Filarial nematode parasites secrete a homologue of the human cytokine macrophage migration inhibitory factor

Filarial nematode parasites establish long-term chronic infections in the context of an antiparasite immunity that is strongly biased toward a Th2 response. The mechanisms that lead to this Th2 bias toward filarial antigens are not clear, but one possibility is that the parasites produce molecules that have the capacity to proactively modify their immunological environment. Here we report that filarial parasites of humans secrete a homologue of the human proinflammatory cytokine macrophage migration inhibitory factor (MIF) that has the capability of modifying the activity of human monocytes/macrophages. A cDNA clone isolated from a Brugia malayi infective-stage larva expression library encoded a 12.5-kDa protein product (Bm-MIF) with 42% identity to human and murine MIF. MIF homologues were also found to be expressed in the related filarial species Wuchereria bancrofti and Onchocerca volvulus. Bm-mif was transcribed by adult and larval parasites, and the protein product was found in somatic extracts and in the parasite's excretory-secretory products. Immunohistocytochemistry revealed that Bm-MIF was localized to cells of the hypodermis/lateral chord, the uterine wall, and larvae developing in utero. Unexpectedly, the activities of recombinant Bm-MIF and human MIF on human monocytes/macrophages were found to be similar. When placed with monocytes/macrophages in a cell migration assay, Bm-MIF inhibited random migration. When placed away from cells, Bm-MIF induced an increase in monocyte/macrophage migration that was specifically inhibited by neutralizing anti-Bm-MIF antibodies. Bm-MIF is the first demonstration that helminth parasites produce cytokine homologues that have the potential to modify host immune responses to promote parasite survival.

Lack of DNase I mRNA sequences in murine lenses

Clarity of the mammalian lens is due in part to the complete lack of internal organelles, including nuclei, within the lens fiber cells that compose the bulk of the lens. Experimental evidence shows that as the differentiation of lens fiber cells progresses, nuclei and nuclear DNA are actively degraded. Prior characterization of chick lens development suggests that DNase I could be involved in lens DNA degredation. However, recent data suggest that DNase I is unlikely to be the nuclease responsible for DNA degredation in the differentiating lens. In this report, we find that in the murine lens, mRNA for DNase I is undetectable by northern blotting or PCR. We conclude that mRNA for DNase I is either not present or present in very low levels in murine lens. Our results are consistent with the hypothesis that DNase I is not involved in lens DNA degredation.

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Stress experienced by physicians and nurses in the cancer ward

This study examined occupational stress amongst medical staff on cancer wards. The sample consisted of 91 nurses and 57 physicians from 13 institutions in Bavaria, F.R.G. Strong associations emerged between specific, situational stressors and reported psychosomatic complaints. In particular, interpersonal difficulties, whether on or off the job, related to physical distress amongst nurses. For doctors, dissatifaction with the job and working conditions related to general malaise. Certain characteristics of the carer (sex, profession, age) and of the institutional environment (e.g. presence of trainees, size of institution) were also linked with stress and complaint levels.

Effects of cyclosporine and cortisone on the pathogenesis of primary infection with cytomegalovirus in the guinea pig

Effects of the immunosuppressive agents cyclosporine (CsA) and cortisone on the pathogenesis of primary infections with cytomegalovirus (CMV) were investigated in the guinea pig model. All animals received 10(4) 50% tissue culture infectious doses of virulent salivary gland-passaged guinea pig CMV (GPCMV) subcutaneously on day 0. Oral CsA (20 mg/kg per day) and/or subcutaneous cortisone (10 mg/kg per day) were administered until the animals were killed on day 14. Untreated controls developed lymphocytosis, and GPCMV was isolated from 19.4% of cocultivated tissues. Animals treated with CsA alone developed lymphopenia, and GPCMV was isolated from 53% of their tissues, including 16 of 16 lungs. Histopathology showed widespread viral inclusions and minimal inflammatory response to GPCMV in CsA-treated animals. Guinea pigs treated with either cortisone or CsA/cortisone did not develop lymphopenia, and their rates of isolation of GPCMV were significantly lower than those of CsA-treated animals.

The Cognitive Failures Questionnaire (CFQ) and its correlates

This paper describes a questionnaire measure of self-reported failures in perception, memory, and motor function. Responses to all questions tend to be positively correlated, and the whole questionnaire correlates with other recent measures of self-reported deficit in memory, absent-mindedness, or slips of action. The questionnaire is however only weakly correlated with indices of social desirability set or of neuroticism. It is significantly correlated with ratings of the respondent by his or her spouse, and accordingly does have some external significance rather than purely private opinion of the self. The score is reasonably stable over long periods, to about the same extent as traditional measures of trait rather than state. Furthermore, it has not thus far been found to change in persons exposed to life-stresses. However, it does frequently correlate with the number of current psychiatric symptoms reported by the same person on the MHQ; and in one study it has been found that CFQ predicts subsequent MHQ in persons who work at a stressful job in the interval. It does not do so in those who work in a less stressful environment. The most plausible view is that cognitive failure makes a person vulnerable to showing bad effects of stress, rather than itself resulting from stress.

The Cognitive Failures Questionnaire (CFQ) and its correlates

This paper describes a questionnaire measure of self-reported failures in perception, memory, and motor function. Responses to all questions tend to be positively correlated, and the whole questionnaire correlates with other recent measures of self-reported deficit in memory, absent-mindedness, or slips of action. The questionnaire is however only weakly correlated with indices of social desirability set or of neuroticism. It is significantly correlated with ratings of the respondent by his or her spouse, and accordingly does have some external significance rather than purely private opinion of the self. The score is reasonably stable over long periods, to about the same extent as traditional measures of trait rather than state. Furthermore, it has not thus far been found to change in persons exposed to life-stresses. However, it does frequently correlate with the number of current psychiatric symptoms reported by the same person on the MHQ; and in one study it has been found that CFQ predicts subsequent MHQ in persons who work at a stressful job in the interval. It does not do so in those who work in a less stressful environment. The most plausible view is that cognitive failure makes a person vulnerable to showing bad effects of stress, rather than itself resulting from stress.