The practical and educational value of scleral buckling with chandelier illumination

PURPOSE

To compare the surgical results in cases of primary rhegmatogenous retinal detachments between standard scleral buckling (SSB) and scleral buckling with chandelier illumination (SBC) and to analyse the differences in SBC surgical results between an experienced ophthalmologist and inexperienced ophthalmologists.

METHODS

Consecutive surgical case series of 155 eyes that underwent scleral buckling were retrospectively reviewed and divided into four groups: SSB performed by an experienced ophthalmologist (n = 54), SBC performed by an experienced ophthalmologist (n = 52), SBC performed by inexperienced ophthalmologists (n = 40) and SSB performed by inexperienced ophthalmologists (n = 9). Then, these four groups were compared.

RESULTS

No significant differences were observed between SSB and SBC procedures both performed by the experienced ophthalmologist with regard to demographics, preoperative findings, contents of the surgery, intraoperative complications, retinal reattachment, postoperative findings and postoperative complications. Between SBC performed by the experienced ophthalmologist and SBC performed by the inexperienced ophthalmologists, no significant differences were found regarding intraoperative complications, retinal reattachment, postoperative findings and postoperative complications. Between SSB and SBC procedures both performed by the inexperienced ophthalmologist, a significant difference was found regarding intraoperative complications.

CONCLUSION

There were no significant differences in surgical results between SSB and SBC when both were performed by the experienced ophthalmologist. In addition, the surgical results were equal between the experienced ophthalmologist and the inexperienced ophthalmologist as far as SBC was concerned. Learning scleral buckling skills by using SBC is a reasonable course of action for inexperienced ophthalmologists.

Visual acuity after intravitreal ranibizumab with and without laser therapy in the treatment of macular edema due to branch retinal vein occlusion: a 12-month retrospective analysis

AIM

To identify factors contributing to visual improvement after treatment of macular edema (ME) secondary to branch retinal vein occlusion (BRVO), and to assess the interaction between laser therapy and intravitreal ranibizumab (IVR).

METHODS

We retrospectively reviewed the medical records of patients who had been treated for BRVO-related ME at our hospital. Records were traceable for at least 12mo, and evaluated factors included age, sex, medical history, smoking history, treatment methods, foveal hemorrhage, and change in visual acuity. Treatments included laser therapy, IVR, sub-Tenon's capsule injection of triamcinolone (STTA), a combination, or no intervention. Multivariate logistic regression analysis and interaction terms were used to assess the clinical efficacy of the treatments, and odds ratios (OR) and 95% confidence intervals (CI) were calculated.

RESULTS

Seventy-three patients (34 men, 39 women; 73 eyes) with a mean age of 69.4±12.1y were included. Patients who underwent IVR monotherapy, laser monotherapy, and STTA+laser had significantly higher best corrected visual acuity at 12mo compared to baseline (P<0.001, <0.001, and 0.019, respectively). Logistic regression analysis without interaction terms found that IVR was a significant visual acuity recovery factor (adjusted OR: 3.89, 95%CI: 1.25-12.1, P=0.019). Adjusted OR using an interaction model by logistic regression was 16.6 (95%CI: 2.54-108.47, P=0.003) with IVR treatment, and 8.25 (95%CI: 1.34-50.57, P=0.023) with laser treatment. No interaction was observed (adjusted OR: 0.07, 95%CI: 0.01-0.75, P=0.029).

CONCLUSION

IVR contributes to improvements in visual acuity at 12mo in ME secondary to BRVO. No interaction is observed between laser therapy and IVR treatments.

Effects of the Numbers and the Shapes of Venting Slits on Intraocular Pressure after Baerveldt Glaucoma Drainage Implant

Purpose: Venting slits are widely used as an effective method to avoid the high intraocular pressure (IOP) phase immediately after the implantation of non-valved glaucoma drainage devices. However, there have been no detailed reports comparing the types of needles used and the numbers of slits made. In this study we investigated the effects of different needle types and the number of venting slits. Methods: IOP was measured using a Keyence NR-600 transducer connected to the limbus of a pig eye with a 27G needle. A microsyringe pump was also connected to the corneal limbus using a 27 G needle to make a continuous perfusion system at the rate of 200 μl/hr. The silicone tube of a Baerveldt glaucoma drainage implant (BG101-350) was ligated near the plate and then implanted in the anterior chamber of the pig eye. The tube was covered with scleral tissue of another pig eye after 1 or 3 venting slits were created in the middle of the outer diameter using different types of needles (7-0 Vicryl®, 7-0 PDSⅡ®, 5-0 PDSⅡ®, 3-0 PDS Plus®). IOP measurement was started from 50 mmHg and then we monitored the chronological changes of IOP for 15 minutes. Results: The IOPs at 15 minutes after continuous perfusion with the venting slits made using 7-0 Vicryl needles were 29.0 ± 2.5 mmHg (1 slit) and 23.1 ± 8.3 mmHg (3 slits). The IOPs were 23.1 ± 3.1 mmHg and 23.5 ± 4.7 mmHg with 7-0 PDS needles (1 slit and 3 slits, respectively), 21.8 ± 2.2 mmHg and 20.8 ± 4.3 mmHg with 5-0 PDS needles (1 slit and 3 slits, respectively), and with 3-0 PDS needles they were 12.2 ± 3.0 mmHg for one slit and 13.2 ± 3.5 mmHg for 3 slits. Conclusions: Usage of a round (PDS) needles produces more predictable IOP than a spatulated (Vicryl) needle.

Visual impairment as an independent risk factor for falls in hospitalized patients

OBJECTIVE

To investigate the association between visual impairment and the risk of falls in hospitalized patients.

DESIGN

Individually matched case-control study.

METHODS

The medical records of patients who fell while hospitalized at Juntendo Tokyo Koto Geriatric Medical Center (JTKGMC) from January to December 2014 were reviewed retrospectively. Among them, 36 patients who were recorded as visiting the Ophthalmology Outpatient Clinic from 1 year before to 1 year after the fall were included as cases. As the control subjects, 36 individually matched patients were chosen who were hospitalized in the same beds in the same hospital wards. Visual impairment and blindness were defined according to U.S. criteria. Conditional logistic regression analysis was used for both univariate and multivariate analyses. Based on previous reports, multivariate analysis was performed with adjustment for age, sex, a history of falls, and use of walking aids. This study was approved by the institutional review board of JTKGMC and was performed according to the tenets of the Declaration of Helsinki.

RESULTS

The crude odds ratio (OR) for visual impairment was 6.0 (95% confidence interval [CI]: 0.72-49.83). For a history of falls and use of walking aids, the crude OR (95% CI) was 2.5 (0.97-6.44) and 2.8 (0.88-8.64), respectively. After adjustment for age, sex, a history of falls, and use of walking aids, the association between falls and visual impairment was significant (OR: 13.9; 95% CI: 1.0004-194.41).

CONCLUSION

These findings suggest that visual impairment could be an independent risk factor for falls among hospitalized patients.

The Effect of Cumulative Dissipated Energy on Changes in Intraocular Pressure After Uncomplicated Cataract Surgery by Phacoemulsification

PURPOSE

To investigate the association between ultrasound energy, expressed as cumulative dissipated energy (CDE), and changes in intraocular pressure (IOP) after uncomplicated cataract surgery by phacoemulsification.

METHODS

In this prospective study, nonglaucomatous subjects underwent cataract surgery by phacoemulsification. IOP was compared by clustered linear regression at 4 separate time-points: preoperative, 1 day, 1 month, and 3 months after cataract surgery. Changes in the IOP were evaluated as a function of CDE using univariate and multivariate clustered linear regression models, which adjusted for sex, ethnicity, age, axial length, spherical equivalent, mean preoperative Shaffer gonioscopy grade of all 4 quadrants, cataract grade, preoperative IOP, central corneal thickness, and use of both eyes in the same subject.

RESULTS

One hundred sixty-one eyes (89 Asian, 49 white, 12 African, and 11 Hispanic) from 116 nonglaucomatous subjects were analyzed. The 161 eyes included 81 right and 80 left eyes. The 89 Asian eyes included 46 Chinese, 35 Filipino, and 8 Vietnamese. Preoperative IOP was 14.9±3.2 mm Hg. Postoperative IOP significantly increased to 16.0±4.9 mm Hg at 1 day (P=0.037) and decreased to 12.4±3.1 and 12.3±3.0 mm Hg at 1 and 3 months, respectively (both P<0.0001). IOP changes at 1 day, 1 month, and 3 months did not demonstrate significant associations with CDE measurements in either univariate or multivariate clustered linear regression analyses (all P>0.05).

CONCLUSIONS

The amount of ultrasound energy delivered to the eye during phacoemulsification, expressed as CDE, was not associated with postoperative changes in IOP.

Chest Imaging with Dual-Energy Subtraction Digital Tomosynthesis

Dual-energy subtraction digital tomosynthesis with pulsed X-ray and rapid kV switching was used to examine calcifications in pulmonary lesions. The digital tomosynthesis system used included a conventional fluororadiographic TV unit with linear tomographic capabilities, a high resolution videocamera, and an image processing unit. Low-voltage, high-voltage, and soft tissue subtracted or bone subtracted tomograms of any desired layer height were reconstructed from the image data acquired during a single tomographic swing. Calcifications, as well as their characteristics and distribution in pulmonary lesions, were clearly shown. The images also permitted discrimination of calcifications from dense fibrotic lesions. This technique was effective in demonstrating calcifications together with a solitary mass or disseminated nodules.

Digital Image Processing to Remove Blur from Linear Tomography of the Lung

We have studied digital image processing methods to reduce blur in linear tomography of the lung performed with the Fuji computed radiography (FCR) system. One-dimensional unsharp (blur) mask filtering in the direction of tomographic movement was found to be effective in reducing blur. The appearance of the processed tomograms varied depending largely on the properties of the unsharp mask filters applied. With regard to the spatial frequency response of the filter, a high mid-frequency response and a low low-frequency response of the tomographic image data was most effective in obtaining high image quality tomograms. When the standard 2-dimensional unsharp mask technique of the FCR system was additionally applied to the one-dimensional unsharp mask processed tomogram, the clarity of the tomogram was further enhanced. These observations may also be helpful when considering image processing to obtain diagnostically informative digital radiography.

Hypothyroidism and Glaucoma in The United States

PURPOSE

To investigate the association between hypothyroidism and glaucomatous disease.

METHODS

This cross-sectional study included all subjects above the age of 40 years from two nationwide surveys: the 2008 National Health Interview Survey (NHIS) as well as the 2007 and 2008 National Health and Nutrition Examination Survey (NHANES). The presence or absence of glaucoma, thyroid disease and other demographic and health-related information including comorbidities was ascertained via interview. Blood samples were collected from NHANES subjects and analyzed for thyrotropin (TSH).

RESULTS

A total of 13,599 and 3,839 NHIS and NHANES participants respectively were analyzed to assess for a possible relationship between self-reported glaucoma, and self-reported hypothyroidism as well as self-reported thyroid disease. The unadjusted odds ratio (OR) for NHIS showed a significant association between self-reported glaucoma and self-reported hypothyroidism (OR 1.46, 95% confidence interval [CI] 1.07-1.99). Multivariate logistic regression analysis adjusted for age, gender, race, comorbidities, and health-related behavior, however, showed no association between self-reported glaucoma and hypothyroidism or thyroid disease in both surveys (OR 1.60, 95%CI 0.87-2.95 for NHIS; OR 1.05, 95%CI 0.59-1.88 for NHANES).

CONCLUSION

A previously reported association between hypothyroidism and glaucomatous disease was not confirmed in two large U.S. health survey populations. While such an association was noted in the univariate analysis for the NHIS survey, such a relationship was not found in the multivariate analysis after adjustment for potential confounding variables.

Cotton-wool-like bioactive glasses for bone regeneration

Inorganic sol-gel solutions were electrospun to produce the first bioactive three-dimensional (3-D) scaffolds for bone tissue regeneration with a structure like cotton-wool (or cotton candy). This flexible 3-D fibrous structure is ideal for packing into complex defects. It also has large inter-fiber spaces to promote vascularization, penetration of cells and transport of nutrients throughout the scaffold. The 3-D fibrous structure was obtained by electrospinning, where the applied electric field and the instabilities exert tremendous force on the spinning jet, which is required to be viscoelastic to prevent jet break up. Previously, polymer binding agents were used with inorganic solutions to produce electrospun composite two-dimensional fibermats, requiring calcination to remove the polymer. This study presents novel reaction and processing conditions for producing a viscoelastic inorganic sol-gel solution that results in fibers by the entanglement of the intermolecularly overlapped nanosilica species in the solution, eliminating the need for a binder. Three-dimensional cotton-wool-like structures were only produced when solutions containing calcium nitrate were used, suggesting that the charge of the Ca(2+) ions had a significant effect. The resulting bioactive silica fibers had a narrow diameter range of 0.5-2μm and were nanoporous. A hydroxycarbonate apatite layer was formed on the fibers within the first 12h of soaking in simulated body fluid. MC3T3-E1 preosteoblast cells cultured on the fibers showed no adverse cytotoxic effect and they were observed to attach to and spread in the material.

Enhanced polarization of hydroxyapatite using the design concept of functionally graded materials with sodium potassium niobate

The present work aims to enhance the electrical activities of hydroxyapatite (HA) without affecting its bioactivity through the development of functionally graded materials (FGM) using biocompatible sodium potassium niobate (NKN) piezoelectrics as an intermediary layer.

Comparison of anterior segment morphology following prophylactic laser peripheral iridotomy in Caucasian and Chinese eyes

BACKGROUND

To compare anterior segment biometric parameters between Caucasians and Chinese before and after laser peripheral iridotomy.

DESIGN

Prospective clinical cohort study.

PARTICIPANTS

Caucasian and Chinese primary angle-closure suspects.

METHODS

Anterior segment optical coherence tomography images captured before and after laser peripheral iridotomy were analysed to measure anterior segment biometric parameters. Paired Student's t-tests were used for within-ethnic group comparisons. Univariate and linear mixed-effect regression models were used for between-ethnic group comparisons.

MAIN OUTCOME MEASURES

Angle opening distance, angle recess area, iris thickness, iris curvature, anterior chamber area, anterior chamber volume and anterior chamber width.

RESULTS

Caucasians had significantly greater preoperative angle recess area, anterior chamber width, and iris curvature and lower preoperative iris thickness compared to Chinese (P < 0.05). Significant postoperative increases in angle opening distance, angle recess area, anterior chamber area, anterior chamber volume, and anterior chamber width along with significant postoperative decrease in iris curvature were observed within both ethnic groups (P < 0.05). However, the amount of laser peripheral iridotomy-induced changes in angle opening distance, angle recess area, anterior chamber area, anterior chamber volume, anterior chamber width, and iris curvature did not differ between the two ethnic groups (P < 0.05).

CONCLUSION

Both Caucasian and Chinese demonstrated opening of anterior chamber angle width, expansion of anterior chamber dimensions, and flattening of iris convexity after laser peripheral iridotomy. Although certain aspects of anterior segment anatomy differed between Caucasians and Chinese preoperatively, they did not translate into significant ethnic differences in the amount of laser peripheral iridotomy-induced changes in the anterior segment biometric parameters.

Correlation between central corneal thickness and myopia in Taiwan

The aim of the study was to explore the correlation between central corneal thickness (CCT) and the degree of myopia in Taiwanese adults. A total of 528 individuals were enrolled to undergo myopic laser refractive surgery from January 2004 to December 2006. Preoperative CCT was measured using the Orbscan corneal topography system and refractive status was determined by cycloplegic spherical equivalent. The relationship between CCT and refractive error was investigated by interindividual and intraindividual analyses. Participants had a mean age of 34.8 ± 7.3 years, and 79.9% were female. The mean refractive error was -7.27 ± 2.96 diopters and the mean CCT measurement was 560 ± 35 μm. CCT revealed that there was no association with age. However, CCT was significantly (p = 0.012) less in females than in males. The CCT also showed no significant association with refractive error (p = 0.49). Among the 67 participants with myopic anisometropia, the mean difference between both eyes was 3.09 ± 1.06 diopters. There was no association between the intereye CCT difference and refractive error (p = 0.57). The results remained the same after adjusting for age and sex. In conclusion, there was no correlation between CCT and the degree of myopia among adults in Taiwan. These data might contribute to the ongoing discussion about the role of CCT in the higher incidence of development and progression of glaucoma in myopic individuals.

Ethnic variation in optic disc size by fundus photography

PURPOSE

To compare optic disc size among Caucasian, Chinese, African, Filipino and Hispanic subjects recruited from a university-based general ophthalmology clinic.

METHODS

In this retrospective cross-sectional study, optic disc size was calculated from fundus photographs. Differences in age, sex and spherical equivalent among the ethnic groups were examined with either Kruskal--Wallis test or Chi-square test. Ethnic differences in optic disc size were evaluated with linear mixed-effects regression models that adjusted for age, sex, spherical equivalent, glaucoma status, lens status and use of both eyes in the same subject.

RESULTS

Five hundred and seventy-four eyes of 305 subjects were analyzed. The mean and standard deviation of the optic disc size were 2.16 ± 0.41 mm(2) for Caucasian, 2.30 ± 0.56 mm(2) for Chinese, 2.31 ± 0.41 mm(2) for Filipino, 2.38 ± 0.40 mm(2) for African and 2.40 ± 0.38 mm(2) for Hispanic subjects. Age and spherical equivalent differed among the ethnic groups by Kruskal--Wallis test (p < 0.05). Sex differed among the ethnic groups by Chi-square test (p < 0.05). Ethnic differences in optic disc size were not observed among African, Hispanic, Filipino and Chinese subjects in linear mixed-effects regression analyses (p > 0.05). However, Caucasian differed from the other ethnicities in linear mixed-effects regression analyses (p < 0.05).

CONCLUSIONS

Optic disc size was significantly smaller in Caucasian compared to the other ethnic groups. Optic disc size differences among non-Caucasian ethnic groups were not significant.

Association between baseline angle width and induced angle opening following prophylactic laser peripheral iridotomy

PURPOSE

To evaluate the association between baseline angle width and laser peripheral iridotomy (LPI)-induced opening of the anterior chamber angle.

METHODS

Anterior segment optical coherence tomography images captured before and after LPI were analyzed to determine the angle opening distance at 250 μm (AOD250), 500 μm (AOD500), and 750 μm (AOD750) from the scleral spur; trabecular-iris space area at 500 μm (TISA500) and 750 μm (TISA750) from the scleral spur; angle recess area at 750 μm (ARA750) from the scleral spur; and trabecular-iris angle (TIA). Differences in preoperative and postoperative measurements for the anterior chamber angle width parameters were compared by paired Student's t-tests. Univariate and linear mixed-effects regression models were used to examine the association between baseline and LPI-induced opening of anterior chamber angle width parameters.

RESULTS

Eighty-four eyes of 52 primary angle closure suspects were included in the analysis. AOD250, AOD500, AOD750, TISA500, TISA750, ARA750, and TIA significantly increased following LPI by paired Student's t-tests (all P < 0.0001). Lower baseline measurements were significantly associated with greater postoperative opening in all anterior chamber angle width parameters in both univariate and linear mixed-effects regression analyses (all P < 0.05).

CONCLUSIONS

Our results showed significant opening of the anterior chamber angle width after LPI and demonstrated an inverse association between baseline and LPI-induced opening of the anterior chamber angle width, such that eyes with a more crowded anterior chamber angle undergoing LPI had a greater magnitude of increase in anterior chamber angle width after the procedure.

Trabecular meshwork length in men and women by histological assessment

PURPOSE

To evaluate the length of the trabecular meshwork (TM) from the scleral spur (SS) to Schwalbe's line (SL) and assess the detectability of the SS in histopathology specimens.

METHODS

This study included 158 angle images from 79 cross-sectional slides derived from eyes enucleated for melanoma. The slides were stained with hematoxylin-eosin (HE) or periodic acid schiff (PAS). Two ophthalmologists evaluated the TM length by using the slides stained with HE to assess the interobserver reproducibility. For intraobserver reproducibility, the first observer assessed 79 images in a different session. Also, 30 images that were randomly selected for PAS stain were evaluated to assess the agreement of the measurements between HE and PAS staining. Interclass correlation coefficients (ICC) were calculated to evaluate reproducibility of measurements. The images were also evaluated for detectability of the scleral spurs.

RESULTS

Among the 79 included subjects, 40 were male and 39 were female. The average trabecular meshwork length was 694.9 ± 109.0 µm in the male group and 713.2 ± 106.9 µm in the female group (p = 0.29). Intraobserver and interobserver ICC were 0.89 and 0.62, respectively. ICC for agreement between HE and PAS was 0.89. Among the 158 angles graded, the first observer graded 40 images (25.3%) and the second observer graded 45 (28.5%) as difficult to identify the scleral spur.

CONCLUSIONS

There was no statistically significant difference between the average trabecular meshwork length in men and women. Among the angles evaluated, 25.3-28.5% were graded as difficult to identify the scleral spur.

Comparison of optic nerve head topography and retinal nerve fiber layer in eyes with narrow angles versus eyes from a normal open angle cohort - a pilot study

PURPOSE

To compare the optic nerve head (ONH) and retinal nerve fiber layer (RNFL) in eyes with narrow angles and normal intraocular pressure (IOP) to normal control eyes.

MATERIALS AND METHODS

A total of 70 eyes of 52 subjects with narrow angles and 40 eyes of 34 normal subjects were enrolled. Narrow angle eyes were defined as the following: (i) the pigmented trabecular meshwork was not visible for ≥ 180° on gonioscopy, (ii) untreated IOP ≤ 21 mmHg, (iii) no peripheral anterior synechiae (PAS) was observed, and (iv) optic discs were without glaucomatous changes, defined as neuroretinal rim thinning, focal notching, disc hemorrhages, or focal RNFL defects. ONH and peripapillary RNFL imaging were obtained with Heidelberg Retina Tomograph (HRT II) and Fourier-domain optical coherence tomography (RTVue OCT).

RESULTS

No significant difference was found in mean age between the two groups (p = 0.06), but the narrow angle group had significantly more women (p = 0.04). The narrow angle group had significantly higher IOP and smaller mean angle width (both p < 0.001). Vertical cup-to-disc ratio (VCDR) was significantly larger in the narrow angle group (p = 0.02). In visual field (VF) results, the mean deviation (MD) was significantly lower and pattern standard deviation (PSD) was significantly higher in the narrow angle group (both p < 0.001). After adjusting for disc area, the RNFL thickness of the inferior-temporal region was significantly thinner in the narrow angle group (135 ± 21.7 µm) compared with normal group (149 ± 22.1 µm, p < 0.01). This finding remained significant after Bonferroni correction for multiple comparisons. Smaller angle width was a significant predictor of RNFL thinning in the inferior-temporal region (p < 0.001).

CONCLUSION

These data suggest that eyes with narrow angles may develop glaucomatous optic nerve damage in the absence of IOP elevation during office hours.

Vaterite deposition on biodegradable polymer foam scaffolds for inducing bone-like hydroxycarbonate apatite coatings

Hydroxycarbonate apatite (HCA) coatings on the surface of bioresorbable materials for bone tissue engineering scaffolds were produced using macroporous poly(DL-lactide) (PDLLA) foams impregnated by calcium carbonate in vaterite crystalline form. Stable and homogeneous vaterite deposition on PDLLA foams was achieved using a slurry dipping technique. In vitro studies in simulated body fluid (SBF) were performed to induce formation of (HCA) on the surface of vaterite/PDLLA composite foams. HCA was detected after immersion of foams in SBF for 7 days. Hence, depositing vaterite on materials followed by immersion in SBF is confirmed to induce HCA coatings on the surface of the material. The HCA coated, bioactive and resorbable PDLLA foams are intended for use as bone tissue engineering scaffolds.

Phase-specific gene expression underlying morphological adaptations of the dimorphic human pathogenic fungus, Coccidioides posadasii

Coccidioides posadasii is a dimorphic fungal pathogen that grows as a filamentous saprobe in the soil and as endosporulating spherules within the host. To identify genes specific to the pathogenic phase of Co. posadasii, we carried out a large-scale study of gene expression in two isolates of the species. From the sequenced Co. posadasii genome, we chose 1,000 open reading frames to construct a 70-mer microarray. RNA was recovered from both isolates at three life-cycle phases: hyphae, presegmented spherules, and spherules releasing endospores. Comparative hybridizations were conducted in a circuit design, permitting comparison between both isolates at all three life-cycle phases, and among all life-cycle phases for each isolate. By using this approach, we identified 92 genes that were differentially expressed between pathogenic and saprobic phases in both fungal isolates, and 43 genes with consistent differential expression between the two parasitic developmental phases. Genes with elevated expression in the pathogenic phases of both isolates included a number of genes that were involved in the response to environmental stress as well as in the metabolism of lipids. The latter observation is in agreement with previous studies demonstrating that spherules contain a higher proportion of lipids than saprobic phase tissue. Intriguingly, we discovered statistically significant and divergent levels of gene expression between the two isolates profiled for 64 genes. The results suggest that incorporating more than one isolate in the experimental design offers a means of categorizing the large collection of candidate genes that transcriptional profiling typically identifies into those that are strain-specific and those that characterize the entire species.

Subaru Telescope Observations of Deep Impact

The impact cratering process on a comet is controversial but holds the key for interpreting observations of the Deep Impact collision with comet 9P/Tempel 1. Mid-infrared data from the Cooled Mid-Infrared Camera and Spectrometer (COMICS) of the Subaru Telescope indicate that the large-scale dust plume ejected by the impact contained a large mass (approximately 10(6) kilograms) of dust and formed two wings approximately +/-45 degrees from the symmetric center, both consistent with gravity as the primary control on the impact and its immediate aftermath. The dust distribution in the inner part of the plume, however, is inconsistent with a pure gravity control and implies that evaporation and expansion of volatiles accelerated dust.

Deep Impact: observations from a worldwide Earth-based campaign

On 4 July 2005, many observatories around the world and in space observed the collision of Deep Impact with comet 9P/Tempel 1 or its aftermath. This was an unprecedented coordinated observational campaign. These data show that (i) there was new material after impact that was compositionally different from that seen before impact; (ii) the ratio of dust mass to gas mass in the ejecta was much larger than before impact; (iii) the new activity did not last more than a few days, and by 9 July the comet's behavior was indistinguishable from its pre-impact behavior; and (iv) there were interesting transient phenomena that may be correlated with cratering physics.

Carbonate-containing hydroxyapatite derived from calcium tripolyphosphate gel with urea

Carbonate containing hydroxyapatite (CO3HAp) is one of the candidate materials as a bioresorbable bone substitute. In the present work, CO3HAp was efficiently prepared by a hydrothermal treatment of calcium tripolyphosphate gel with urea at 140 degrees C for 24 h. Chemical potential plots of the CO3HAp for estimation of its dissolution behavior suggested that the CO3HAp is more soluble than hydroxyapatite (HAp) and is as soluble as octacalcium phosphate (OCP) and/or beta -tricalcium phosphate (TCP). This material is expected to be applied to bioresorbable materials such as bone fillers.

Identification of a large cluster of coiled coil-nucleotide binding site--leucine rich repeat-type genes from the Rps1 region containing Phytophthora resistance genes in soybean

Fifteen Rps genes confer resistance against the oomycete pathogen Phytophthora sojae, which causes root and stem rot disease in soybean. We have isolated a disease resistance gene-like sequence from the genomic region containing Rps1-k. Four classes of cDNA of the sequence were isolated from etiolated hypocotyl tissues that express the Rps1-k-encoded Phytophthora resistance. Sequence analyses of a cDNA clone showed that the sequence is a member of the coiled coil-nucleotide binding site-leucine rich repeat (CC-NBS-LRR)-type of disease resistance genes. It showed 36% identity to the recently cloned soybean resistance gene Rpg1-b, which confers resistance against Pseudomonas syringae pv. glycinea, and 56% and 38% sequence identity to putative resistance gene sequences from lotus and Medicago truncatula, respectively. The soybean genome contains about 38 copies of the sequence. Most of these copies are clustered in approximately 600 kb of contiguous DNA of the Rps1-k region. We have identified a recombinant that carries both rps1-k- and Rps1-k-haplotype-specific allelomorphs of two Rps1-k-linked molecular markers. An unequal crossover event presumably led to duplication of alleles for these two physically linked molecular markers. We hypothesize that the unequal crossing over was one of the mechanisms involved in tandem duplication of CC-NBS-LRR sequences in the Rps1-k region.

[Report on the 89th Scientific Assembly and Annual Meeting of the Radiological Society of North America--micro-focus x-ray CT imaging of breast specimens with microcalcifications]

LEARNING OBJECTIVES

(1)Understand images of breast specimens with microcalcifications obtained by use of micro-focus CT. (2)Learn the relationship between mammographic features, pathologic characteristics, and micro-focus CT images. (3)Learn the usefulness of three-dimensional images in understanding of detailed structures and patterns of microcalcifications without cutting the specimen.

ABSTRACT

Microcalcifications are one of the important sign for early detection of breast cancer by use of mammography, and has resulted in the detection of nonpalpable cancer. However, it is difficult to distinguish between benign and malignant microcalcifications, thus causing high false-positive rate. Micro-focus CT employs a x-ray tube of a focal spot size less than 10 microns, and has high spatial resolution, thus resulting in more accurate visualization of structures of microcalcifications. We investigated the relationship between micro-focus CT images of breast specimens with microcalcifications, mammographic features and pathologic characteristics. Micro-focus CT imaging was comparable to pathologic images in terms of resolution and contrast. Microcalcifications were more clearly detected in micro-focus CT imaging than specimen radiographs. Three-dimensional imaging on microcalcifications provided a tool for studying the shape and distribution of calcifications. Micro-focus CT for breast imaging was very useful for understanding of structures and patterns of microcalcifications without cutting the specimen.

Fatigue characteristics of bioactive glass-ceramic-coated Ti–29Nb–13Ta–4.6Zr for biomedical application

A new surface-coating method by which CaP invert glass is used to improve the bioactivity of titanium alloys has been developed recently. In this method, the powder of CaP invert glass (CaO-P2O5-TiO2-Na2O) is coated on the surface of titanium alloy samples and heated between 1073 and 1123 K. With this treatment, a calcium phosphate layer mainly containing beta-Ca3(PO4)2 phase can be coated easily on titanium alloy samples. In the present study, the effect of this coating process on the fatigue properties of Ti-29Nb-13Ta-4.6Zr, a new metastable beta alloy for biomedical applications, has been investigated. The fatigue endurance limit of the coated alloy was found to be about 15% higher than that of uncoated alloy, as a result of the formation of a hard (alpha + beta) layer and a small amount of the omega phase during the coating process. The coating exhibits excellent adhesion to the substrate during the tensile and fatigue tests. Subsequent ageing at 673 K for 259.2 ks greatly improves the fatigue resistance of the coated alloy due to isothermal omega phase precipitation, and does not have obvious detrimental effect on the coating properties.

Characteristics of acoustic noise in echo-planar imaging

Characteristics of the acoustic noise generated by magnetic resonance imagers of different systems and performance levels were studied when operating in echo-planar imaging (EPI) sequence. Continuous equivalent A-weighted sound pressure levels (Leq) and peak impulse sound pressure levels (Lpeak) during EPI were measured in 12 clinical super-conducting MRI systems (0.5-1.5 T). Sound pressure levels and frequency spectra of EPI were compared with those of nine different pulse sequences. EPI sound pressure levels differed among institutions (Leq = 94.2 +/- 2.7 dBA. Lpeak = 109.1 +/- 3.5 dB), but these were within permissible noise exposure levels. Sound pressure levels during EPI were not significantly different from those during other pulse sequences. However, compared to other pulse sequences. EPI had a significantly greater proportion of acoustic noise in the high octave-frequency band. Single-shot EPI had relatively higher frequency noise and greater Leq than multishot EPI, but the difference in Leq decreased when the number of slices in multishot EPI was increased.

Effect of glutamate analogues on red-green opponent interaction in monkey electroretinograms

The effect of glutamate analogues on red-green opponent interaction was electrophysiologically investigated in anesthetized cynomolgus monkeys (Macaca fascicularis). Two approaches were employed: amplitude measurement and principal component analysis. Electroretinograms were recorded for 23 monochromatic stimuli (400-700 nm) at an equal energy with white light adaptation before and after treatment with the glutamate analogues, 2-amino-4-phosphonobutyric acid, cis -2,3-piperidine-dicarboxylic acid, or both. Before treatment, although spectral amplitude curves of the a- and d-waves showed single, broad peaks at about 550 nm, the b-wave curve had three peaks at about 460, 540 and 600 nm, indicating the occurrence of the red-green opponent interaction. Principal component analysis performed on these waveforms extracted three components with short, middle, and long wavelength peaks, well defined characteristics of the red-green opponency. After vitreal injection of 2-amino-4-phosphonobutyric acid, the a- and d-wave amplitudes were enhanced while the b-wave amplitude was almost completely diminished. However, principal component analysis showed basically similar characteristics to those before drug, suggesting that the red-green opponency was not affected. In contrast, after application of cis -2,3-piperidine-dicarboxylic acid, the a- and d-waves were diminished and the b-wave was enhanced as expected, however the enhancement was observed only in the short and middle wavelengths. As a result of this partial enhancement, the b-wave spectral amplitude curve showed only a single peak, unlike in the control. In addition, principal component analysis revealed a quite different result from the control; only two components with short and middle wavelength peaks and the component with long wavelength peak disappeared. Similar two components were also separated after the conjunction of both drugs. These results demonstrate that red-green opponency is greatly inhibited by cis -2,3 piperidine-dicarboxylic acid, and thus suggest that horizontal cells are related to a generation of the red-green opponency through a cone type selective or nonselective negative feedback.

Molecular typing of pathogenic fungi

In this Round Table, the application of several methods of molecular typing were discussed in reference to four important pathogenic fungi: Coccidioides immitis, Histoplasma capsulatum, Candida albicans and Paracoccidioides brasiliensis. Among the different methods the following were discussed: restriction fragment length polymorphisms (RFLP), single nucleotide polymorphisms, random amplified polymorphic DNA (RAPD), polymerase chain reaction (PCR)-RFLP and microsatellites. By means of these methods, several important biological questions related to speciation, mode of reproduction and population genetics could be approached. The basic information obtained from this approach has implications in the understanding of these pathogenic fungi in relation to their behavior and the development of pathogenic features, such as resistance to antimicrobials and virulence factors used for colonization of mammalian hosts. The knowledge obtained from these studies could also be used for the development of innovative diagnostic methods, as well as for novel therapeutic approaches and production of vaccines.

Calcium phosphate invert glass-ceramic coatings joined by self-development of compositionally gradient layers on a titanium alloy

A glass-ceramic layer containing beta-Ca3(PO4)2 crystals could be joined easily with a new type of titanium alloy (Ti-29Nb-13Ta-4.6Zr) consisting of a beta-titanium phase by heating the metal, on which glass powders with a composition of 60CaO x 30P2O5 7Na2O x 3TiO2 were placed, at 800 degrees C in air. Measurement of tensile bonding strength revealed that the joining between the coating layer and the substrate is very strong. Even after the large deformation (e.g., approximately 90 degrees in bending angle) of the titanium alloy, the coating layer was not peeled off from the substrate. A compositionally gradient layer in the TiO2-P2O5-Na2O-CaO system is developed automatically on the titanium alloy during the heating, resulting in the formation of the strong joining. By soaking in simulated body fluid at 37 degrees C, hydroxyapatite phase was formed newly on the surface of the coating layer.

Preparation and mechanical properties of polylactic acid composites containing hydroxyapatite fibers

Ceramic-polymer composite biomaterials were prepared by hot-pressing a mixture consisting of poly-L-lactic acid (PLA) and hydroxyapatite fibers (HAF) with dimensions of 40-150 microm length and 2-10 microm diameter, which were converted from beta-Ca(PO3)2 fibers. After PLA dissolved with methylene chloride was mixed with the fibers, the mixture was dried completely and subsequently hot-pressed uniaxially under a pressure of 40 MPa at 180 degrees C, resulting in the fabrication of the PLA/HAF composite. The modulus of elasticity was improved effectively even by introducing a small amount of HAF; almost no degradation in the bending strength was observed and the modulus of elasticity showed high values of 5-10 GPa when the fibers of 20-60 wt% were introduced. With increasing HAF content, the maximum strain decreases and the specimen is apt to show a brittle fracture; this result implies that HAF in the composites can share the applied load efficiently due to the formation of a bond between HAF and PLA.

Phylogenetic species recognition and species concepts in fungi

The operational species concept, i.e., the one used to recognize species, is contrasted to the theoretical species concept. A phylogenetic approach to recognize fungal species based on concordance of multiple gene genealogies is compared to those based on morphology and reproductive behavior. Examples where Phylogenetic Species Recognition has been applied to fungi are reviewed and concerns regarding Phylogenetic Species Recognition are discussed.

An index for human lens transparency related to age and lens layer: comparison between normal volunteers and diabetic patients with still clear lenses

OBJECTIVE

The light scattering intensity of normal, clear lenses varies with age and with the localization within the lens. Realizing the biometry of single lens areas together with their relevant light scattering intensity one should be able to calculate an index to express the lens transparency properties of normal human lenses in dependence on age. Performing the same procedure in cases of diabetic patients with still clear lenses it should become possible to obtain an index for the lens transparency properties of lenses under the 'risk factor' diabetes.

METHODS

748 eyes with transparent lenses in 383 healthy individuals and 134 eyes with clear lenses in 70 subjects with diabetes were examined. Scheimpflug slit images of the lens were documented by a Nidek EAS-1000 instrument. Biometry for measuring the distance of the single lens layers from the anterior capsule and densitometry for determining the light scattering intensity of six defined lens layers along the (theoretical) optical axis were performed. The index of the lens transparency properties was calculated using the light scattering intensity of a defined lens layer and its distance from the anterior capsule.

RESULTS

Lens thickness and light scattering intensities increased linearly with increasing age in the normal population as well as in the diabetic patients. The densitogram pattern of the light scattering intensities in the defined representative six points was similar in both populations, but in the diabetic group the lens thickness was larger and the light scattering intensities were higher at all ages.

CONCLUSION

The index of lens transparency properties calculated with the light scattering intensities of a certain lens area and its distance from the anterior capsule is a useful measure of lens clarity in dependence on age. 'Clear' lenses of the diabetic population show significantly higher indices for the lens transparency properties in all age groups.

Surface modification of calcium metaphosphate fibers

beta-calcium metaphosphate fibers having high aspect ratios of 10-120 with diameters of 2-10 microm show high strength and good biocompatibility. When the fibers are soaked in simulated body fluid at 37 degrees C, however, no calcium phosphate phase is newly formed on the fibers. In the present work, by treating the fibers at 70 degrees C with dilute NaOH aqueous solution, the surface phase was converted successfully into the orthophosphate phase that was in fine sizes and was adhered. After soaking the treated fibers in simulated body fluid at 37 degrees C for 30 days, a new calcium phosphate phase was precipitated. This was attributed to the surface phase modified using dilute NaOH. The treated fibers are expected to show bone-bonding ability, i.e. bioactivity.

Attentional processing of emotional information in obsessive-compulsive disorder

In order to investigate attentional processing of emotional information in obsessive-compulsive disorder (OCD), 14 patients with OCD and 28 normal control (NC) subjects were asked to name the background colors of anxiety-relevant, compulsion-relevant, positive and neutral words (an emotional Stroop color-naming test). The stimulus words were presented subliminally, and supraliminally. The time of subliminal presentation for each subject was determined in advance by the lexical decision task. In the subliminal condition, the delay for anxiety- and compulsion-relevant words, when compared with neutral words, was greater in OCD patients, while no difference was found in NC subjects. In the supraliminal condition, no delay was found for both OCD patients and NC subjects. In other words, OCD patients were more sensitive to threat information when it could not be identified with consciousness. Moreover, the present study compared checking OCD with cleaning OCD in the attentional processing of emotional information. As a result, it was found that checking OCD patients responded more slowly in naming the background color of subliminal emotional words than cleaning OCD patients. The results indicate that OCD patients, especially with checking compulsion, may have a deficit in automatic processing of threat information.

Bioactive ceramics prepared by sintering and crystallization of calcium phosphate invert glasses

Novel glass-ceramics were synthesized via sintering and crystallization by heating powder compacts of SiO2-free calcium phosphate invert glasses of 60CaO x 30P2O5 x 7Na2O x 3TiO2 or 60CaO x 30P2O5 x 7Na2O x 3MgO at 800-850 degrees C in air. The glass-ceramics were relatively dense materials consisting of crystalline phases such as beta-Ca3(PO4)2 and beta-Ca2P2O7 with glassy phases. The compacts were densified by the viscous flow of the glassy phases while heating. By soaking in simulated body fluid at 37 degrees C, a calcium phosphate phase was formed newly on the surface of the glass-ceramic derived from 60CaO x 30P2O5 x 7Na2O x 3TiO2 glass, while the phase was not formed on that derived from 60CaO x 30P2O5 x 7Na2O x 3MgO glass: the former was implied to show bioactivity. Composition of the glassy phase as the matrix varies with the additives such as TiO2 and MgO, and the chemical properties of the phase influence the bioactivity of the glass-ceramics. The glass-ceramic derived from 60CaO x 30P2O5 x 7Na2O x 3TiO2 glass has relatively high fracture toughness of K(IC) approximately 2 MPa m(0.5) and bending strength of 100-120 MPa.

[Epidemiological survey of ocular diseases in K Island, Amami Islands: prevalence of cataract and pterygium]

PURPOSE

An epidemiological survey of ocular disease was performed in a town of the Amami Islands in southwestern Japan.

OBJECT AND METHODS

A total of 339 participants over 40 years joined the survey. Among the 339 participants, the lens findings of 602 eyes of 301 subjects were analyzed.

RESULTS

The prevalence of lens opacification was 32.0, 54.0, 83.1, 96.9% and 100% among subjects in their 40, 50, 60, 70 s, and over 80 years. Lens opacification over grade II was 4.0, 12.7, 26.2, 60.0% and 83.3%. The cataract type most frequently seen was cortical (96.1%), followed by 48.5% with nuclear opacity and 14.7% with subcapsular type. A high prevalence was seen of pterygium at 25.4%. Although the prevalence of lens opacification was higher in the group with pterygium in their 70 s, no significant difference was noticed in persons in their 40, 50, 60 s, and over 80 years old between the pterygium and non-pterygium groups.

CONCLUSIONS

Similarly to the results of a previous survey in Okinawa, Noto, and Hokkaido, the main type of lens opacification was cortical in Amami. The prevalence of nuclear opacification and pterygium was higher than in Noto and Hokkaido, and close to that seen in Okinawa.

Phylogenetic relationships of varieties and geographical groups of the human pathogenic fungus Histoplasma capsulatum Darling

The phylogeny of 46 geographically diverse Histoplasma capsulatum isolates representing the three varieties capsulatum, duboisii, and farciminosum was evaluated using partial DNA sequences of four protein coding genes. Parsimony and distance analysis of the separate genes were generally congruent and analysis of the combined data identified six clades: (i) class 1 North American H. capsulatum var. capsulatum, (ii) class 2 North American H. capsulatum var. capsulatum, (iii) Central American H. capsulatum var. capsulatum, (iv) South American H. capsulatum var. capsulatum group A, (v) South American H. capsulatum var. capsulatum group B, and (vi) H. capsulatum var. duboisii. Although the clades were generally well supported, the relationships among them were not resolved and the nearest outgroups (Blastomyces and Paracoccidioides) were too distant to unequivocally root the H. capsulatum tree. H. capsulatum var. farciminosum was found within the South American H. capsulatum var. capsulatum group A clade. With the exception of the South American H. capsulatum var. capsulatum group A clade, genetic distances within clades were an order of magnitude lower than those between clades, and each clade was supported by a number of shared derived nucleotide substitutions, leading to the conclusion that each clade was genetically isolated from the others. Under a phylogenetic species concept based on possession of multiple shared derived characters, as well as concordance of four gene genealogies, H. capsulatum could be considered to harbor six species instead of three varieties.