Variation in small bowel length: factor in achieving total enteroscopy?

BACKGROUND AND AIM: Estimation of small bowel length is of interest following the recent development of device-assisted enteroscopy. This new technology allows access to the deep small bowel, but rates of examination of the entire small bowel (total enteroscopy) differ between study populations. Variation in small bowel length could factor into this observed irregularity in total enteroscopy rates. Medical literature contains limited information regarding small bowel length in living patients and conflicting data regarding small bowel length and its relationship to height and weight. We carried out small bowel measurements on surgical patients to further define the total length of the small bowel and its relationship to height, weight and body mass index (BMI). METHODS: Measurement of ileojejunal length on 91 surgical patients undergoing laparotomy for routine indications. Demographic data were collected for each subject, including height, weight and BMI. RESULTS: Small bowel length was found to vary widely between individuals (average 998.52 cm, range 630-1510 cm). Linear regression analysis demonstrated a statistically significant relationship between small bowel length and height (regression coefficient = 0.0561, P-value = 0.0238). A linear relationship between small bowel length and weight or BMI was not observed. CONCLUSIONS: Length of the small bowel in humans is pertinent to advances in deep enteroscopy and existing surgical applications such as intestinal bypass and prevention of short gut syndrome. If average small bowel length varies with height, total enteroscopy may be easier to achieve in patients who are short in stature.

HSV-1 latent rabbits shed viral DNA into their saliva.

BACKGROUND: Rabbits latent with HSV-1 strain McKrae spontaneously shed infectious virus and viral DNA into their tears and develop recurrent herpetic-specific corneal lesions. The rabbit eye model has been used for many years to assess acute ocular infections and pathogenesis, antiviral efficacy, as well as latency, reactivation, and recurrent eye diseases. This study used real-time PCR to quantify HSV-1 DNA in the saliva and tears of rabbits latent with HSV-1 McKrae. METHODS: New Zealand white rabbits used were latent with HSV-1 strain McKrae and had no ocular or oral pathology. Scarified corneas were topically inoculated with HSV-1. Eye swabs and saliva were taken from post inoculation (PI) days 28 through 49 (22 consecutive days). Saliva samples were taken four times each day from each rabbit and the DNA extracted was pooled for each rabbit for each day; one swab was taken daily from each eye and DNA extracted. Real-time PCR was done on the purified DNA samples for quantification of HSV-1 DNA copy numbers. Data are presented as copy numbers for each individual sample, plus all the copy numbers designated as positive, for comparison between left eye (OS), right eye (OD), and saliva. RESULTS: The saliva and tears were taken from 9 rabbits and from 18 eyes and all tested positive at least once. Saliva was positive for HSV-1 DNA at 43.4% (86/198) and tears were positive at 28.0% (111/396). The saliva positives had 48 episodes and the tears had 75 episodes. The mean copy numbers ± the SEM for HSV-1 DNA in saliva were 3773 ± 2019 and 2294 ± 869 for tears (no statistical difference). CONCLUSION: Rabbits latent with strain McKrae shed HSV-1 DNA into their saliva and tears. HSV-1 DNA shedding into the saliva was similar to humans. This is the first evidence that documents HSV-1 DNA in the saliva of latent rabbits.

Rabbit and mouse models of HSV-1 latency, reactivation, and recurrent eye diseases.

The exact mechanisms of HSV-1 establishment, maintenance, latency, reactivation, and also the courses of recurrent ocular infections remain a mystery. Comprehensive understanding of the HSV-1 disease process could lead to prevention of HSV-1 acute infection, reactivation, and more effective treatments of recurrent ocular disease. Animal models have been used for over sixty years to investigate our concepts and hypotheses of HSV-1 diseases. In this paper we present descriptions and examples of rabbit and mouse eye models of HSV-1 latency, reactivation, and recurrent diseases. We summarize studies in animal models of spontaneous and induced HSV-1 reactivation and recurrent disease. Numerous stimuli that induce reactivation in mice and rabbits are described, as well as factors that inhibit viral reactivation from latency. The key features, advantages, and disadvantages of the mouse and rabbit models in relation to the study of ocular HSV-1 are discussed. This paper is pertinent but not intended to be all inclusive. We will give examples of key papers that have reported novel discoveries related to the review topics.

The polycomb group protein Bmi1 binds to the herpes simplex virus 1 latent genome and maintains repressive histone marks during latency.

The mechanism by which herpes simplex virus 1 (HSV-1) establishes latency in sensory neurons is largely unknown. Recent studies indicate that epigenetic modifications of the chromatin associated with the latent genome may play a key role in the transcriptional control of lytic genes during latency. In this study, we found both constitutive and facultative types of heterochromatin to be present on the latent HSV-1 genome. Deposition of the facultative marks trimethyl H3K27 and histone variant macroH2A varied at different sites on the genome, whereas the constitutive marker trimethyl H3K9 did not. In addition, we show that in the absence of the latency-associated transcript (LAT), the latent genome shows a dramatic increase in trimethyl H3K27, suggesting that expression of the LAT during latency may act to promote an appropriate heterochromatic state that represses lytic genes but is still poised for reactivation. Due to the presence of the mark trimethyl H3K27, we examined whether Polycomb group proteins, which methylate H3K27, were present on the HSV-1 genome during latency. Our data indicate that Bmi1, a member of the Polycomb repressive complex 1 (PRC1) maintenance complex, associates with specific sites in the genome, with the highest level of enrichment at the LAT enhancer. To our knowledge, these are the first data demonstrating that a virus can repress its gene transcription to enter latency by exploiting the mechanism of Polycomb-mediated repression.

The high prevalence of herpes simplex virus type 1 DNA in human trigeminal ganglia is not a function of age or gender.

The purpose of this study was to determine the presence and copy numbers of herpes simplex virus type 1 (HSV-1) DNA in human trigeminal ganglia (TG) with respect to age, gender, and postmortem interval (PMI). Human TG (n = 174, obtained from the Oregon Brain Bank, with data on age, gender, and PMI) were analyzed for HSV-1 DNA copies (HSV-1 DNA polymerase gene) by using real-time PCR. We found that 89.1% (131/147) of subjects and 90.1% (155/174) of TG contained HSV-1 DNA. The copy numbers of HSV-1 DNA in the positives ranged from very high (>10(6)) to very low (5). These data confirm and strengthen our previous findings that subjects were positive for HSV-1 DNA in tears (46/50; 92%) and saliva (47/50; 94%). These TG data and tear and saliva data demonstrated considerable variability in copy numbers of HSV-1 DNA per subject. Statistical analysis showed no significant relationship between gender and copy number, age and copy number, or PMI and copy number for each pair of variables. A factorial analysis of gender, age, and PMI with respect to copy number also showed no statistical significance. This is the first study that provides statistical analysis that documents that the prevalence of HSV-1 DNA in the human TG is not a function of either gender or age.

Effect of human apolipoprotein E genotype on the pathogenesis of experimental ocular HSV-1.

The isoform-specific role of human apolipoprotein E (apoE) has been assessed in a mouse model of ocular herpes. Female, age-matched transgenic mice knocked-in for the human allele apoE3 or apoE4 and their parent C57Bl/6 mice were inoculated corneally with HSV-1 strain KOS. Ocular HSV-1 pathogenesis was monitored through viral replication and clinical progression of stromal opacity and neovascularization by slit-lamp examination. Establishment of latency was determined by analysis of HSV-1 DNA (copy number) by specific real-time PCR in the cornea, trigeminal ganglia (TG), and brain. Representative groups of transgenic mice were sacrificed for the analysis of gene expression of vascular endothelial growth factor (VEGF) by reverse-transcription PCR, and apoE expression by Western blot analysis. At 6days post-infection (P.I.), the ocular infectious HSV-1 titer was significantly higher (p<0.05) in apoE4 mice compared with apoE3 and C57Bl/6 mice. Corneal neovascularization in apoE4 mice was significantly higher (p<0.05) than apoE3 and C57Bl/6 mice. The onset of corneal opacity in apoE4 mice was accelerated during days 9-11 P.I.; however, no significant difference in severity was seen on P.I. days 15 and beyond. At 28 days P.I., infected mice of all genotypes had no significant differences in copy numbers (range 0-15) of HSV-1 DNA in their corneas, indicating that HSV-1 DNA copy numbers in cornea are independent of apoE isoform regulation. At 28 days P.I., both apoE4 and C57Bl/6 mice had a significantly higher (p=0.001) number of copies of HSV-1 DNA in TG compared with apoE3. ApoE4 mice also had significantly higher (p=0.001) copies of HSV-1 DNA in their TGs compared with C57Bl/6 mice. In brain, both apoE4 and C57Bl/6 mice had significantly higher numbers (p

Efficacy of a helicase-primase inhibitor in animal models of ocular herpes simplex virus type 1 infection.

PURPOSE: The aim of this study was to evaluate the effect of BAY 57-1293, a helicase-primase inhibitor, on herpes simplex virus type 1 (HSV-1) reactivation in mice and its efficacy on established disease in rabbits. METHODS: BALB/c mice latent for McKrae-strain HSV-1 were reactivated via heat stress, treated with BAY 57-1293, and their corneas were swabbed for virus or the trigeminal ganglia (TG) obtained for quantification of viral DNA. New Zealand white rabbits were infected and treated topically or orally in comparison with trifluridine or valacyclovir. RESULTS: Oral BAY 57-1293 suppressed reactivation in HSV-1-infected mice and reduced the viral load in TG up to four orders of magnitude. In the rabbits, the therapeutic efficacies of topical BAY 57-1293 and trifluridine were similar. Once-daily oral BAY 57-1293 was significantly more effective than valacyclovir and as effective as twice a day topical trifluridine. CONCLUSIONS: BAY 57-1293 may be more effective than valacyclovir, without the cytotoxicity or potential healing retardation seen with trifluridine. Oral BAY 57-1293 may be a substitute for eye drops as an effective treatment for herpetic keratitis and might be useful in treating stromal keratitis and iritis, as well as preventing recurrences of ocular herpes.

Apolipoprotein E modulates establishment of HSV-1 latency and survival in a mouse ocular model.

PURPOSE: To evaluate and compare the neuroinvasiveness and neurovirulence after ocular HSV-1 infection in ApoE knockout (ApoE-/-) and control C57BL/6 (ApoE+/+) mice. METHODS: Age-matched (14 weeks of age) C57BL/6J (ApoE+/+) female mice and female ApoE knockout (ApoE-/-) mice were inoculated by corneal scarification with HSV-1 strain 17Syn+. Analysis of HSV-1 replication in the mouse cornea was assessed through infectious virus assays of ocular (tear film) swabs at 1 to 5 days postinoculation (PI), slit-lamp examination (SLE) of corneas at PI days 1 to 7, and survival of infected mice. The contribution of apoE to the efficient establishment of latency was measured by real-time PCR quantitation of the latent viral genome in the trigeminal ganglia (TG) of infected mice. RESULTS: These studies showed that HSV-1 strain 17Syn+ replicates efficiently in the eyes, regardless of the host ApoE genotype. Neither the scoring of corneal pathology via SLE nor the infectious virus assay of the tear film resulted in any statistical differences between ApoE knockout (-/-) mice or the C57BL/6 (ApoE+/+) mice. In mice latently infected with HSV-1, our real-time PCR data showed significantly lower viral copy numbers of HSV-1 DNA in ApoE knockout (ApoE-/-) mice compared with C57BL/6 (ApoE+/+) mice. C57BL/6 (ApoE+/+) mice are more susceptible to the neurovirulence of HSV-1 strain 17Syn+ than female ApoE knockout (-/-) mice, as demonstrated by the fact that 50% (7/14) of the female C57BL/6 (ApoE+/+) mice inoculated with 17Syn+ died, as opposed to none (0/14) of the age- and sex-matched ApoE knockout mice. CONCLUSIONS: These data indicate that age (14 weeks) and sex-matched (female) wild mice with an ApoE null background (ApoE-/-) are more resistant and less efficient in the establishment of latency compared with ApoE+/+ mice in the C57BL/6 background.

HSV-1 DNA in tears and saliva of normal adults.

PURPOSE: To assess the frequency of shedding of herpes simplex virus type 1 (HSV-1) DNA in tears and saliva of asymptomatic individuals. METHODS: Fifty subjects without signs of ocular herpetic disease participated. Serum samples from all subjects were tested for HSV IgG antibodies by enzyme-linked immunosorbent assay (ELISA) and for HSV-1 by neutralization assay. HSV-1 DNA copy number and frequency of shedding were determined by real-time polymerase chain reaction (PCR) analysis of tear and saliva samples collected twice daily for 30 consecutive days. RESULTS: Thirty-seven (74%) of the 50 subjects were positive for HSV IgG by ELISA. The percentages of positive eye and mouth swabs were approximately equivalent: 33.5% (941/2806) and 37.5% (1020/2723), respectively. However, the percentage of samples with high HSV-1 genome copy numbers was greater in saliva than in tears, which may have been a result of the sample volume collected. Shedding frequency in tears was nearly the same in men (347/1003; 34.6%) and women (594/1705; 34.8%); in saliva, men had a higher frequency of shedding (457/1009; 45.3% vs. 563/1703; 33.1%, men versus women). Overall, 49 (98%) of 50 subjects shed HSV-1 DNA at least once during the course of the 30-day study. CONCLUSIONS: The percentage of asymptomatic subjects who intermittently shed HSV-1 DNA in tears or saliva was higher than the percentage of subjects with positive ELISA or neutralization antibodies to HSV. Because most HSV transmission occurs during asymptomatic shedding, further knowledge of the prevalence of HSV-1 DNA in tears and saliva is warranted to control its spread. Shedding is simple to study, and its suppression may be an efficient way to evaluate new antivirals in humans.

Long-term study of accommodative esotropia.

PURPOSE: This study aimed, using a large sample size, to determine the long-term results of standard treatment of accommodative esotropia and identify predictors of outcome while minimizing bias in data collection and analysis. METHODS: Data from all the files of a large, long-established pediatric ophthalmology practice were collected and analyzed using a masked protocol. The study included every esotropic patient who had been prescribed glasses. Criteria for patient inclusion were designed to conform to earlier studies by the authors. RESULTS: The database totaled 1307 patients, of who 354 met inclusion criteria. A greater difference between near and distance esodeviation (AC/A relationship) correlated with a higher rate of deterioration of accommodative esotropia control (P < 0.0001). Deterioration also positively correlated with earlier age of onset (P < 0.0001), inferior oblique overaction (P = 0.0005), and amblyopia (P < 0.005). CONCLUSIONS: This study demonstrates that a high AC/A relationship increases the likelihood of deterioration of accommodative esotropia, supporting the earlier studies, as well as the accuracy of this database. It also represents a new model for the utilization of clinical trials' bias-reduction principals in the analysis of retrospective data.

Effect of immunosuppression on gene expression in the HSV-1 latently infected mouse trigeminal ganglion.

PURPOSE: To determine alterations in expression of genes in herpes simples virus (HSV)-1 latently infected mouse trigeminal ganglia (TGs), after treatment with cyclophosphamide and dexamethasone. METHODS: Scarified corneas of female BALB/c mice were inoculated with HSV-1 strain McKrae. Four weeks after inoculation, cyclophosphamide and dexamethasone were intravenously injected to induce HSV-1 reactivation. Uninfected mice were also treated with the immunosuppressants. Four groups of animals were studied: uninfected, not treated; uninfected, drug treated; latently infected, not treated; and latently infected, drug treated. PolyA+ mRNA from the TGs of each group was reverse transcribed, labeled with 32P, incubated on a 1185-gene array membrane, and analyzed by phosphorimaging. As a comparison and to confirm microarray results, semiquantitative RT-PCR was also performed for selected genes. RESULTS: The immunosuppressive drugs significantly increased expression of two genes (calpactin 1 light chain and guanine nucleotide-binding protein alpha-stimulating polypeptide [GNAS]) in the ganglia of uninfected mice compared with those in untreated uninfected mice. Ten genes were shown to be significantly increased in the latent TGs of mice treated with immunosuppressants compared with latently infected untreated mice. These genes were prostaglandin E2 receptor EP4 subtype (PTGER4), insulin promoter factor 1 (IPF1), glutathione S-transferase mu2, cyclin D2, peripherin, plasma glutathione peroxidase, methyl CpG-binding protein 2, retinal S-antigen, ErbB2 proto-oncogene, and GNAS. Eight genes were shown to be significantly decreased in the HSV-1 latent TGs treated with the drugs, compared with untreated latently infected mice. These genes were peripheral myelin protein 22, decorin, transcription factor AP-1, dystroglycan 1, myelin protein zero, mitogen-activated protein kinase 3, prothymosin beta 4, and brain lipid-binding protein. The results obtained by semiquantitative RT-PCR were similar to those obtained by microarray analysis. CONCLUSIONS: Those genes with expression altered by immunosuppressive drug treatment may play an important role in ocular HSV-1 recurrence. Changes in expression of genes in the prostaglandin pathway, a transcription factor, and an enzyme in the cell cycle are considered especially important in HSV-1 reactivation by immunosuppression and are reviewed.

Deformation of the lamina cribrosa and anterior scleral canal wall in early experimental glaucoma.

PURPOSE: To test the hypothesis that pathophysiologic deformation of the lamina cribrosa and anterior scleral canal wall underlies the onset of confocal scanning laser tomography (CSLT)-detected optic nerve head (ONH) surface change in early experimental glaucoma. METHODS: Both eyes of four normal (two normal eyes) monkeys and four with early glaucoma (one eye with laser-induced IOP elevation, observed until the onset of CSLT-detected ONH surface change) were enucleated immediately after death and immersion fixed at IOP 0 mm Hg. In an additional four normal monkeys and five with early glaucoma, both eyes were cannulated, and IOP set to 10 mm Hg in one normal eye and either 30 or 45 mm Hg in the other (normal or early-glaucoma) eye. After 15 to 80 minutes of acute IOP elevation, these nine monkeys were perfusion-fixed. Within images of serial sagittal sections of the ONH tissues in all 17 monkeys, anterior lamina cribrosa position, laminar thickness, and scleral canal diameter were measured. For each parameter, differences between the two eyes of each monkey and between treatment groups were assessed by ANOVA. RESULTS: Within the eyes of the eight monkeys with IOP 0 mm Hg, the lamina cribrosa was posteriorly displaced and thicker and the scleral canal was enlarged at Bruch's membrane and at the anterior laminar insertion in the early-glaucoma eyes compared with the contralateral normal eyes (plastic deformation). Within the high-IOP normal eyes, the lamina cribrosa was posteriorly displaced compared with that in the low-IOP normal eyes, but there were no significant differences in laminar thickness or scleral canal diameter (normal compliance). Within the high-IOP early-glaucoma eyes, the lamina cribrosa was posteriorly displaced and thicker and the scleral canal enlarged, compared with both low-IOP normal eyes and high-IOP normal eyes (hypercompliant deformation). Differences in laminar position between the high-IOP early-glaucoma eyes and the contralateral low-IOP normal eyes (hypercompliant plus plastic deformation) were more than eight times greater than the differences between the high-IOP normal eyes and the contralateral low-IOP normal eyes (normal compliance). CONCLUSIONS: Both plastic (permanent) and hypercompliant deformation of the lamina cribrosa and anterior scleral canal wall are present in young adult monkey eyes with early experimental glaucoma. These findings suggest that damage to the ONH connective tissues occurs early in the monkey model of experimental glaucoma.

Coordinate activation of HIF-1 and NF-kappaB DNA binding and COX-2 and VEGF expression in retinal cells by hypoxia.

PURPOSE: Proinflammatory signaling mechanisms are implicated in the induction of retinal neovascularization (NV) during ischemic retinopathies. This study examined transcription factor (TF) AP-1, HIF-1, and NF-kappaB DNA-binding in relation to cyclooxygenase (COX)-2 and VEGF RNA and protein levels in hypoxia-triggered monkey choroidal retinal (RF/6A) endothelial cells. Effects of the carboxamide CGP43182 were tested on COX-2 and VEGF activation and prostaglandin (PG)E(2) release. METHODS: RF/6A cells were subjected to hypoxia for 1 and 3 hours, at which times RNA and proteins were isolated. Potential AP-1, hypoxia-inducible factor (HIF)-1 and NF-kappaB DNA-binding sites were identified using DNA sequence search algorithms and were analyzed using gel-shift assay. COX-2 and VEGF RNA, protein, and PGE(2) levels were quantified by RT-PCR, Western analysis, and enzyme immunoassay, respectively. Tubular morphogenesis was analyzed with phase-contrast imaging microscopy. RESULTS: Nuclear AP-1, HIF-1 and NF-kappaB promoter DNA binding increased 1.5-, 4-, and 3-fold, respectively, after 1 hour of hypoxia. COX-2 RNA was elevated five- and fourfold after 1 and 3 hours of hypoxia, respectively. VEGF RNA and protein abundance lagged behind COX-2 induction but were each increased two- to threefold 3 hours after hypoxia. CGP43182 was found to inhibit NF-kappaB DNA binding, COX-2 and VEGF gene expression, PGE(2) release, and hypoxia-induced tubular morphogenesis. CONCLUSIONS: Maximum HIF-1 and NF-kappaB DNA binding immediately before COX-2 expression suggests that these TFs are important regulators of COX-2 induction in hypoxic RF/6A cells. IL-1beta emulated AP-1, HIF-1, and NF-kappaB DNA binding during hypoxia and may be a novel cytokine trigger for NV. CGP43182 appears to be an effective inhibitor of NV. VEGF expression appears to be regulated through dual interdependent mechanisms involving HIF-1 directly and indirectly through NF-kappaB-mediated COX-2 expression and PGE(2) production.

Peripapillary scleral thickness in perfusion-fixed normal monkey eyes.

PURPOSE: To characterize the thickness of the peripapillary sclera in perfusion-fixed normal monkey eyes so as to build accurate computational models of intraocular pressure (IOP)-related stress and strain within these tissues. METHODS: Nine rhesus monkeys were perfusion fixed, each with one normal eye set to an IOP of 10 mm Hg by manometer. A 6-mm-diameter specimen containing the optic nerve head and peripapillary sclera was trephined from each scleral shell and cut into 4-microm serial sagittal sections across the scleral canal opening, either horizontally (four eyes) or vertically (five eyes). The thickness of the peripapillary sclera was measured on every 24th section at 100-microm intervals from the posterior scleral canal opening (PSCO) to the peripheral edge of the specimen. The data were pooled by quadrant (superior, inferior, nasal, and temporal), regions within each quadrant, and distance from the PSCO, overall and for individual eyes, and subjected to analysis of variance. RESULTS: In terms of distance from the PSCO, the peripapillary sclera was thinnest nearest the PSCO (201 microm, nasal; 201 microm, temporal; 240 microm, inferior; 249 microm, superior), thickened progressively to a maximum in the midperiphery approximately 600 to 1000 microm from the PSCO (326 microm, nasal; 415 microm, superior; 420 microm, temporal; 422 microm, inferior), and thinned again peripherally in all quadrants. The peripapillary sclera was thinner in the nasal quadrant when compared with the other quadrants superiorly, inferiorly, and temporally (central region means of 291 microm, nasal; 369 microm, superior; 372 microm, inferior; and 369 microm, temporal; P < 0.0001). CONCLUSIONS: In the normal monkey eye, peripapillary scleral thickness varies significantly with distance from the posterior scleral canal opening and is thinner in the nasal quadrant than in the other quadrants. These differences are substantial and are likely to affect the magnitude of IOP-related stress and strain within these tissues for a given level of IOP.

Corneal pathogenesis of Staphylococcus aureus strain Newman.

PURPOSE: To determine the pathogenic role of gamma- and alpha-toxin in a rabbit model of Staphylococcus aureus keratitis. METHODS: S. aureus strains Newman (expressing gamma-toxin), Newman Delta(hlg) (deficient in gamma-toxin), Newman Delta(hlg)/pCU1 hlg(+) (chromosomal gamma-toxin-deficient mutant rescued by a plasmid encoding gamma-toxin), and Newman Delta(hla) (alpha-toxin-deficient) were intrastromally injected into rabbit corneas. Eyes were scored by slit lamp examination (SLE), and bacterial colony-forming units (CFU) per cornea were determined at 15, 20, and 25 hours after infection. Histologic examination of corneas was performed. Rabbits were immunized against alpha-toxin and subsequently challenged with S. aureus strain Newman. Western blot analyses of culture supernatants were performed to detect alpha-toxin production. RESULTS: All strains grew equivalently, producing approximately 7 log CFU per cornea at 25 hours after infection. SLE scores at 20 and 25 hours after infection revealed that strains Newman Delta(hlg) and Newman Delta(hla), although virulent, caused significantly less ocular damage and inflammation than their parent or the gamma-toxin genetically rescued strain (P

Long-term vision results measured with Teller Acuity Cards and a new Light Perception/Projection Scale after management of late stages of retinopathy of prematurity.

OBJECTIVES: To report visual acuity (VA) measured by Teller Acuity Cards (TACs) and a new Light Perception/Projection (LPP) Scale in infants with regressed or treated stage 3, 4, or 5 retinopathy of prematurity (ROP), and to compare VA in eyes that underwent successful vitreoretinal surgery for stage 5 ROP with eyes with persistent retinal detachment. METHODS: Nineteen infants (35 eyes) underwent VA testing using TACs and the LPP scale. The correlation between the methods was determined. Comparisons in VA scores were made in eyes by stage of ROP at the first examination and retinal status at the end of follow-up and between eyes with successful surgical reattachment and persistent retinal detachment. RESULTS: Scores obtained with the LPP scale and TACs were highly correlated (Spearman rank-order correlation coefficient, 0.92; P<.001). Visual acuity was better in eyes with retinal attachment at the end of follow-up than in eyes with retinal detachment whether the ROP stage at first examination was 4A (n = 6), 4B (n = 16), or 5 (n = 6). In eyes that progressed to stage 5 ROP and had successful surgical retinal reattachment (n = 16), both methods of measurement yielded better visual function than in eyes with persistent retinal detachment. The LPP scale provided scores for eyes without quantifiable grating acuity determined with TAC. CONCLUSIONS: The LPP scale scores were correlated with TAC scores in infants with stages 3, 4, and 5 ROP. Surgical retinal reattachment in stage 5 ROP resulted in better visual function. The LPP scale may be useful in measuring low vision in infants without quantifiable grating acuity and with later stages of ROP.

Using dependency/association rules to find indications for computed tomography in a head trauma dataset.

Analysis of a clinical head trauma dataset was aided by the use of a new, binary-based data mining technique, termed Boolean analyzer (BA), which finds dependency/association rules. With initial guidance from a domain user or domain expert, the BA algorithm is given one or more metrics to partition the entire dataset. The weighted rules are in the form of Boolean expressions. To augment the analysis of the rules produced, we applied a probabilistic interestingness measure (PIM) to order the generated rules based on event dependency, where events are combinations of primed and unprimed variables. Interpretation of the dependency rules generated on the clinical head trauma data resulted in a set of criteria that identified minor head trauma patients needing computed tomography (CT) scans. The BA criteria contained fewer variables than were found using recursive partitioning of Chi-square values (five variables versus seven variables, respectively). The BA five-variable criteria set was more sensitive but less specific than the seven-variable Chi-square criteria set. We believe that the BA method has broad applicability in the medical domain, and hope that this paper will stimulate other creative applications of the technique.

Long-term study of accommodative esotropia.

PURPOSE: Previous studies of accommodative esotropia have been hampered by bias-prone methods of data collection and analysis and by small sample size. The studies have conflicting conclusions, causing uncertain results. This study aims to determine long-term results of standard treatment of accommodative esotropia and identify predictors of outcome, while minimizing bias in data collection and analysis, using the largest possible sample size. METHODS: A research assistant collected data from all files of a large, long-established pediatric ophthalmology practice (M.M.P.). The assistant was given standardized collection forms that allowed inclusion of all patient data points over all visits. The assistant was masked as to study goals. She was instructed to include any patient with esotropia who had been prescribed glasses during treatment. Descriptive terms were converted to code numbers. A second, similarly masked research assistant entered data into a computerized database. Criteria for patient inclusion were designed to conform to earlier studies by I.H.L. and M.M.P. and were implemented by computer. RESULTS: The database totaled 1,307 patients (747,717 data points). Of these, 354 qualified for this analysis. A greater difference between near and distance esodeviation (AC/A relationship) correlated with a higher rate of deterioration of accommodative esotropia control (P<.0001). Deterioration also positively correlated with earlier age at onset, inferior oblique overaction, and amblyopia. CONCLUSIONS: This study agrees with our previous findings that a high AC/A relationship increases the likelihood of deterioration of accommodative esotropia, thus confirming the integrity of the database. This unique, unbiased dataset will be used for future analyses of esotropia.

Modulation of immune signaling, bacterial clearance, and corneal integrity by toll-like receptors during streptococcus pneumoniae keratitis.

PURPOSE: Bacterial keratitis, without effective antimicrobial treatment, leads to poor patient prognosis. Even after bacterial clearance, the host inflammatory response can contribute to corneal damage. Though Streptococcus pneumoniae (pneumococcus) is a common cause of bacterial keratitis, the role of host innate immunity during pneumococcal keratitis is not well characterized. This study investigated the role of Toll-like receptors (TLRs) during pneumococcal keratitis. MATERIALS AND METHODS: C57BL/6, as well as TLR2(-/-) and TLR4(-/-) mice, were infected with S. pneumoniae, and infected corneas were examined for 21 days. Quantitative real-time reverse-transcriptase polymerase chain reaction was performed using primers for genes involved in the inflammatory response and TLR signaling. Bacterial survival and leukocyte invasion were examined over a 72-h period. RESULTS: The corneal expression of TLR2, TLR4, and other inflammatory genes was increased at 72 h post-infection (p.i.) compared to uninfected C57BL/6 scratch controls. TLR2(-/-) mice showed a significant increase in bacterial survival at 24 h p.i. likely due to decreased neutrophil infiltration; however, after Day 5 p.i. observed clinical scores of TLR2(-/-) and C57BL/6 mice were not significantly different. In contrast, permanent corneal damage was observed for TLR4(-/-) mice over 21 days. Initially, both TLR(-/-) mouse strains exhibited lower expression levels in many immune genes, but returned to similar or elevated levels compared to C57BL/6 mice by 72 h p.i. CONCLUSIONS: TLR2 and TLR4 are involved in the response to pneumococcal keratitis and TLR2 may aid in bacterial clearance by recruitment of neutrophils to the cornea, whereas TLR4 may be necessary to modulate the immune response to limit cellular damage.

Upregulation of mouse genes in HSV-1 latent TG after butyrate treatment implicates the multiple roles of the LAT-ICP0 locus.

PURPOSE: To determine host response by gene expression in HSV-1 latent trigeminal ganglia (TG) after sodium butyrate (NaBu) treatment. METHODS: Corneas of 6-week-old female BALB/c mice were scarified and inoculated with HSV-1 17Syn(+) (high phenotypic reactivator) or its mutant 17ΔPst(LAT(-)) (low phenotypic reactivator) at 10(4) plaque-forming units/eye. NaBu-induced viral reactivation was by intraperitoneal (IP) administration at postinfection (PI) day 28, followed by euthanasia after 1 hour. NaBu-treated, uninfected mice served as the control. The resultant labeled cRNA from TG isolated total RNA was hybridized to gene microarray chips containing 14,000 mouse genes. Quantitative real-time PCR was performed to confirm gene expression. RESULTS: Differential induction of gene expression between 17Syn(+) and its mutant 17ΔPst(LAT(-)) was designated as NaBu-induced gene expression and yielded significant upregulation of 2- to 16-fold of 0.4% (56/14,000) host genes probed, comprising mainly nucleosome assembly and binding, central nervous system structural activity, hormonal activity, and signaling activity. Approximately 0.2% (24/14,000) of the host genes, mainly of the same functional categories were downregulated 3- to 11-fold. Immune activity was minor in comparison to our reports on gene expression during latency and heat stress induction. Euchromatin analysis revealed that the LAT-ICP0 locus is amenable to the effects of NaBu. Histone activity was detected by early transcription of histone cluster 2 H2be (Hist2h2be). CONCLUSIONS NaBu-induced reactivation of HSV-1 is twofold: drug action involving significant moderation of specific host epigenetic changes and failure to elicit or suppress immune activity at the early time point of 1 hour.