Biological characterization of Drosophila Rapgap1, a GTPase activating protein for Rap1

The activity of Ras family proteins is modulated in vivo by the function of GTPase activating proteins, which increase their intrinsic rate of GTP hydrolysis. We have isolated cDNAs encoding a GAP for the Drosophila Rap1 GTPase. Drosophila Rapgap1 encodes an 850-amino acid protein with a central region that displays substantial sequence similarity to human RapGAP. This domain, when expressed in Escherichia coli, potently stimulates Rap1 GTPase activity in vitro. Unlike Rap1, which is ubiquitously expressed, Rapgap1 expression is highly restricted. Rapgap1 is expressed at high levels in the developing photoreceptor cells and in the optic lobe. Rapgap1 mRNA is also localized in the pole plasm in an oskar-dependent manner. Although mutations that completely abolish Rapgap1 function display no obvious phenotypic abnormalities, overexpression of Rapgap1 induces a rough eye phenotype that is exacerbated by reducing Rap1 gene dosage. Thus, Rapgap1 can function as a negative regulator of Rap1-mediated signaling in vivo.     

Screening for diabetic retinopathy in primary care with a mobile fundal camera--evaluation of a South African pilot project.

BACKGROUND AND AIMS: In South Africa diabetes makes a significant contribution to the burden of disease. Diabetic retinopathy is a leading cause of adult blindness, and screening can reduce the incidence. This project aimed to implement and evaluate a new service for retinal screening that uses a non-mydriatic mobile fundal camera in primary care. This is the first time such a service has been evaluated in an African primary care context. METHODS: The service was implemented as an operational research study at three community health centres and data were collected to evaluate the operational issues, screening, reporting and referral of patients. RESULTS: Out of 400 patients screened 84% had a significantly reduced visual acuity, 63% had retinopathy (22% severe nonproliferative, 6% proliferative and 15% maculopathy), 2% of eyes could not be screened and 14% of patients required dilatation. Referral was necessary in 27% of cases for cataracts, in 7% for laser treatment and in 4% for other specialist services. Repeat photography was needed in 8% and urgent follow-up in 12%. A SWOT analysis of the pilot project was completed and recommendations were made on how to integrate it into the district health system. CONCLUSION: Screening with a fundal camera improved the quality of care for diabetic patients and is feasible in the South African public sector, primary care setting. A single technician should be able to photograph almost 10,000 patients a year.     

Gliadin antibody detection in gluten enteropathy

Circulating antigliadin antibody has been described in patients with gluten enteropathy although the prevalence varies in different studies. It has been suggested that the investigation for antigliadin antibody might be useful as a screening test. The object of the present study was to evaluate two different techniques for assaying these antibodies — an indirect immunofluorescent method and an enzyme-linked immunosorbent assay (ELISA). Antibodies were assayed in the sera of 102 patients in whom jejunal biopsies were also obtained. The specificity of both tests was greater than 95%, and the correlation between the presence of antibody and histology was significant (p < 0.005), though the sensitivity of each test was less than 70%.     

ASSESSING THE IMPACT OF A CHILD WITH SPINA BIFIDA ON THE FAMILY

This study examined the characteristics of families which may be more vulnerable than others to the impact of caring for a child with spina bifida. Morbidity and the use of health services were unexpectedly high. The impact on the family was related less to clinical diagnoses than to the characteristics of the child's functioning in the home and of the family. Major predictors of greater impact on the family were the number of the child's activities of daily living, parental perceptions of the child's health, low maternal educational attainment, low family income, the number of adults in the family, insurance status, the number of visits to a doctor in the month before the interview, and whether the adults in the family were employed. These results reinforce the need for assessments to include the child's function in the home, and for additional resources to help some families care for their child.     

An intervention for multiethnic obese parents and overweight children.

The purpose of this pilot study was to determine the effects of the addition of coping skills training for obese multiethnic parents whose overweight children were attending a weight management program. At 6 months, parents in the experimental group had significantly lower body mass index (BMI) and body fat percentage (BFP) and higher numbers of pedometer steps compared with those in the control group. Parents in the experimental group also demonstrated significant improvement in interpersonal relationships, behavior control, and stress management compared with those in the control group. Children in the experimental group demonstrated trends toward decreased BMI and BFP and increased pedometer steps.