Self-monitoring and dating relationships.

Four investigations, with 479 university students, examined the involvement of self-monitoring propensities in dating relationships. Studies 1 and 2 examined willingness to change dating partners and form close, intimate dating relationships with other partners. Only Ss high in self-monitoring, as measured by the Self-Monitoring Scale, were willing to terminate current relationships in favor of alternative partners. In Study 3, for those involved in multiple dating relationships, high self-monitoring Ss reported having dated a greater number of partners in the preceding year than low self-monitoring Ss; for those in steady, exclusive dating relationships, low self-monitoring Ss reported having dated their current partner for considerably longer than high self-monitoring individuals. Study 4 examined growth of intimacy in dating relationships. The link between length of relationship and level of intimacy was more pronounced for low than high self-monitoring Ss. Findings suggest that high self-monitoring individuals adopt an "uncommitted" and low self-monitoring individuals a "committed" orientation toward dating relationships. Implications for understanding the evolution of intimate relationships, including marital ones, are discussed. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Receiver Performance for Heterodyne Optical Communication

A model for the heterodyne optical channel that is consistent with experimental observations is introduced, and a general maximum-likelihood sequence estimation receiver that accounts for laser phase instabilities is proposed using the generalized log-likelihood functional. The performance of various suboptimal "estimator-correlator" receivers, obtained from optimal, nonimplementable receiver equations, is studied by simulation and compared to that of an incoherent receiver for practical parameter values. It is observed that, for hard decisions, the proposed receiver performs significantly better than an incoherent receiver for bit intervals larger than about half the coherence time of the laser oscillators, with larger gains to be expected when soft decisions on long sequences are made. A way of reducing the complexity of the soft-decisions receiver for long sequences is discussed.     

AIDS: risk behaviors among rural Mexican women married to migrant workers in the United States

International migration between Mexico and the United States has been acknowledged as a phenomenon that may contribute to the spread of AIDS in rural Mexico. The purpose of this study is to identify the information held by the participants regarding AIDS and to describe selected high-risk behaviors for AIDS transmission among a representative sample of rural women living in Mexico who are married to immigrant temporary workers to the United States. The women who participated in the study were married, of reproductive age, and had active sex lives with their spouses. Results revealed that most of the women interviewed had at least some knowledge about AIDS. Although some misconceptions were evident, most of the information they had was accurate. About one-third of the women felt at risk for AIDS, mostly because they doubted their husbands' fidelity, or because in the last five years they had donated blood, received a blood transfusion, or received an intramuscular or intravenous injection. The results of the study are discussed within the sociocultural context that surrounds the lives of the women interviewed.     

Fibre couplers composed of unequal cores

To obtain the simplest results possible for couplers composed of nearly equal cores, terms of second order have been deliberately neglected in the previous conventional perturbation analysis. Merely by retaining these terms, we obtain the full perturbation results?results which satisfy power conservation exactly and which cannot be improved on within weak coupling. Our derivation shows that the recent `new thoery? of Hardy and Streifer, which necessitates consideration of radiation, is convoluted, unnecessary and contains fundamental errors.     

Pharmacokinetic characteristics and tolerability of a novel intravenous immunoglobulin preparation

Cathepsin D content and activity were determined in matched paired sets of colorectal tumor tissue and normal mucosa and correlated with a number of biological and clinical parameters. Significantly higher cathepsin D activity was measured in tumor cytosol compared to paired normal mucosa (p < 0.02), in Dukes' stage A tumors compared to Dukes' B and C (p < 0.05), in tumors < 5 cm compared to those > 5 cm, or in tumors with a low proliferation rate compared to those with a high proliferation rate (p < 0.05). Moreover, significant differences in enzyme activity between tumor tissue and paired normal mucosa were observed in node-positive and G2 tumors (p < 0.05). No significant correlation between cathepsin D activity and other biological parameters was found. Further, no differences in cathepsin D content between tumor tissue and paired normal mucosa were observed except in Dukes' stage A tumors (p < 0.02). A significantly increased cathepsin D content was also observed in tumors > 5 cm compared to tumors < 5 cm (p < 0.01). No relationship between tumor cathepsin D content and clinical stage was detected. However, a significant correlation (p < 0.05) was observed between the tumor-specific content of this enzyme and tumor grade. Finally, there was no relationship between tumor-specific cathepsin D activity and content (r = -0.27, p = 0.23). These data suggest that cathepsin D activity rather than content correlates with the malignant progression of colorectal cancer. This phenomenon should be taken into consideration when clinical studies are undertaken to assess the potential prognostic value of proteolytic enzymes involved in tumor progression.     

The genetic basis of epidermolysis bullosa simplex with mottled pigmentation

Epidermolysis bullosa simplex (EBS) is a group of autosomal dominant skin diseases characterized by blistering, due to mechanical stress-induced degeneration of basal epidermal cells. It is now well-established that the three major subtypes of EBS are genetic disorders of the basal epidermal keratins, keratin 5 (K5) and keratin 14 (K14). Here we show that a rare subtype, referred to as EBS with mottled pigmentation (MP), is also a disorder of these keratins. Affected members of two seemingly unrelated families with EBS-MP had a C to T point mutation in the second base position of codon 24 of one of two K5 alleles, leading to a Pro: Leu mutation. This mutation was not present in unaffected members nor in 100 alleles from normal individuals. Linkage analyses mapped the defect to this type II keratin gene (peak logarithm of odds score at phi = 0 of 3.9), which is located on chromosome 12q11-q13. This provides strong evidence that this mutation is responsible for the EBS-MP phenotype. Only conserved between K5 and K6, and not among any of the other type II keratins, Pro-24 is in the nonhelical head domain of K5, and only mildly perturbs the length of 10-nm keratin filaments assembled in vitro. However, this part of the K5 head domain is likely to protrude on the filament surface, perhaps leading to additional aberrations in intermediate filament architecture and/or in melanosome distribution that are seen ultrastructurally in patients with the mutation.     

The pathogenesis of gonococcal urethritis in men: confocal and immunoelectron microscopic analysis of urethral exudates from men infected with Neisseria gonorrhoeae

Confocal and immunoelectron microscopic analysis of urethral exudates from 12 men with gonococcal urethritis showed that Neisseria gonorrhoeae can invade urethral epithelial cells. Studies with acridine orange stain demonstrated that the majority of organisms within urethral epithelial cells were viable at the time of fixation. Three-dimensional modeling of an infected epithelial cell using image analysis of 21 digitized confocal sections stained with YOYO-1 and DiIC 18(3) revealed that gonococcal invasion of these cells occurred in a polar fashion, most likely at the epithelial luminal surface. Serial immunoelectron micrographs showed evidence of membrane fusion with pedestal formation between the gonococcus and the epithelial cell, gonococci within vacuoles, and occasional gonococci free in the cytoplasm. Immunoelectron microscopy studies showed ruptured vacuoles at the cell surface releasing organisms. These studies demonstrate that urethral epithelial cells are invaded by gonococci during the course of infection in males.     

Adenylyl cyclase activation underlies intracellular cyclic AMP accumulation, cyclic AMP transport, and extracellular adenosine accumulation evoked by beta-adrenergic receptor stimulation in mixed cultures of neurons and astrocytes derived from rat cerebral cortex

We have previously shown that stimulation of cortical cultures containing both neurons and astrocytes with the beta-adrenergic agonist isoproterenol (ISO) results in transport of cAMP from astrocytes followed by extracellular hydrolysis to adenosine [Rosenberg et al. J. Neurosci. 14 (1994) 2953-2965]. In this study we found that the endogenous catecholamines epinephrine (EPI) and norepinephrine (NE), but not dopamine, serotonin, or histamine, all at 10 microM, significantly stimulated intracellular cAMP accumulation, cAMP transport, and extracellular adenosine accumulation in cortical cultures. Detailed dose-response experiments were performed for NE and EPI, as well as ISO. For each catecholamine, the potencies in evoking intracellular cAMP accumulation, cAMP transport, and extracellular adenosine accumulation were similar. These data provide additional evidence that a single common mechanism, namely beta-adrenergic mediated activation of adenylyl cyclase, underlies intracellular cAMP accumulation, cAMP transport, and extracellular adenosine accumulation. It appears that regulation of extracellular adenosine levels via cAMP transport and extracellular hydrolysis to adenosine may be a final common pathway of neuromodulation in cerebral cortex for catecholamines, and, indeed, any substance whose receptors are coupled to adenylyl cyclase.     

Mitochondrial antigen/antibody systems in primary biliary cirrhosis: revisited

Methods for the evaluation of the four antimitochondrial antibody subtypes in primary biliary cirrhosis - anti-M2, -M4, -M8, -M9 - are described. The importance of the application of different preparations for the demonstration of complement fixing antibodies and the detection of antibodies by ELISA or Western blotting is emphasized. Complement fixing antigens can be prepared by discontinuous isopynic sucrose density gradient centrifugation using mitochondrial subfractions derived with from beef heart (M2), rat liver (M4), or pig kidney (M8). Anti-M9 antibodies do not fix complement. For ELISA, the pyruvate dehydrogenase or the ATPase-associated antigen fraction (M2), the sulfite oxidase fraction (M4), and the chromatographically purified M8-fraction should be used. The same antigen fractions are suitable for Western blotting, but anti-M4 and anti-M8 by ELISA and Western blotting a purified fraction prepared from rat liver has to be applied. Correlating antimitochondrial antibody-subtypes with clinical condition and the natural course, there is convincing evidence that especially the presence of complement fixing antibodies against the subtypes M2, M4, and M8 is a reliable indicator for a more active course. Patients expressing only anti-M9 (without anti-M2) have biochemically all the typical features also found in classical anti-M2 positive primary biliary cirrhosis patients, but seem not to advance to late stages. Since these antimitochondrial antibody-subtypes are present even in very early stages stages without changing their pattern during the course, antimitochondrial antibody-profiles can also be taken as early prognostic parameters. The evaluation of the immunological activity by antimitochondrial antibody-subtype testing may further facilitate the decision whether therapy with ursodeoxycholic acid should be combined with steroids and/or immunosuppressive agents. The role of mitochondrial autoantigens in the induction of this chronic destructive bile duct process is also discussed. The concept is put forward that not bile ducts but naive(?) B-cells expose the different mitochondrial antigens, thereby stimulating autoreactive T-cells to provide a second signal for antibody production. The degree of breakage of tolerance to the different mitochondrial epitopes may be one crucial factor which determines the diversity of antimitochondrial antibody-subtypes in patients with primary biliary cirrhosis.