Cone cGMP-gated channel mutations and clinical findings in patients with achromatopsia, macular degeneration, and other hereditary cone diseases

Unrelated patients with achromatopsia, macular degeneration with onset under age 50 years, cone degeneration or dysfunction, cone-rod degeneration, or macular malfunction were screened for mutations in the three genes known to be associated with achromatopsia: the GNAT2 gene encoding the alpha subunit of cone transducin and the CNGA3 and CNGB3 genes encoding the alpha and beta subunits of the cone cGMP-gated cation channel. We found no examples of patients with GNAT2 mutations. Out of 36 achromats, 12 (33%) had mutations in CNGA3 (13 different mutations including five novel mutations) and 12 (33%) had mutations in CNGB3 (six different mutations including four novel mutations). All achromats with CNG mutations had residual, presumably cone function as determined by computer-averaged 30-Hz electroretinograms (ERGs). There was considerable variability in acuity and color vision, with most patients having acuities of 20/200-20/400 and complete absence of color perception, and others having acuities of 20/25-20/40 and some color vision. Two pseudodominant achromatopsia cases were uncovered, both with CNGA3 mutations, including one family in which some compound heterozygotes with achromatopsia mutations were clinically unaffected. We found two novel CNGB3 changes in three patients with juvenile macular degeneration, a phenotype not previously associated with mutations in the cone channel subunits. These patients had subnormal acuity (20/30-20/60), normal to subnormal color vision, and normal to subnormal full-field cone ERG amplitudes. Our results indicate that some patients with channel protein mutations retain residual foveal cone function. Based on our findings, CNGB3 should be considered as a candidate gene to be evaluated in patients with forms of cone dysfunction, including macular degeneration.     

The use of urine proteomic and metabonomic patterns for the diagnosis of interstitial cystitis and bacterial cystitis

The advent of systems biology approaches that have stemmed from the sequencing of the human genome has led to the search for new methods to diagnose diseases. While much effort has been focused on the identification of disease-specific biomarkers, recent efforts are underway toward the use of proteomic and metabonomic patterns to indicate disease. We have developed and contrasted the use of both proteomic and metabonomic patterns in urine for the detection of interstitial cystitis (IC). The methodology relies on advanced bioinformatics to scrutinize information contained within mass spectrometry (MS) and high-resolution proton nuclear magnetic resonance (1H-NMR) spectral patterns to distinguish IC-affected from non-affected individuals as well as those suffering from bacterial cystitis (BC). We have applied a novel pattern recognition tool that employs an unsupervised system (self-organizing-type cluster mapping) as a fitness test for a supervised system (a genetic algorithm). With this approach, a training set comprised of mass spectra and 1H-NMR spectra from urine derived from either unaffected individuals or patients with IC is employed so that the most fit combination of relative, normalized intensity features defined at precise m/z or chemical shift values plotted in n-space can reliably distinguish the cohorts used in training. Using this bioinformatic approach, we were able to discriminate spectral patterns associated with IC-affected, BC-affected, and unaffected patients with a success rate of approximately 84%.     

CD5 (OKT1) augments CD3-mediated intracellular signaling events in human T lymphocytes

CD5 is expressed on thymocytes, all mature T cells, and a subset of mature B cells, and probably contributes to T-cell–B-cell adhesion. We assessed whether CD5-crosslinking by mAb augments T-cell stimulation. Plate-bound anti-CD5 or anti-CD3 mAb alone had no effect on any of the assessed activation parameters of resting T cells. However, concomitant signaling through both CD5 and CD3 by plate-bound antibodies resulted in marked increases in T-cell surface CD69 expression and T-cell metabolism, as assessed by the T cell's ability to reduce 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxylmethoxyphenyl)-2-(4-sulphophenyl)-2H-tetrazolium (MTS) to formazen. In addition, simultaneous cross-linking of CD5 and CD3 caused a significant (p < 0.001) increase in phosphatidylinositol hydrolysis in resting T cells compared to stimulation with anti-CD3 mAb alone or anti-CD3 mAb plus anti-CD5 isotype control antibody. These results indicate that CD5 augments signaling through CD3 and consequently functions as a costimulatory molecule for resting T cells.     

Prevalence and incidence of HIV among incarcerated and reincarcerated women in Rhode Island

This study explores recent temporal trends in HIV prevalence among women entering prison and the incidence and associated risk factors among women reincarcerated in Rhode Island. Results from mandatory HIV testing from 1992 to 1996 for all incarcerated women were examined. In addition, a case control study was conducted on all seroconverters from 1989 to 1997. In all, 5836 HIV tests were performed on incarceration in 3146 women, 105 of whom tested positive (prevalence, 3.3%). Between 1992 and 1996, the annual prevalence of HIV among all women known to be HIV-positive was stable (p = .12). Age >25 years, nonwhite race, and prior incarceration were associated with seropositivity. Of 1081 initially seronegative women who were retested on reincarceration, 12 seroconverted during 1885 person-years (PY) of follow-up (incidence, 0.6/100 PY). Self-reported injection drug use (IDU; odds ratio [OR], 3.7; 95% confidence interval [CI], 1.3-10.1) was significantly associated with seroconversion, but sexual risk was not (OR, 1.1; 95% CI, 0.4-3.5). Incarceration serves as an opportunity for initiation of treatment and linkage to community services for a population that is at high risk for HIV infection.     

Clostridium difficile vaccine and serum immunoglobulin G antibody response to toxin A

There is a strong association between serum antibody responses to toxin A and protection against Clostridium difficile diarrhea. A parenteral C. difficile toxoid vaccine induced very-high-level responses to anti-toxin A immunoglobulin G (IgG) in the sera of healthy volunteers. After vaccination, the concentrations of anti-toxin A IgG in the sera of all 30 recipients exceeded the concentrations that were associated with protection in previous clinical studies. Furthermore, the median concentration of serum anti-toxin A IgG in the test group was 50-fold higher than the previous threshold. These findings support the feasibility of using a vaccine to protect high-risk individuals against C. difficile-associated diarrhea and colitis.     

Spontaneous aberrant crypt foci in Apc1638N mice with a mutant Apc allele

The Apc1638N/+ mouse has a chain-terminating mutation in one allele of the adenomatous polyposis coli (Apc) gene that is similar to most mutations observed in the human familial adenomatous polyposis syndrome. Aberrant crypt foci (ACF), the earliest identified neoplastic lesions in the colon, are morphologically abnormal structures that are identifiedmicroscopically in the grossly normal colonic mucosas of rodents treated with colon carcinogens and of human patients. The colons and cecums of 62 Apc1638N/+ mice were evaluated for the spontaneous occurrence of ACF and tumors. Both male and female mice were killed at different times between 5 and 28 weeks of age. Wild-type littermates, ie, Apc(+/+) mice, at 22 to 26 weeks of age served as controls. ACF were identified in 97% of the Apc1638N/+ mice starting at 5 weeks of age and not in any wild-type littermates. Although the number of ACF increased with age (P < 0.0001), the average number of crypts per focus of the ACF did not increase significantly. In addition, wild-type Apc protein was detected by immunohistochemistry in all 22 ACF evaluated. Together these data suggest that heterozygous loss of Apc may be sufficient to initiate ACF in these mice and that these mice may be suitable models to study the interaction of environmental factors with an inherited mutation of the Apc gene that is associated with colon cancer.