failure results from the interaction between three processes which varies from one patient to another and from one time to another in a given patient. The three processes involved are: atheromatous coronary stenosis, arterial spasm and the development of a fibrino-thrombocytic thrombus. In stable angina pectoris, atheromatous narrowing, with smooth, regular outlines, no endothelial injury and little likelihood of complication by thrombosis predominates. In contrast, labile angina and myocardial infarction give rise to the same lesions: usually irregular stenoses, with a narrow neck and irregular outline. They correspond histologically to the rupture of an atheroma plaque, frequently complicated by the appearance in situ of a clot. In the authors' experience, complete arterial occlusion ensues in three out of four cases. The rate at which aggravation progresses and the variable degree of collateral circulation explains why a whole range of intermediate clinical expressions are possible, ranging from labile angina to sudden death of ischemic origin, and including various forms of infarction (both with and without the Q wave). Healing of these lesions may also be observed, usually resulting in progression of the coronary stenosis and sometimes of modification of left ventricular function of variable duration (myocardial stunning or hibernation). The importance of thrombotic phenomena in triggering the most serious forms of coronary artery failure (labile angina and myocardial infarction) provides a more precise identification of the place of thrombolytic treatment. In addition, it appears that there is no point in emergency revascularization of the ischemic myocardium. However, despite recent clinical progress, coronary artery disease remains a worrying illness which calls for primary prevention measures. Such measures must be undertaken as soon as possible if they are to be effective.

Angina Pectoris↗
PubMed1995

Conformational variability in the refined structure of the chaperonin GroEL at 2.8 A resolution.

Improved refinement of the crystal structure of GroEL from Escherichia coli has resulted in a complete atomic model for the first 524 residues. A new torsion-angle dynamics method and non-crystallographic symmetry restraints were used in the refinement. The model indicates that conformational variability exists due to rigid-body movements between the apical and intermediate domains of GroEL, resulting in deviations from strict seven-fold symmetry. The regions of the protein involved in polypeptide and GroES binding show unusually high B factors; these values may indicate mobility or discrete disorder. The variability of these regions may play a role in the ability of GroEL to bind a wide variety of substrates.

Bacterial Proteins↗
PubMed2006

Reactive intermediates and the pathogenesis of adverse drug reactions: the toxicology perspective.

Severe adverse drug responses are infrequent but occasionally serious events that are not readily predictable at the preclinical development level using only non-human or in vitro models. A common characteristic of the more serious toxicities is generation of short-lived and highly reactive electrophilic species in some individuals. The objective here is to review the literature for toxicological mechanisms that underlie known adverse drug reactions and then categorize the biological consequences of reactive chemical intermediates and radicals in terms of human risk factors and known metabolic variables. Xenobiotics described as being associated with rare but potentially serious adverse events affecting liver, skin, or causing blood dyscrasias tend to have three of four essential characteristics, (1) they are capable of forming short-lived reactive intermediates (RI) or free radicals in target tissues under ideal conditions that are distinct from primary metabolic products, (2) these RI escape/overwhelm the detoxification mechanisms associated with the site of origin or form toxic conjugates, (3) the unconjugated RI must either selectively damage critical proteins or other key macromolecules or (4) the RI acts as a hapten and stimulates an immunological (hypersensitivity) response or overcomes tolerance. Some risk factors may increase the probability of susceptibility, but this remains an active area of research. Because of the complexity of the pathogenesis of some injuries and the role of individual factors, no highly predictive in vitro screening methods are available; however, several methods are evolving that may be used to reveal mechanisms of action when a serious adverse effect is encountered.

Animals↗
PubMed1969

Choice and rate of reinforcement.

Pigeons' responses in the presence of two concurrently available (initial-link) stimuli produced one of two different (terminal-link) stimuli. The rate of reinforcement in the presence of one terminal-link stimulus was three times that of the other. Three different pairs of identical but independent variable-interval schedules controlled entry into the terminal links. When the intermediate pair was in effect, the pigeons distributed their (choice) responses in the presence of the concurrently available stimuli of the initial links in the same proportion as reinforcements were distributed in the mutually exclusive terminal links. This finding was consistent with those of earlier studies. When either the pair of larger or smaller variable-interval schedules was in effect, however, proportions of choice responses did not match proportions of reinforcements. In addition, matching was not obtained when entry into the terminal links was controlled by unequal variable-interval schedules. A formulation consistent with extant data states that choice behavior is dependent upon the amount of reduction in the expected time to primary reinforcement, as signified by entry into one terminal link, relative to the amount of reduction in expected time to reinforcement signified by entry into the other terminal link.

Journal Article↗
PubMed1981

The occurrence and identification of alpha-thalassemia-2 among hemoglobin S heterozygotes.

The in-vitro synthesis of hemoglobin (Hb) chains was studied among 60 Hb S heterozygotes (AS) having different quantities of Hb S, including five with an associated alpha-chain heterozygosity (ASAG). Hematologic values and hemoglobin composition were studied in these cases and in 15 other ASAG heterozygotes. The percentages of Hb S (which fell between 27% and 42%) and the mean corpuscular volume values correlated directly with the alpha/non-alpha values, confirming previous suggestions (Huisman, Hemoglobin 1:349, 1977) that the concomitant occurrence of an alpha-thalassemia-2 heterozygosity (alpha alpha(0)/alpha alpha; beta/beta(S)) or homozygosity (alpha(0) alpha/alpha(0) alpha; beta/beta(S)) resulted in intermediate or lower levels of Hb S compared with Hb S heterozygotes having four active alpha-chain genes (alpha alpha/alpha alpha; beta/beta(S)). Among ASAG heterozygotes, the occurrence of low (about 25%), intermediate (about 33%), or high (about 45%) proportions of an alpha-chain variant resulting from a variability in the number of active alpha-chain genes due to alpha-thal-2 coincided with high (39%), intermediate (34%), or low (28%) levels of Hb S, respectively. However, the overlap of biosynthetic data between Hb S heterozygotes with four, three, or two active alpha-chain genes prevents a reliable diagnosis in individual cases.

Anemia, Sickle Cell↗
PubMed1997

Influence of abdominal aortic aneurysm size on the feasibility of endovascular repair.

PURPOSE: To assess the effect of abdominal aortic aneurysm (AAA) size on overall aneurysm morphology with special attention to possible relationships among various anatomic variables that determine the feasibility of endovascular repair. METHODS: One hundred sixty-eight patients were assessed with spiral computed tomographic angiography to measure the length and diameter of the AAA, the proximal neck, and the common iliac arteries. Anatomic variables were correlated with aneurysm size using Spearman's rank order correlation coefficients (rS); comparisons among small, intermediate, and large aneurysms were made using the Chi-square test. RESULTS: Correlations between aneurysm size and the anatomic variables above were weak. The strongest association was between aneurysm size and aortic length (rS = 0.41, p < 0.001). Subgroup analysis showed no difference in proximal neck length, neck diameter, or overall suitability for endovascular repair between aneurysms greater or smaller than 5.5-cm diameter. However, significantly more short (< 1.5 cm), wide (> 3 cm), and hence, unsuitable proximal necks were found in patients with aneurysms > 7 cm in diameter (chi 2 = 7.8, p < 0.01). CONCLUSIONS: Shortening and widening of the proximal neck seems to increase with aneurysm size but only after the aneurysm expands beyond 7 cm in diameter. Aneurysms with diameters in the 4.5- to 5.5-cm range are no more suitable for endovascular repair than those between 5.5 and 7 cm. The lack of any significant correlation between anatomic variables emphasizes the need for accurate preoperative assessment of the anatomy of each individual patient before endovascular repair.

Aorta, Abdominal↗