Interferon-gamma induced proliferation of human myeloid leukaemia cell lines

Interferon-gamma (IFN-γ) is a pleiotropic cytokine involved in the regulation of various phases of immune and inflammatory responses; it also has anti-viral and anti-proliferative activity. Using continuous human leukaemia cell lines as model systems, we found that IFN-γ stimulated the proliferation of leukaemic myeloid cells; this effect was specifically neutralized by an anti-IFN-γ monoclonal antibody (McAb). No proliferative response was seen in autonomously growing cell lines; however, 11/19 constitutively growth factor-dependent cell lines showed a significant response in short-term proliferation assays upon incubation with IFN-γ. The stimulation indices ranged from 2 to 37 compared with the untreated control cells; the EC50 values for these cell lines were in the range of 0.1–0.6 ng/ml IFN-γ. Flow cytometric analysis demonstrated heterogeneity in the expression of the IFN-γ receptor, as it was found on 37–97% of the cells per cell line. The effects of IFN-γ on proliferation triggered by a spectrum of 10 other cytokines were variable, and both stimulation and attenuation of the proliferative responses were seen in different cell lines. Under serum-free culture conditions, IFN-γ acted as a survival factor suppressing apoptosis. As has been described for other functional processes triggered by IFN-γ, the proliferation-inducing activity of IFN-γ also led to activation of the signal transducing element STAT 1. Thus, IFN-γ can induce myeloid leukaemia cells to proliferate and can modulate their proliferative response to other cytokines. Therefore IFN-γ may be a pathologically relevant ligand for leukaemic cell proliferation in vivo . In physiological settings, IFN-γ might be a bifunctional regulator of haemopoietic cell proliferation, depending on other differential co-signals from the micro-environment.     

Mixed median nerve forearm conduction velocity in the presence of focal compression neuropathy at the wrist versus peripheral neuropathy

OBJECTIVES: To establish normal values for the conduction velocity of the mixed median nerve in the forearm, and to determine the use of mixed median nerve conduction velocity (NCV) studies across the forearm in the differential diagnosis of carpal tunnel syndrome (CTS), peripheral neuropathy, and CTS with peripheral neuropathy. DESIGN: Criterion standard. Mixed median NCV studies across the forearm were added to routine CTS investigational protocols. SETTING: University outpatient setting, rural referral base. PARTICIPANTS: Thirty healthy volunteers and 60 patients referred with symptoms and signs suggestive of CTS and/or peripheral neuropathy. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Motor sensory and mixed median nerve conduction velocity across the forearm. RESULTS: The mean mixed median NCV across the forearm was 64.5 m/s in healthy subjects and subjects with CTS. The mean mixed NCV in subjects with peripheral neuropathy was 54 m/s, even in the presence of CTS. CONCLUSION: Mixed median NCV in the forearm added to the standard protocols is helpful in differentiating the diagnosis of CTS from peripheral neuropathy and CTS with peripheral neuropathy.     

Infertility and early parent–infant interactions

Approximately 50% of infertile couples will become parents through pregnancy or adoption, but they experience major difficulties while working towards this goal. Infertility treatments are associated with physical pain and psychological distress, and adoption procedures are prolonged and emotionally stressful. The extent to which these stressors alter the parenting of these couples is not known. The purpose of this study, therefore, was to examine the early parent–infant interactions in infertile couples who become parents through pregnancy or adoption. Two groups of infertile couples (30 who achieved pregnancy and 21 who adopted) and a group of 19 couples without fertility problems were observed interacting with their infants twice, 7 to 21 days after the infant's arrival and a week later, at a time when both parents were at home. Their babies were between 9 days and 5 months of age. Behaviours of the mother, father and infant were recorded every 10 seconds, beginning when the baby was picked up and ending when the baby was put down asleep or 1½ hours had passed. Repeated measures ANOVAs were used to compare the three groups over the observations. There were no differences between fertile and infertile biological parents. Adopted infants showed more alertness, less sleeping, more smiles, and more looking than biological infants. Adoptive mothers spent less time as the sole interactor. Adoptive parents spent more time in playing with their infants and held and touched them less than did biological parents. Infertility, therefore, does not appear to affect early parenting. In general, the amounts of behaviours exhibited by infertile biological parents were very close to those of fertile parents. Differences in the behaviours of adoptive as compared to biological parents can best be explained as responses to the behaviours of their older infants, rather than as evidence of different parenting styles.     

Exploring the gender-technology relation in nursing

Exploring the gender-technology relation in nursing
Feminist and nursing scholars have emphasized the critical role Western technology has played in the history and development of women and nursing. Yet, despite their common ground in tying both the emancipation and the subordination of women and nurses to technology, there has been virtually no association between nursing and gender-technology studies. Gender-technology studies offer nursing scholars new analytic directions and methodological tools to explore the nursing-technology relation. Nursing, in turn, offers gender-technology studies a rich empirical site to further its theoretical development.     

Database analysis of injury patterns in an institution for developmental disabilities

This paper reports the results of a statistical analysis of injuries to the clients and the employees of a state facility for people with developmental disabilities, as recorded in the respective databases of the institution. The goal of the analysis was to identify the characteristics and patterns of injuries in order to identify priorities for technological intervention. Databases for 2000 client injuries and for 900 direct care staff injuries between 1988 and 1991 were analyzed retrospectively. Most of the injuries were sustained by the direct care staff and involved their backs. The injuries occurred in the institution's bedrooms (approximately 25%) and bathrooms (approximately 15%) and took place mainly during the early morning (approximately 30%) and evening rush (20%). The time of day and location of the injuries of clients coincided with those of the injuries of employees. These findings direct the focus of technological based interventions.     

Imaging early practice effects in arithmetic

A better understanding of learning processes in arithmetic in healthy adults can guide research into learning disabilities such as dyscalculia. The goal of the present functional magnetic resonance imaging study was to investigate the ongoing process of learning itself. No training was provided prior to the scanning session. Training consisted in a higher frequency of repetition for one set of complex multiplication problems (repeated) and a lower frequency for the other set (novel). Repeated and novel problems were presented randomly in an event-related design. We observed activation decreases due to training in fronto-parietal areas and the caudate nucleus, and activation increases in temporo-parietal regions such as the left angular gyrus. Training effects became significant after approximately eight repetitions of a problem and remained stable over the course of the experiment. The change in brain activation patterns observed was similar to the results of previous neuroimaging studies investigating training effects in arithmetic after a week of extensive training. The paradigm employed seems to be a suitably sensitive tool to investigate and compare learning processes on group level for different populations. Furthermore, on a more general level, the early and robust changes in brain activation in healthy adults observed here indicate that repeating stimuli can profoundly and quickly affect fMRI results.     

Effects of acute stress on the day of proestrus on sexual behavior and ovulation in female rats: participation of the angiotensinergic system

Physical or emotional stress can affect the female reproductive physiology and angiotensin II (Ang II) is a hormone that participates in the stress response and also in the control of reproductive hormones. The present study aimed at evaluating the effects of acute stress in the morning and afternoon of proestrus on sexual behavior and ovulation and the participation of Ang II in the stress-induced effects. Female rats with regular estrous cycles were used. Several different stress protocols were tested in the morning and in the afternoon of proestrus: restraint stress 10 min; restraint stress 1 h and ether stress, respectively. The participation of Ang II was evaluated by injecting Ang II receptor antagonists (losartan and PD123319) 15 min before stress. The lordosis quotient was recorded and the number of oocytes was counted. Plasma levels of luteinizing hormone, progesterone, prolactin and corticosterone were measured. All types of stress in the morning of proestrus induced a reduction in the number of oocytes. Restraint stress (1 h) in the afternoon of proestrus induced a significant reduction in the lordosis quotient. Peripheral and central losartan, but not PD123319, injections partly reverted the effects of stress on ovulation in the morning of proestrus. Acute stress in the morning of proestrus also reduced luteinizing hormone, progesterone and prolactin surges later on the same day. In conclusion, acute stress on the day of proestrus can affect female reproductive physiology. Moreover, the angiotensinergic system, through AT(1) receptors, participates in the effects of acute stress in the morning of proestrus.