A locus for posterior polymorphous corneal dystrophy (PPCD3) maps to chromosome 10

Posterior polymorphous corneal dystrophy (PPCD) is an autosomal dominant disorder characterized by corneal endothelial abnormalities, which can lead to blindness due to loss of corneal transparency and sometimes glaucoma. We mapped a new locus responsible for PPCD in a family in which we excluded the previously reported PPCD locus on 20q11, and the region containing COL8A2 on chromosome 1. Results of a 317-marker genome scan provided significant evidence of linkage of PPCD to markers on chromosome 10, with single-point LOD scores of 2.63, 1.63, and 3.19 for markers D10S208 (at (circumflex)theta = 0.03), D10S1780 (at (circumflex)theta = 0.00), and D10S578 (at (circumflex)theta = 0.06). A maximum multi-point LOD score of 4.35 was found at marker D10S1780. Affected family members shared a haplotype in an 8.55 cM critical interval that was bounded by markers D10S213 and D10S578. Our finding of another PPCD locus, PPCD3, on chromosome 10 indicates that PPCD is genetically heterogeneous. Guttae, a common corneal finding sometimes observed along with PPCD, were found among both affected and unaffected members of the proband's sib ship, but were absent in the younger generations of the family. Evaluation of phenotypic differences between family members sharing the same affected haplotype raises questions about whether differences in disease severity, including differences in response to surgical interventions, could be due to genetic background or other factors independent of the PPCD3 locus.     

CAG nucleotide repeat profiles in persons with schizophrenia or schizoaffective disorders with and without tardive dyskinesia: pilot study.

Tardive dyskinesia (TD) is a drug-induced syndrome of involuntary movements often associated with neuroleptic treatment of psychiatric conditions. Huntington's disease (HD) and other neurological conditions are caused by CAG nucleotide repeat expansions in specific genes. We, therefore, explore the hypothesis that TD may be related to CAG repeat expansion by using the repeat expansion detection (RED) method as a measure of CAG content without knowledge of the location of the responsible gene. The number of CAG repeats ([CAG](n)) from persons with schizophrenia or schizoaffective disorders with (n = 10) and without (n = 9) TD are determined. A comparison of [CAG](n) in persons with (56.90 +/- 23.45 repeats) and without (57.00 +/- 19.35 repeats) TD was not statistically different. The total [CAG](n) was determined by combining [CAG](n) for both groups. The median of 45 repeats was used to divide the total into two groups (SG1 and SG2 with smaller and larger [CAG](n) fragments, respectively) and a means analysis of the two subgroups based on [CAG](n) demonstrated that SG1 (n = 10 samples at 45 repeats per sample, mean [CAG](n) = 45.00 +/- 0.00) was significantly smaller than SG2 (n = 9, ranging from 48 to 120 repeats, mean = 70.22 +/- 24.83; P < 0.005). Thus, this lends support to the idea of CAG repeat expansions in the study population. Results are encouraging that a larger population and a more structured subject selection process may yield more meaningful information about the relationship between CAG repeat expansion and TD.     

Fluoroscopy guided transperineal percutaneous permanent 125iodine implantation of prostate cancer

The transperineal percutaneous template permanent iodine interstitial brachytherapy under "C-arm" fluoroscopic guidance is a simple, easily-learned, accurate and rapid procedure which can be performed without subjecting the patient to celiotomy. We have treated 58 patients by the transperineal percutaneous permanent interstitial brachytherapy. The use of transperineal percutaneous technique with C-arm fluoroscopic guidance improves the symmetry and dosimetry of the implant. This results in reduction of the incidence of chronic radiation-induced complications. In the group of 22 patients who underwent brachytherapy without celiotomy and lymphadenectomy and without adjuvant external-beam radiotherapy, there were no major complications.     

Extensive surgical excision of large hemispheric “malignant” astrocytoma in a 6-week-old infant

A massive hemispheric high-grade astrocytoma, diagnosed in a 6-week-old infant, was totally excised by means of two craniotomies. The child is still alive and well with minimal neurological dysfunction 1.5 years after operation. This case report illustrates the benefit of aggressive surgical excision (without radiation or chemotherapy) of massive malignant neonatal astrocytomas. While surgical deficits may be minimized by the plasticity of the developing nervous system, extensive excision may yield occasional long-term palliation.     

Racism,stress and health in Asian Americans: A structural equation analysis of mediation and social support group differences

The buffering effect of social support on the negative effects of racism exposure on health outcomes has been mixed in prior studies regarding Asian Americans. Based on the stress-coping framework and using structural equation modelling (SEM) methods, we tested a theoretical model portraying simultaneous mediational paths from racism exposure to general physical and mental health through racism-related stress. Bootstrap analysis was used to test the indirect effects present in the model. Additionally, multi-group SEM analysis was conducted to investigate the moderation effect of social support from family and friends on the paths in the model. The sample consisted of 310 Asian American adults who completed an online survey. The results from the two-step SEM analysis and bootstrap analysis supported the theoretical model—racism exposure can simultaneously have a negative indirect effect on Asian Americans' physical and mental health via racism-related stress. Multi-group SEM analysis showed that there were no differences in model path coefficients based on having varying levels of social support from friends or family.     

Acceptability and Feasibility of Geographically Explicit Ecological Momentary Assessment Among Men Who Have Sex with Men

Syphilis among men who have sex with men (MSM) has increased greatly in the past twenty years in the U.S. Geographically explicit ecological momentary assessment (GEMA), in which behaviors are geotagged and contextualized in time and space, may contribute to a greater understanding of transmission risk. The objective was to determine the acceptability and feasibility of GEMA for assessing HIV and syphilis transmission risk behaviors among a sample of MSM. Participants responded to a brief survey five times a day for two weeks. Feasibility was measured by participant recruitment, enrollment, prompts received and answered, geotagged prompts, and technical interference with data collection. Acceptability was measured by ratings of enjoyment and willingness for future participation. Summaries of five behavioral measures from the brief survey were calculated. Among the 83 participants contacted, 67.5% (56) expressed interest, 98% (55) were scheduled, and 81.8% (45) were enrolled. Participants answered 78.3% (2,277) of prompts received and 87.7% (1,998) of answered prompts were geotagged. Overall, 70.5% (31) enjoyed participating and 91.1% (41) were willing to participate in the future. Among prompts answered, missingness was low for five behavioral measures (range 0.2% (4) to 0.7% (16)). Feasibility and acceptability were high and missingness was low on behavioral measures in this MSM study population. Most participants reported that they would participate again. Future work should focus on whether GEMA improves our understanding of syphilis and HIV transmission risk.

     

On-line radiotherapy imaging with an array of fiber-optic image reducers

In the optical approach for on-line radiotherapy imaging, a large metal sheet-fluorescent screen combination is used to convert the radiation intensity distribution into a visible light image. Data are then captured via a mirror with a camera located out of the beam. Although usable portal images can be acquired, presence of the large mirror renders the system impractical in many treatment geometries. We have overcome this limitation by replacing the mirror with an array of 16 by 16 bundles of plastic fiber-optic image reducers. Each bundle, in turn, is made up of 16 by 16 individual optical fibers. The total of 256 by 256 fibers spans an input area of 40 cm by 40 cm with each individual fiber viewing an area of 1.6 mm by 1.6 mm. Within a height of 12 cm, each fiber is reduced to an area of 0.1 mm by 0.1 mm. The reduced portal image is then turned and "piped" to a final 3.0 cm by 3.0 cm output area. For data acquisition and digitization, the fiber output is directly coupled to the sensor of a TV camera interfaced to a small computer via a 512 by 512 frame grabber. In this initial evaluation, the imaging system has been characterized in terms of its line spread function, noise and resistance to radiation damage. Adequate phantom and patient images are presented.