Target similarity affects saccade curvature away from irrelevant onsets

Saccade curvature away from visual distractors is a measure of the salience of these distractors for the oculomotor system. Three experiments are reported in which the integration of luminance onset signals and target similarity signals is examined, using a saccade curvature paradigm. Observers made saccades to a no-onset colour target in one of two positions on the vertical meridian. On most trials, an abrupt onset distractor that was either similar or dissimilar to the target appeared left or right on the horizontal midline. Saccades curved away from the irrelevant onsets; however, the amount of curvature was modulated by target similarity only when the onset appeared before the target (experiment 2) or when saccade initiation was delayed (experiment 3). These results suggest that the initial response to the onset is stimulus-driven and mediated by its transient component. Over time, the response is integrated with and augmented by top-down inputs. Visual and non-visual signals converge onto a common motor map to determine an item's salience.     

Prolactin induces ERalpha-positive and ERalpha-negative mammary cancer in transgenic mice

The role of prolactin in human breast cancer has been controversial. However, it is now apparent that human mammary epithelial cells can synthesize prolactin endogenously, permitting autocrine/paracrine actions within the mammary gland that are independent of pituitary prolactin. To model this local mammary production of prolactin (PRL), we have generated mice that overexpress prolactin within mammary epithelial cells under the control of a hormonally nonresponsive promoter, neu-related lipocalin (NRL). In each of the two examined NRL-PRL transgenic mouse lineages, female virgin mice display mammary developmental abnormalities, mammary intraepithelial neoplasias, and invasive neoplasms. Prolactin increases proliferation in morphologically normal alveoli and ducts, as well as in lesions. The tumors are of varied histotype, but papillary adenocarcinomas and adenosquamous neoplasms predominate. Neoplasms can be separated into two populations: one is estrogen receptor alpha (ERalpha) positive (greater than 15% of the cells stain for ERalpha), and the other is ERalpha- (<3%). ERalpha expression does not correlate with tumor histotype, or proliferative or apoptotic indices. These studies provide a mouse model of hormonally dependent breast cancer, and, perhaps most strikingly, a model in which some neoplasms retain ERalpha, as occurs in the human disease.     

Making the case for a qualitative study of medical errors in primary care

In the interest of publicizing examples of funded qualitative health research, the authors share a proposal to the Agency for Healthcare Research and Quality in Washington, D.C., in which they sought to elicit patient stories of preventable problems in their primary health care that were associated with psychological or physical harms. These stories would allow for the construction of a tentative typology of errors and harms as experienced by patients and the contrasting of this with errors and harms reported by primary care physicians in the United States and other countries. The authors make explicit the anticipated concerns of reviewers more accustomed to quantitative research proposals and the arguments and strategies employed to address them.     

Cooling strategies for patients with severe cerebral insult in ICU (Part 2)

Critically ill patients who have sustained a severe cerebral insult will be actively cooled should they develop an elevated body core temperature. Patients who require therapeutic hypothermia for neuroprotection may require the same cooling strategies. A literature review suggested limited evidence to support cooling strategies currently used within one intensive care unit. An experimental approach was used to examine the effects of paracetamol and four external cooling strategies on patients with severe cerebral insult It is suggested that paracetamol is effective in reducing body core temperature and that fans may not. However, data obtained from the study of the four external cooling strategies were inconclusive.     

Development and current functioning in adolescents with Asperger syndrome: a comparative study

Adolescents with Asperger syndrome (AS: without delay in speech development, diagnosed according to ICD-10 clinical criteria) were compared with a group with high-functioning autism (HFA: all with delayed speech development), and a group with conduct disorder (CD). Family and genetic studies suggest that Asperger syndrome and autism form part of the same spectrum, whereas the social impairments in conduct disorder are assumed to have different origins. The aims were to explore the relationships between early speech development and other aspects of functioning in autistic disorders, and to compare autistic and nonautistic social impairments. Early and current behaviour and IQ profiles were investigated. The CD group were clearly different from both the AS and HFA groups. The AS group tended to have less severe early behavioural abnormalities than the HFA group, and were unlikely to have speech abnormalities, but other communicative, social, and restricted/ stereotyped behavioural difficulties were largely of a similar pattern to the abnormalities in the HFA group. Eighty per cent of the AS group met criteria for autism on the diagnostic algorithm associated with the Autism Diagnostic Interview-Revised. By adolescence, the AS group were reported to be as abnormal as the HFA group but in structured 1:1 interaction their conversation was better. IQ profile in the AS group showed relative strength on verbal measures, unlike the HFA group, but relatively good performance on the Block Design subtest of the WISC/WAIS was a feature of both the AS and HFA groups. The results indicate closely similar behavioural manifestations may arise by adolescence despite differences in speech development. Follow-up studies and further family investigations will be required to clarify the origins of these and other patterns of autistic development.     

Hip fracture mortality and morbidity--can we do better?

AIMS: To determine the mortality and morbidity from fractures of the neck of femur in Christchurch Hospital and to determine the extent that hip fracture patients are investigated and treated for osteoporosis. METHODS: All patients treated for a fractured hip at Christchurch Hospitals between May 1998 and April 1999 were identified. Their radiographs were reviewed and each fracture was classified. Dates of death were recorded where applicable. Surviving patients were contacted at least twelve months after their fracture and asked questions relating to functional outcome following surgery. The numbers of patients who had ever had a bone density scan, treatment for osteoporosis and/or a measurement of vitamin D were recorded. RESULTS: There were 331 fractures among 329 patients (242 women, 87 men), mean age of 79.7 (standard deviation 10.5) years. Twelve-month mortality was 26%. Men had a higher mortality rate than women for all fracture types that was independent of age. Follow up of the 231 surviving patients 12-24 months later revealed 27% still had pain and 60% had worsened mobility that they attributed to the fracture. Worsened mobility affected people living at home more than people living in institutional care. 32 people (15%) had had a vitamin D concentration measured and in 22 of these (69%) levels were below the reference range. CONCLUSIONS: The mortality and morbidity after hip fracture is high, especially in men. There were few significant correlates with greater morbidity except for fixation by hemi arthroplasty. More attention to hip fracture prevention is needed. Few subjects were on any therapy for osteoporosis other than calcium supplements. Vitamin D deficiency is an important but under-recognised condition.     

Differential protein expression in hypertrophic heart with and without hypertension in spontaneously hypertensive rats

Although cardiac hypertrophy in hypertension has been well recognized, the molecular mechanisms for the development of hypertrophy are still largely unknown. In this study, the protein expression profiles of left ventricular myocardia in spontaneously hypertensive rats （SHR） and Wistar-Kyoto （WKY） rats at different ages were analyzed using 2-DE in combination with MALDI-TOF/TOF MS/MS. The results showed that 20 proteins were modulated in the hypertrophic myocardium. Out of these modulated proteins, 13 proteins presented significant changes in SHR at an early stage prior to the development of sustained hypertension, while the changes of the other 7 protein expres- sions occurred only at a late stage in SHR when the blood pressure was significantly elevated, and were largely reversible by treatment with rennin-angiotensin-aldosterone system inhibitors losartan or enalapril. These data demonstrate that the changes in energy metabolism in the hypertrophied heart favor an increase in glycolysis and a decrease in oxidation of fatty acid and glucose, which occur at an early stage in SHR without hypertension. Our results also provide evidence to support the hypothesis that oxidative stress plays an important role in the development of hypertensive cardiac hypertrophy.