Motivation and continuation of professional development.

Variations in levels of motivation to learn among established general practitioners (GPs) have received scant attention. Building on previous work, we present an analysis of factors contributing to the development of motivation to learn in those who are entering and already established in practice. This approach suggests that individual motivation is both complex and unstable in response to external factors. We draw attention to the possibility of motivational immaturity in recruits to general practice, the contribution of values, and the presence of demotivators. The implications of our analysis are explored in relation to individual professional development and continuing education provision. We suggest that motivational audit will identify individual and contextual factors that are reducing the capacity of GPs to continue learning. A number of approaches addressing these factors are proposed.     

Neutrophils play a critical role in early resistance to amebic liver abscesses in severe combined immunodeficient mice.

Animal models of liver abscess formation with Entamoeba histolytica suggest that the neutrophil is the first cell of the host immune system to interact with the invading ameba. In vitro studies have suggested that lysis of neutrophils by virulent amebae may exacerbate the damage seen in amebic liver abscesses. To investigate the role of neutrophils in vivo, we used the severe combined immunodeficient (SCID) mouse model of amebic liver abscess formation and compared liver damage in neutrophil-depleted and control mice. We found that neutrophil-depleted animals have significantly larger amebic liver abscesses at early stages of infection and that abscesses in neutrophil-depleted SCID mice lack the prominent inflammatory cell ring seen in amebic liver abscesses in control SCID mice. These data suggest that neutrophils play a protective role in the early host response to amebic infection of the liver.     

Prospective strategies for cholinergic interventions in Alzheimer's disease

The cholinergic hypothesis of memory dysfunction has guided most of the recent proposals for treating the primary symptoms of AD. The efficacy of these treatments has been severely limited. This review examines two major lines of evidence which suggest that the cholinergic hypothesis may have to be expanded and revised. The cholinergic hypothesis focuses on pre-synaptic defects. It assumes cholinoceptive neurons would function normally with adequate stimulation. Evidence is not sufficient to support this assumption. In addition, dissociations have been demonstrated between muscarinic receptor number and functional response of cholinoceptive neurons. Various measures are proposed to investigate the functional integrity of muscarinic receptors in AD patients. AD often has been characterized as a disorder produced by generalized cholinergic hypoactivity. Evidence for cortisol hypersecretion, abnormal dexamethasone suppression, and the occurrence of depressive symptoms, motoric dysfunction and sleep abnormalities in AD patients is more consistent with regional cholinergic hyperactivity than generalized hypoactivity. Resolution of these discrepancies could shed new light on the pathophysiology and treatment strategies for AD. Cholinoceptive neurons could be hypersensitive, subsensitive or have unaltered responsivity. These options would have very different treatment implications. New developments in outcome assessment which are capable of discriminating varieties of differential response to treatment can spur treatment development and improve quality of care for patients with complex disorders such as AD.     

Specific binding of the mononuclear phagocyte colony-stimulating factor CSF-1 to the product of the v-fms oncogene.

Cells transformed by the McDonough strain of feline sarcoma virus (SM-FeSV) express a v-fms-encoded glycoprotein whose expression at the cell surface correlates with the transformed phenotype. The mouse mononuclear phagocyte growth factor CSF-1 specifically binds to SM-FeSV-transformed cells at high-affinity sites indistinguishable from those detected on normal feline macrophages. A monoclonal antibody to a v-fms-encoded epitope competed for CSF-1 binding to SM-FeSV-transformed cells, and chemical crosslinking demonstrated that murine CSF-1 bound to the v-fms gene product at the cell surface. Although SM-FeSV-transformed fibroblast lines were found to secrete CSF-1, the growth of transformed cells was not affected by antibodies to the v-fms gene product or to the growth factor. Tyrosine phosphorylation of the v-fms products in membranes was observed in the absence of CSF-1 and was not enhanced by addition of the murine growth factor. The data support the hypothesis that the c-fms protooncogene product is related, and possibly identical, to the CSF-1 receptor and suggest that the v-fms-encoded kinase functions in the absence of an exogenous growth factor.     

Meniscal abnormalities: prospective correlation of double-contrast arthrography and arthroscopy

In a prospective study conducted over a 12-month period, 30 patients underwent double-contrast arthrography of the knee followed by arthroscopic study. An 80% correlation rate was found between results. Arthrography had a higher rate of accuracy (93%) than arthroscopy (84%) and had a 7% false-positive and 0% false-negative rate. A commonly overlooked arthrographic sign--the triple-S or stuck sail sign--was 91% accurate in the prediction of meniscal tears. The complementary nature of the two examinations is discussed.     

Academic Achievement of Children with Epilepsy

The academic achievement scores of 122 children with epilepsy were examined in relation to demographic and clinical seizure variables. As a group, these children were making less academic progress than expected for their age and IQ level. Academic deficiencies were greatest in arithmetic, followed by spelling, reading, comprehension, and word recognition. Results of the multiple regression analyses indicated a modest combined predictive significance of the demographic and clinical seizure variables for academic performance. In addition, the magnitude of these relationships varied by academic area. Among the individual variables examined the strongest correlates of academic performance were age of the child, age of seizure onset, lifetime total seizure frequency, and presence of multiple seizures (absence and tonic-clonic). These results are discussed in relation to developing an understanding of the factors which underlie academic vulnerability in children with epilepsy.     

Multiple Implants for First Molar Prosthodontics

Problems that can occur when single implants are utilized to restore first molar teeth include the frequent loosening of screws, as well as screws and/or implant breakage. These may result from torquing and rotational movements of the prosthesis during masticatory and parafunctional mandibular movements. When sufficient bone and mesio-distal restorative space is present, the placement of two implants should be considered.