Variability of parvovirus B19 genotype 2 in plasma products with different compositions in the inactivation sensitivity by liquid-heating.

BACKGROUND AND OBJECTIVES: Our previous report showed that parvovirus B19 genotype 1 in different solutions derived from plasma preparations showed different heat-sensitivity patterns during liquid-heating. In this study, we similarly examined B19 genotype 2. MATERIALS AND METHODS: Two plasma samples one containing B19 genotype 1 and the other genotype 2 DNA were used. Four process samples collected immediately before the heat treatment step in the manufacture of albumin, immunoglobulin, haptoglobin and antithrombin preparations were spiked with B19 and subsequently treated at 60°C for 10 h. A low pH immunoglobulin solution was also spiked with B19 and treated at room temperature for 14 days. Infectivity was then measured. RESULTS: B19 genotype 2, similar to genotype 1, showed three patterns of inactivation: (i) a rapid inactivation in the albumin and immunoglobulin preparations, (ii) a slow inactivation in the haptoglobin preparation and (iii) only limited inactivation in the antithrombin preparation. Its sensitivity in the low pH immunoglobulin solutions also resembled that of genotype 1. CONCLUSION: Both genotypes 1 and 2 of B19 varied in sensitivity to liquid-heating and low pH among different plasma preparations.

Reliability and validity of Japanese version of the McGill Quality of Life Questionnaire assessed by application in palliative care wards.

The McGill Quality of Life Questionnaire (MQOL), which consists of 16 items constructing physical, psychological, existential and support subscales and one item of overall quality of life (QOL), has been developed to assess QOL of terminal cancer patients. To examine if MQOL Japanese version (MQOL-J) is applicable, it was administered to 83 terminal cancer patients in palliative care wards several days after admission and then 7 to 10 days after the first interview. Cronbach's alpha coefficient for four subscales was 0.584-0.860. Sixteen items were classified into four factors by factor analysis, similar to the original English version. The results indicated that psychological and existential domains of the MQOL-J significantly related to overall QOL. Existential and support domains as well as overall QOL were significantly improved between the first and second interviews, although performance status assessed by Eastern Cooperative Oncology Group worsened. It is suggested that MQOL-J can reflect perceived health status of terminal cancer patients.

Electronic structure and magnetic anisotropy of a constrained Fe chain in an electric field.

The electronic structure and magnetic anisotropy were studied for a constrained iron chain in an electric field by means of the first-principles approach. The electron induced by the electric field was found to occupy mainly the extended s-like orbitals which is well hybridized with the d(3z(2)-r(2)) localized orbital. The magnetic anisotropy was observed to decrease with the number of induced electrons and to depend on the magnetization direction. The magnetization perpendicular both to the chain and the electric field modifies the electron dispersion relation to be asymmetrical, which implies an expectation of variable transport property with both the external electric and magnetic fields.

Extent of hepatitis E virus elimination is affected by stabilizers present in plasma products and pore size of nanofilters.

BACKGROUND AND OBJECTIVE: To investigate the physico-chemical properties of hepatitis E virus (HEV) with regard to inactivation/removal, we have studied four isolates with respect to sensitivity to heat during liquid/dry-heating as well as removal by nanofiltration. MATERIALS AND METHODS: Hepatitis E virus in an albumin solution or phosphate-buffered saline (PBS) was liquid-heated at 60 degrees C for a preset time. HEV in a freeze-dried fibrinogen containing stabilizers was also dry-heated at 60 or 80 degrees C for a preset time. In addition, to clarify the removal of HEV, the purified virus in PBS was filtered using several types of virus-removal filter (nanofilters) that have different pore sizes. HEV infectivity or genome equivalents before and after the treatments were assayed by a semiquantitative cell-based infectivity assay or quantitative polymerase chain reaction assay, respectively. RESULTS: Hepatitis E virus isolates in albumin solutions were inactivated slowly at 60 degrees C for 5 h and the resultant log reduction factor (LRF) was from 1.0 to > or = 2.2, whereas the virus in PBS was inactivated quickly to below the detection limit and the LRF was > or = 2.4 to > or = 3.7. The virus in a freeze dried fibrinogen containing trisodium citrate dihydrate and l-arginine hydrochloride as stabilizers was inactivated slowly and the LRF was 2.0 and 3.0, respectively, of the 72 h at 60 degrees C, but inactivated to below the detection limit within 24 h at 80 degrees C with an LRF of > or = 4.0. The virus in PBS was also confirmed as to be approximately 35 nm in diameter by nanofiltration. These results are useful for evaluating viral safety against HEV contamination in blood products. CONCLUSION: The sensitivity of HEV to heat was shown to vary greatly depending on the heating conditions. On the other hand, the HEV particles were completely removed using 20-nm nanofilters. However, each inactivation/removal step should be carefully evaluated with respect to the HEV inactivation/removal capacity, which may be influenced by processing conditions such as the stabilizers used for blood products.

Abnormal fundus autofluorescence patterns in myopic choroidal neovascularisation.

BACKGROUND/AIMS: To investigate fundus autofluorescence (FAF) findings in eyes with myopic choroidal neovascularisation (CNV). METHODS: Observational case series. Twenty-seven consecutive eyes with CNV for at least 1 year were included. FAF patterns, time after the onset of CNV seen on FAF and FAF changes were evaluated. RESULTS: The following patterns were observed: pattern I (n = 2), relative hypoautofluorescence around the CNV surrounded by hyperautofluorescence a mean of 17 months after CNV onset; pattern II (n = 11), small lobular or multilobular well-defined FAF defects within a relatively hypoautofluorescent region surrounded by hyperautofluorescence a mean of 35 months after onset; pattern III (n = 4), large lobular or multilobular well-defined FAF defects surrounded by hyperautofluorescence a mean of 59 months after onset; and pattern IV (n = 10), large lobular or crescent-shaped well-defined FAF defects a mean of 107 months after onset. Well-defined FAF defects corresponded to chorioretinal atrophy on colour fundus photographs. During the follow-up period, two eyes with pattern I evolved into pattern II. Lobular or multilobular well-defined FAF defects enlarged in 11 eyes (pattern II, nine eyes; pattern III, two eyes). CONCLUSION: Autofluorescent changes progress over time through pattern grading. A pattern classification might be helpful to predict chorioretinal atrophy changes around myopic CNV.

Marked vascular changes of polypoidal choroidal vasculopathy after photodynamic therapy.

AIMS: To clarify vascular changes of polypoidal choroidal vasculopathy (PCV) after photodynamic therapy (PDT). METHODS: Thirty-one eyes underwent PDT with verteporfin and were followed every 3 months with indocyanine green angiography (ICGA) using confocal scanning ophthalmoscope and optical coherence tomography (OCT) for over 15 months and the findings recorded. RESULTS: The mean follow-up period was 19.2 months. Regression of the polypoidal lesions were confirmed once in 29 eyes (94%) on ICGA and OCT. Some lesions recurred at the initial regions (n = 5 eyes), at different regions connected to the branching vascular network (n = 4 eyes), and at both regions (n = 1 eye) (mean 11.4 (SD 1.9) months) after initial PDT. The branching vascular network remained in all eyes and enlarged in 13 eyes (42%) at the final visit. The vascular features of residual branching vascular networks changed (n = 7 eyes); fibrinous subretinal exudation developed (n = 4 eyes), and the retinal pigment epithelium was elevated similar to vascularised pigment epithelial detachment (n = 3 eyes). CONCLUSION: Polypoidal lesions of PCV are treatable with PDT; however, they often recur. The branching vascular networks do not regress and allow the recurrence of polypoidal lesions at the network termini. Alterations of the vascular features may occur; careful observation is needed after PDT.

Efficacy of intravitreal bevacizumab for polypoidal choroidal vasculopathy.

AIMS: The aim of the study was to assess the short-term efficacy of intravitreal injections of bevacizumab for polypoidal choroidal vasculopathy (PCV). METHODS: Intravitreal bevacizumab (1 mg) was injected into 11 eyes of 11 patients with PCV in this retrospective, interventional case series. The main outcome measure was the change in the polypoidal vessels on indocyanine green angiography (IA) 3 months after injection. The foveal height determined by optical coherence tomography and the best-corrected visual acuity (BCVA) also were evaluated before and after treatment. RESULTS: At baseline, subretinal fluid was observed in five eyes and a pigment epithelial detachment in eight eyes. The foveal height 1 month after injection decreased significantly (p = 0.023), but at 3 months, no significant decrease was observed, although an additional injection was administrated in five of 11 eyes. The IA at 3 months showed resolution of polyps in one eye but residual or enlarged lesions in the other ten eyes. The BCVA did not improve significantly, although the subjects had relatively good BCVA at baseline (mean 0.45). CONCLUSION: Intravitreal injection of bevacizumab may reduce the fluid from PCV but seems to be ineffective for diminishing its choroidal vascular changes.

Variability of parvovirus B19 to inactivation by liquid heating in plasma products.

BACKGROUND AND OBJECTIVES: Previously, we reported that although human parvovirus B19 in albumin and intravenous immunoglobulin preparations was rapidly inactivated during liquid heating, in contrast to other parvoviruses such as canine parvovirus, sensitivity to heat was highly dependent on the composition of the solution. In this study, we aimed to further elucidate the sensitivity to heat of B19 in haptoglobin and antithrombin (previously named antithrombin III) preparations during liquid heating. MATERIALS AND METHODS: Two different solutions collected immediately before heat treatment of haptoglobin and antithrombin preparations were spiked with B19 and subsequently treated at 60 degrees C for 10 h. B19 DNA-positive, anti-B19 IgG/IgM-negative plasma was used as a source of B19. The residual infectivity in each sample was measured using a B19 cell-based infectivity assay with an mRNA polymerase chain reaction. RESULTS: B19 in different plasma preparations showed different heat-sensitivity patterns during liquid heating: (i) slow inactivation in haptoglobin preparations, and (ii) only limited inactivation in antithrombin preparations. The kinetics of inactivation was greatly different from that in our previous studies in which the virus was shown to be rapidly inactivated in albumin and intravenous immunoglobulin preparations. CONCLUSION: B19 has unique properties in terms of heat sensitivity, depending on the composition of the solution during liquid heating. This finding may indicate the need for caution when interpreting the sensitivity of B19 to heat.

Intravitreal injection of bevacizumab for choroidal neovascularisation associated with pathological myopia.

AIM: To assess the efficacy and safety of an intravitreal injection of bevacizumab (Avastin(R)) for myopic choroidal neovascularisation (mCNV). METHODS: Intravitreal bevacizumab (1 mg) was injected into eight eyes of eight patients with mCNV in this non-randomised, interventional case series. The best-corrected visual acuity (BCVA) was measured and the optical coherence tomography (OCT) and fluorescein angiography findings were examined before and after treatment. The minimum follow-up time was 3 months. RESULTS: The mean BCVA was 0.26 before treatment and 0.51 at the last visit (p = 0.009). The BCVA improved to two or more lines in six eyes (75%) and remained the same in two eyes (25%). Leakage from the mCNV on fluorescein angiography decreased in seven eyes (87.5%). The choroidal neovascularisation area on fluorescein angiography (p = 0.049) and the foveal thickness on OCT images decreased significantly (p = 0.027) after the treatment. No major complications developed. CONCLUSION: Intravitreal injection of bevacizumab seems to be an effective and safe treatment for mCNV.

Magnetic anisotropies of iron on the Pt(111) surface.

We have studied magnetic anisotropies of Fe atoms on the platinum (111) surface, employing a fully relativistic pseudopotential and plane wave method with the local spin density approximation. We investigated three surface structures with different Fe monolayer coverages: full coverage, half-coverage and quarter-coverage. The effect of surface relaxation has been included. It was found that the magnetic easy axis of the system is within the surface plane for all systems investigated. In the system of an Fe chain on Pt(111), having an anisotropic local structure, the magnetic anisotropy energy is much enhanced after surface relaxation. This absolute value is larger compared with the value for bulk alloy and the magnetic easy axis is directed parallel to the alignment of Fe atoms.

Heat sensitivity of human parvovirus B19.

BACKGROUND AND OBJECTIVES: To date there has been no published report on a systematic evaluation of the heat sensitivity of human parvovirus B19 (B19) and the related safety of the plasma-derived fractionated products. In this study, we examined the heat sensitivity of B19 by using the infectivity assay with cultured cells. MATERIALS AND METHODS: The heat sensitivity of B19 was examined by measuring the reduction in viral infectivity titres after heating liquid containing B19 at 60 degrees C. Viral infectivity was assayed by detection of viral antigens or viral mRNA in infected cells. As a control, canine parvovirus (CPV) was also heat-treated. RESULTS: B19 displayed quite different inactivation kinetics to CPV when both were heated in liquid at 60 degrees C. In sharp contrast to the latter, B19 was rapidly inactivated within 1 h when the virus was suspended in 5% or 25% human serum albumin solution, phosphate-buffered saline, or complete medium. However, B19 appeared to be resistant to heat inactivation in liquid containing 60% sucrose. CONCLUSIONS: The heat sensitivity of B19 in liquid was clearly different from that of CPV. Significantly, the efficiency to inactivate B19 and reduce its infectivity following heating in liquid was mainly affected by the composition of the solutions used for virus suspension.

Disinfection kinetics of Legionella pneumophila by ultraviolet irradiation.

Disinfection kinetics of Legionella pneumophila by ultraviolet irradiation was investigated. The change in viable cell concentration with exposure time could be divided into three steps: lag step in which little change in viable cell concentration was observed, fast disinfection step and slow disinfection step. The slow disinfection step was not observed at the initial cell concentrations below about 10(6) cfu/mL. The disinfection kinetics were well described with two parameters; lag time and disinfection rate constant of the fast disinfection step. The effects of UV intensity, temperature and initial cell concentration in the kinetic parameters were investigated. With increasing initial cell concentration, the lag time decreased and the disinfection rate constant increased. The effects of initial cell concentration on the kinetic parameters were considered to be attributed to the decrease in the effective UV irradiation intensity due to the partial shield of UV light by the disinfected cells. The empirical correlations were presented for predicting the lag time and disinfection rate constant. Furthermore, UV disinfection of L. pneuophila in a model hot-tub connected with external irradiation chamber was also discussed.

Two patterns of opacity in corneal dystrophy caused by the homozygous BIG-H3 R124H mutation.

PURPOSE: To investigate the opacity pattern in corneas with an Arg124His (R124H) homozygous mutation of the BIG-H3 gene. METHODS: Slit-lamp examination was performed on eight patients with corneal dystrophy resulting from a genetically confirmed BIG-H3 R124H homozygous mutation. The birthplace of each patient also was determined. RESULTS: Slit-lamp examination disclosed two types of opacity patterns in corneas with the BIG-H3 R124H homozygous mutation. Type I (n = 4) is a spot-like opacity present in the anterior stroma in which the lesions are confluent. Type I is the same pattern that previous reports have shown to be caused by the BIG-H3 R124H homozygous mutation. The type II corneal opacity pattern (n = 4) is a reticular opacity in the anterior stroma with round translucent spaces. Type II opacity has not been reported previously in association with any corneal dystrophy. The patients with the type I opacity do not share a common birthplace; however, interestingly, the patients with the type II opacity traced their origin to Tottori prefecture in western Japan. CONCLUSION: The BIG-H3 homozygous R124H mutation induces the development of two distinct patterns of corneal opacity, the recognition of which can establish an accurate diagnosis of corneal dystrophy caused by the homozygous BIG-H3 R124H mutation independent of genetic analysis. In addition, genetic factors or circumstantial influences other than the gene responsible for the corneal dystrophy may influence the pattern of corneal opacity.

The effect of TGF-beta1 on differential gene expression profiles in human corneal epithelium studied by cDNA expression array.

PURPOSE: TGF-betas regulate cell proliferation and differentiation, and they play important roles in maintenance of corneal epithelium. However, the precise function of TGF-betas in the corneal epithelium remains unclear. In this study, cDNA expression array technology was used to demonstrate the effect of TGF-beta1 on the simultaneous expression of a large number of genes in cultured human corneal epithelial cells (HCECs). The change in protein level expression of the specific genes influenced by TGF-beta1 was also investigated. METHODS: Human cDNA expression array technology was used to study the simultaneous expression of 1176 specific cellular genes in HCECs incubated with TGF-beta1 (10 ng/ml). Moreover, gene-specific semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) was used to confirm the gene expression pattern measured by the cDNA expression array. Western blot analysis was used to examine protein expression of the specific genes in the presence or absence of TGF-beta1. RESULTS: TGF-beta1 significantly upregulated the expression of 19 genes and significantly downregulated ras-related protein, caspase10, and beta4-integrin in the treated HCECs. The expression of 277 genes including alpha3-integrin, PAI-2, transferrin receptor, and cyclin-D1 was studied. Semiquantitative RT-PCR analysis confirmed the TGF-beta1-mediated changes in expression patterns of these genes. Furthermore, Western blot analysis revealed that TGF-beta1 remarkably decreased PAI-2, transferrin receptor, and integrin alpha3, and increased caspase10 on the protein level. CONCLUSIONS: TGF-beta1 regulates the expression of specific types of genes in HCECs. These results strongly suggest that TGF-beta1 is critically involved in the maintenance of the corneal epithelium through the control of a network of various signal-transduction pathways.

Rapid detection of M1S1 mutations by the protein truncation test.

PURPOSE: To determine a method of rapid detection of M1S1 gene mutations in patients with gelatinous droplike corneal dystrophy. METHODS: Forty-one patients from 35 families with gelatinous drop-like corneal dystrophy were studied. The entire coding region of the M1S1 gene was screened using the protein truncation test (PYT), with a polymerase chain reaction fragment amplified from genomic DNA serving as a template of in vitro translation. RESULTS: Homozygous or compound heterozygous mutations were detected in all patients by a single reaction of the PTT. This result matched those obtained using the polymerase chain reaction-restriction fragment length polymorphism and direct sequence analyses. The Q118X mutation was present in 63 of the 70 alleles, accounting for 90% of the disease-associated chromosomes in Japanese patients. CONCLUSIONS: The PTT is useful for detecting mutations in the M1S1 gene. This technique showed that the Q118X mutation is a founder mutation in Japanese patients with gelatinous droplike corneal dystrophy, and it reflects the linkage disequilibrium reported previously.

The spectrum of beta ig-h3 gene mutations in Japanese patients with corneal dystrophy.

PURPOSE: This study was undertaken to identify beta ig-h3 gene mutations in Japanese patients with granular corneal dystrophy (GCD), Avellino corneal dystrophy (ACD), lattice corneal dystrophy (LCD), and Reis-Bücklers' corneal dystrophy (RBCD). R124H, R124C, R555W, and R555Q mutations have been reported in Europe to cause ACD, LCD type I, GCD, and RBCD, respectively. METHODS: In total, 91 Japanese patients who had been clinically diagnosed with GCD, LCD, or RBCD were investigated to determine whether they had mutations in the beta ig-h3 gene. Genomic DNA was amplified using the polymerase chain reaction and analyzed using single-strand conformation polymorphism techniques. Mutations were identified using the direct sequencing method. RESULTS: In 68 unrelated patients who had been diagnosed with GCD, 62 patients (91%) were found to have the R124H mutation, which has been reported to cause ACD, whereas only six patients (9%) had the R555W mutation. In LCD patients, 10 patients with type I disease had the R124C mutation, and 10 patients with type IIIA disease had a P501T mutation. One patient with atypical LCD had an L527R mutation. In two patients with RBCD, one had an R555Q mutation and the other patient with geographic opacities was found to have an R124L mutation. CONCLUSIONS: Depending on the specific mutation in the beta ig-h3 gene, the phenotypes of corneal dystrophy may differ. Our results indicate that assay of mutations in the beta ig-h3 gene is required to establish a correct diagnosis.

X-linked retinoschisis with point mutations in the XLRS1 gene.

BACKGROUND: X-linked retinoschisis (XLRS) is a relatively rare vitreoretinal dystrophy that causes visual loss in young men. Recently, a gene responsible for this disease, designated XLRS1, was identified, and several deleterious gene mutations were reported. OBJECTIVE: To analyze Japanese patients clinically diagnosed as having XLRS formutational changes in the XLRS1 gene. METHODS: Ten patients with XLRS underwent full ophthalmologic examination, including slitlamp biomicroscopy and dilated funduscopy. Genomic DNA was isolated from leukocytes, and all exons of the XLRS1 gene were amplified by polymerase chain reaction and analyzed using a direct sequencing method. RESULTS: Point mutations in the XLRS1 gene were identified in all 10 patients. The mutations were identical in each of 2 pairs of brothers. Six of the point mutations represented missense mutations, 1 was a nonsense mutation, and 1 was a frameshift mutation. Five of the mutations are newly reported herein. CONCLUSIONS: The discovery of new point mutations in this study increases the available information regarding the spectrum of genetic abnormalities and clinical manifestations of XLRS. However, the limited data failed to reveal a correlation between mutation and disease phenotype. CLINICAL RELEVANCE: Identification of mutations in the XLRS1 gene and expanded information on clinical manifestations will facilitate early diagnosis, appropriate early therapy, and genetic counseling regarding the prognosis of XLRS.

Oxidative DNA damage by minor metabolites of toluene may lead to carcinogenesis and reproductive dysfunction.

Recently, the concern that toluene might have carcinogenic and reproductive toxic potential has been raised. We investigated the ability of DNA damage by minor metabolites of toluene, methylhydroquinone, and methylbenzoquinone, using (32)P-5'-end-labeled DNA fragments obtained from the human genes. Methylhydroquinone caused Cu(II)-mediated DNA damage, whereas methylbenzoquinone did only in the presence of NADH. DNA damage by methylbenzoquinone was weaker than that by benzoquinone, a metabolite of carcinogenic benzene. Formation of 8-oxo-7, 8-dihydro-2'-deoxyguanosine by metabolites of toluene increased with its concentration in the presence of Cu(II) and NADH. Generation of O(*-)(2) and semiquinone radicals was detected by UV-visible and ESR spectroscopies, respectively. These results suggest that these metabolites may play some roles in expression of carcinogenicity and reproductive toxicity of toluene. We have discussed the differences of carcinogenic potency between toluene and benzene in relation to the amount of metabolites and their ability to damage DNA.