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Biomedical subjects

F Nakao

Publications and source records attributed to F Nakao.

At least 19 recordsLinked to original sources

Association studies of CTLA-4, CD28, and ICOS gene polymorphisms with type 1 diabetes in the Japanese population.

Co-stimulatory molecules of CD28, cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), and the newly identified inducible co-stimulator (ICOS) are expressed on cell surfaces and provide regulatory signals for T-cell activation. Their genes are candidate susceptibility genes for type 1 diabetes because they co-localize to Chromosome 2q33 with the IDDM12 locus. After determining the genomic structure and screening for polymorphisms of the ICOS gene, we performed association studies between newly identified polymorphisms of the ICOS gene, together with known polymorphisms of CD28 and CTLA-4 genes, and type 1 diabetes. The 49A/G dimorphism in exon 1 and the (AT)n in the 3' untranslated region of the CTLA-4 gene were significantly associated with type 1 diabetes. Evaluation of the CTLA-4 49A-3'(AT)n 86-bp haplotype frequency in patients and controls confirmed the results from the analysis of each polymorphic site. Dimorphism in intron 3 of the CD28 gene was associated with type 1 diabetes only in the early-onset group. In contrast, there was no association with the microsatellite polymorphisms in the ICOS gene or dimorphisms in the promotor region of CTLA-4. Of the three genes encoding co-stimulatory molecules, the CTLA-4 gene appears to confer risks for the development of type 1 diabetes.

Abatacept↗

Influence of cataract surgery on automated perimetry in patients with glaucoma.

PURPOSE: To investigate the influence of cataract surgery on automated perimetry in patients with glaucoma. DESIGN: Interventional case series. METHODS: A total of 105 eyes of 105 consecutive patients with glaucoma who were scheduled for cataract surgery underwent Humphrey static threshold testing (30-2 program) before and at 1 month after surgery. These eyes were divided into two groups based on the presence of absolute or near absolute (dense) scotomata before surgery (minimum threshold value 5 decibels or less). Changes in numbers of the dense scotomata, mean deviation, pattern standard deviation, and corrected pattern standard deviation were analyzed. RESULTS: No significant changes were found in the numbers of dense scotomata and central dense scotomata within five-degree visual fields between before and after surgery. In the group with dense scotomata, the mean pattern standard deviation and corrected pattern standard deviation worsened significantly after surgery, whereas the mean deviation improved significantly. However, in the group without dense scotomata, the pattern standard deviation and corrected pattern standard deviation showed a slight improvement, whereas the mean deviation improved significantly. When the central scotoma was present in two or fewer meridians before surgery, the mean visual acuity after surgery reached 20/25 and was better than that in patients with three or four central scotomata (P =.0014). CONCLUSIONS: Cataract does not produce a dense scotoma on automated perimetry. However, because it does produce relative scotomata, actual glaucomatous visual field defects may be hidden to some extent. When a central dense scotoma is present before surgery in two or fewer meridians, the patient may well achieve substantial improvement in postoperative visual acuity.

Adult↗

Correlation between pupillary size and intraocular lens decentration and visual acuity of a zonal-progressive multifocal lens and a monofocal lens.

OBJECTIVE: To see whether there is a correlation between pupillary area or intraocular lens (IOL) decentration and tilt and the visual acuity (VA) at all distances for eyes with a zonal-progressive multifocal IOL or a monofocal IOL. DESIGN: Comparative, nonrandomized, interventional study. PARTICIPANTS: Fifty-five eyes of 55 patients undergoing five-zone refractive multifocal IOL implantation and 55 eyes of 55 age-matched patients undergoing monofocal IOL implantation. INTERVENTION: All eyes underwent phacoemulsification and IOL implantation. MAIN OUTCOME MEASURES: The VAs from far to near distances were examined using an all-distance vision tester at 1 month after surgery. The pupillary area was also measured using an infrared pupillometer, and the degrees of IOL decentration and tilt were measured using a Scheimpflug videophotography system. Univariate associations between VA and the pupillary area and IOL decentration or tilt were evaluated statistically. RESULTS: The mean intermediate VAs and contrast sensitivities at all spatial frequencies in the multifocal IOL group were worse than those in the monofocal IOL group, whereas near VA was better in the multifocal group. In the multifocal group, smaller pupillary area was associated significantly with worse near logarithm of the minimum angle of resolution (LogMAR) VA (r = 0.636), but not with far or intermediate VAs. When pupil diameter was 4.5 mm or greater, near mean VA reached 20/63. A greater degree of IOL decentration was associated significantly with worse far and intermediate LogMAR VAs (r = 0.460 at 5.0 m and 0.527 at 1.0 m) but not with near VA. When decentration was 0.9 mm or greater, distance mean VA did not reach 20/32. However, the correlation between tilt and VA was not statistically significant. In the monofocal group, no significant correlation was found between pupillary area, IOL decentration, or tilt and the VA. CONCLUSIONS: Smaller pupil size is correlated significantly with worse near VA, whereas greater decentration is correlated with worse distance and intermediate VA in eyes with refractive multifocal IOLs. Specifically, a pupil diameter of less than 4.5 mm cannot provide useful near VA, and decentration of 0.9 mm is the maximum allowable limit for adequate distance VA. However, pupil size and IOL decentration do not influence VA in eyes with monofocal IOLs.

Adult↗

Changes in posterior capsule opacification after poly(methyl methacrylate), silicone, and acrylic intraocular lens implantation.

PURPOSE: To prospectively evaluate the progression of posterior capsule opacification (PCO) after poly(methyl methacrylate) (PMMA), silicone, and acrylic intraocular lens (IOL) implantation. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: Three hundred eyes of 300 patients scheduled to have IOL implantation were initially randomized into 3 groups based on IOL type: PMMA, silicone, or acrylic. Of the 300 eyes, 269 completed the follow-up. The PCO density in these eyes was measured 1 week and 3, 6, 12, 18, and 24 months postoperatively using special computer software developed for the Scheimpflug videophotography system. Visual acuity and the incidence of neodymium:YAG (Nd:YAG) laser capsulotomy were also examined. RESULTS: Three months postoperatively and later, the mean PCO value in the PMMA group increased significantly (P <.0001); the increase in the silicone and acrylic groups was not significant. The PCO value in the PMMA group was significantly greater than in the silicone or acrylic group (P <.0001). The PCO value in the acrylic group was slightly less than in the silicone group at 18 and 24 months, but the difference was marginal. The survival rate not requiring Nd:YAG capsulotomy was least in the PMMA group, followed by the silicone and acrylic groups in that order (P <.0001). The mean logMAR visual acuity in the PMMA group increased postoperatively and was worse than in the silicone or acrylic group. CONCLUSIONS: The degree of PCO after PMMA IOL implantation progressed significantly with time, while the progression after silicone and acrylic IOL implantation was slight. Therefore, PCO in eyes with a PMMA IOL was significantly more extensive than in those with a silicone or acrylic IOL and resulted in marked impairment of visual acuity.

Acrylic Resins↗

Effect of cataract surgery on intraocular pressure control in glaucoma patients.

PURPOSE: To examine the effect of cataract surgery on intraocular pressure (IOP) control in eyes with angle-closure glaucoma (ACG) and open-angle glaucoma (OAG). SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: This study included 74 eyes with ACG and 68 eyes with OAG having cataract surgery. The IOP was measured and the number of glaucoma medications recorded preoperatively, 1 month postoperatively, and then every 3 months. The IOP control in the 2 groups was compared using survival analysis, with failure criteria being an IOP greater than 21 mm Hg, addition of medications, or the need for additional glaucoma surgery. RESULTS: The mean IOP and number of medications decreased significantly after surgery in both groups (P <.0001). However, the mean decrease in IOP and percentage of IOP reduction in the ACG group were greater than in the OAG group, and fewer medications were required in the ACG group. The cumulative survival probability of IOP control at 24 months was 91.9% in the ACG group and 72.1% in the OAG group. The survival curve in the ACG group was significantly better than in the OAG group (P =.0012). The IOP was controlled without medication in 30 eyes (40.5%) in the ACG group and 13 (19.1%) in the OAG group; the difference between groups was significant (P =.0055). CONCLUSIONS: Cataract surgery substantially reduced IOP and the number of medications required for IOP control in glaucomatous eyes. Specifically, cataract extraction normalized the IOP in most eyes with ACG.

Aged↗

Association of IFN-gamma and IFN regulatory factor 1 polymorphisms with childhood atopic asthma.

BACKGROUND: IFN-gamma and related molecules play important roles in the differentiation and function of TH2 cells. OBJECTIVE: We sought to determine whether IFNG and related genes contribute to any susceptibility to atopic asthma, a representative TH2-dominant disorder. METHODS: We investigated the association of IFNG (CA repeat polymorphism within the first intron), IRF1 (GT repeat polymorphism within the intron 7), IFNGR1 (Val 14 Met), and IFNGR2 (Gln 64 Arg) gene polymorphisms with atopic asthma in the Japanese child population. RESULTS: A significant association (P =.0018) was observed between IFNG gene polymorphism and atopic asthma. The tendency was more prominent in patients with age of onset of 3 years or younger (P =.0004) or patients with a family history of allergic diseases (P =.0038). Furthermore, there was a significant association between IRF1 gene whole-allele distribution and atopic asthma (P =.044). The tendency was more prominent in patients with onset at 3 years of age or less (P =.0058). On the other hand, IFNGR1 and IFNGR2 gene polymorphisms showed no association with atopic asthma. CONCLUSION: These results suggested that among IFNG and related genes, IFNG and IRF1 genes confer genetic susceptibility to atopic asthma in Japanese children.

Adolescent↗

Anterior capsule contraction and intraocular lens decentration and tilt after hydrogel lens implantation.

AIM: To prospectively investigate changes in the area of the anterior capsule opening, and intraocular lens (IOL) decentration and tilt after implantation of a hydrogel IOL. METHODS: 100 patients underwent implantation of a hydrogel IOL in one eye and an acrylic IOL implantation in the opposite eye. The area of the anterior capsule opening, and the degree of IOL decentration and tilt were measured using the Scheimpflug videophotography system at 3 days, and at 1, 3, and 6 months postoperatively. RESULTS: The mean anterior capsule opening area decreased significantly in both groups. At 6 months postoperatively, the area in the hydrogel group was significantly smaller than that in the acrylic group. The mean percentage of the area reduction in the hydrogel group was also significantly greater than that in the acrylic group, being 16.9% in the hydrogel group and 8.8% in the acrylic group. In contrast, IOL decentration and tilt did not progress in either group. No significant differences were found in the degree of IOL decentration and tilt throughout the follow up period. CONCLUSIONS: Contraction of the anterior capsule opening was more extensive with the hydrogel IOL than with the acrylic IOL, but the degree of IOL decentration and tilt were similar for the two types of lenses studied.

Acrylic Resins↗

Effect of low-intensity warfarin therapy on left atrial thrombus resolution in patients with nonvalvular atrial fibrillation: a transesophageal echocardiographic study.

The presence of left atrial thrombus (LAT) is associated with an increased risk of embolic stroke. However, it has yet to be established definitively whether low-intensity warfarin therapy (INR: 1.5-2.0) can prevent LAT formation in patients with nonvalvular atrial fibrillation (NVAF). The present study analyzed the clinical and transesophageal echocardiography (TEE) features of 123 such patients to identify risk factors for LAT formation and the efficacy of prophylactic low-intensity warfarin therapy. Left atrial thrombi were found in 35 patients (28%) in whom systemic hypertension (49% vs 23%; p<0.01) and ischemic heart disease (17% vs 3%; p<0.01) were more frequent. Left ventricular ejection fraction (54+/-14% vs 60+/-11%; p<0.05), left ventricular end-diastolic dimension (51+/-7 mm vs 48+/-5 mm; p<0.05), spontaneous echo contrast (2.2+/-0.7 vs 1.4+/-0.9; p<0.01), left atrial diameter (50+/-6 mm vs 43+/-7 mm; p<0.01), left atrial appendage blood velocity (22.3+/-8.7 cm/s vs 37.2+/-21.5 cm/s; p<0.01) and the incidence of left ventricular hypertrophy (37% vs 15%; p<0.01) were also significantly different between the groups. Fourteen patients received continuous warfarin therapy (target INR: 1.5-2.0) and on the follow-up TEE study the left atrial thrombus resolved in 10 (71%). There were no thromboembolic events or major hemorrhagic complications in these patients, so it was concluded that low-intensity warfarin therapy is efficacious in treating LAT formation in patients with NVAF.

Adult↗

Evaluation of left atrial function by the functional volume change curve derived from Doppler flow spectra.

The objective of this study was to clarify the left atrial (LA) reservoir and booster pump function in patients with left ventricular (LV) diastolic dysfunction. To determine LA reservoir and booster pump function, a new algorithm to determine LA functional volume change curve (FVC) was developed from Doppler flow spectra of pulmonary venous flow and LV inflow by transthoracic echocardiography in 110 patients. Patients were classified into normal (N), and abnormal (AB) and pseudonormal (PN) groups on the basis of their Doppler flow patterns. From the indices of FVC, atrial reservoir volume (ARV), passive emptying volume (PEV) and active emptying volume (AEV) were obtained. ARV/stroke volume (SV) was increased in the AB group, but decreased in the PN group compared with N (N, 0.61+/-0.09; AB, 0.73+/-0.10; PN, 0.52+/-0.13, p<0.05). PEV/SV was significantly decreased in AB, but increased in PN compared with N (N, 0.27+/-0.07; AB, 0.19+/-0.07; PN, 0.31+/-0.18, p<0.05). AEV/SV was significantly increased in AB, but decreased in PN compared with N (N, 0.41+/-0.08; AB, 0.56+/-0.10; PN, 0.26+/-0.19, p<0.05). Thus, in patients with an abnormal relaxation pattern, the LA reservoir and booster pump function are augmented, but in patients with a pseudonormal pattern, both LA reservoir and booster pump function are deteriorated, suggesting a vulnerability to pulmonary congestion.

Adult↗

Analysis of measles virus binding sites of the CD46 gene in patients with subacute sclerosing panencephalitis.

Measles virus (MV) binding sites of the CD46 gene were sequenced in patients with subacute sclerosing panencephalitis (SSPE) and in controls. There were 3 novel polymorphisms, including C/T at nucleotide position 38 (C/T38), G/A at position 176 (G/A176), and C/T at position 453 (C/T453), at allele frequencies of.97:.03, .99:.01, and.97:.03, respectively. The G/A176 polymorphism causes an Arg/Gln amino acid change within the essential binding sites of MV, whereas the C/A38 polymorphism causes a Ser/Phe change outside the MV binding sites. The C/T453 polymorphism does not produce an amino acid change. Two of the 40 SSPE patients and 2 of the 32 controls had both C/T38 and C/T453 polymorphisms in heterozygous patterns. One control subject, but no SSPE patients, had the G/A176 polymorphism in a heterozygous pattern. Thus, it is not likely that CD46 gene alteration has a role as a host susceptibility factor in the development of SSPE.

Adolescent↗

Influence of astigmatism on multifocal and monofocal intraocular lenses.

PURPOSE: To examine the influence of astigmatism on the visual acuity of patients with multifocal and monofocal intraocular lenses. METHODS: Thirty eyes of 30 patients who underwent five-zone refractive multifocal intraocular lens implantation and 30 eyes of 30 age-matched patients who had monofocal intraocular lens implantation were included. The visual acuities of these patients at 5.0, 3.0, 2.0, 1.0, 0.7, 0.5, and 0.3 m were measured by means of an all-distance vision tester after addition of a cylindrical lens of 0, 0.5, 1.0, 1.5, 2.0, and 2.5 diopters. RESULTS: Mean visual acuity at all distances decreased in proportion to the diopters of astigmatism in both the multifocal and monofocal intraocular lens groups. When astigmatism was 0.5, 1.0, or 1.5 diopters, distance visual acuity in the multifocal group was significantly worse than that in the monofocal group; with astigmatism of 2.0 diopters or more, intermediate visual acuity was also worse in the multifocal group. In contrast, near visual acuity in the multifocal group was significantly better than that in the monofocal group at all astigmatic diopters. When astigmatism was within 1.0 diopter, visual acuity in the multifocal group reached 20/29 at distance and 20/50 at near. Mean contrast sensitivity was also worse in the multifocal group than in the monofocal group. CONCLUSIONS: Both distance and intermediate visual acuity deterioration caused by astigmatism was greater with a multifocal intraocular lens than with a monofocal intraocular lens, whereas near visual acuity was better with the multifocal intraocular lens. When astigmatism was within 1.0 diopter, eyes with a multifocal intraocular lens achieved good visual acuity at both distance and near.

Accommodation, Ocular↗

Changes in anterior chamber angle width and depth after intraocular lens implantation in eyes with glaucoma.

OBJECTIVE: To examine the changes in anterior chamber angle width and depth induced by intraocular lens (IOL) implantation in eyes with angle-closure glaucoma (ACG), in eyes with open-angle glaucoma (OAG), and in eyes with no evidence of glaucoma or ocular hypertension. DESIGN: A comparative, nonrandomized, interventional study. PARTICIPANTS: Seventy-seven eyes with ACG, 73 eyes with OAG, and 74 control eyes undergoing cataract extraction and IOL implantation. INTERVENTION: All eyes underwent phacoemulsification and soft acrylic IOL implantation. MAIN OUTCOME MEASURES: The angle width and depth of the anterior chamber were measured using a Scheimpflug videophotography system before surgery, and at 1 week and at 1, 3, 6, 9, and 12 months after surgery. RESULTS: Before surgery, the mean anterior chamber angle width and depth in the ACG group was less than that in either the OAG or control groups by approximately 10 degrees in angle width and 1.0 mm in depth (P < 0.0001). After cataract extraction and IOL implantation, the angle width and depth increased significantly in all three groups (P < 0.0001). Although the width and depth in the ACG group were still smaller than that in the other groups, the differences decreased to 2 degrees for angle width and 0.3 mm for depth. In addition, no significant differences were found in these values between the OAG and control groups before or after surgery. Furthermore, no significant changes were observed in the angle width or depth in any of the three groups throughout the postoperative observation period. As expected, the mean preoperative intraocular pressure (IOP) in the ACG and OAG groups was higher than that in the control group. After cataract surgery, however, the mean IOP decreased significantly and was almost the same in all three groups at 1, 6, and 12 months after surgery. CONCLUSIONS: The width and depth of the anterior chamber angle in eyes with ACG increased significantly after cataract extraction and IOL implantation and became similar to that in eyes with OAG and that in normal eyes, which may lead to the decrease in IOP seen in the postoperative period. No significant changes were observed in angle width and depth in any of the three groups after surgery.

Aged↗

Novel polymorphism in the coding region of the IL-13 receptor alpha' gene: association study with atopic asthma in the Japanese population.

Interleukin (IL)-4 and IL-13 play key roles in the development of atopic asthma. The IL-13 receptor (R) alpha' chain is a component of both IL-4R and IL-13R complexes. By screening the whole coding region of the IL-13Ralpha' gene for polymorphisms, we identified a new polymorphism at nucleotide position 1050 from the ATG start codon. The allelic frequency of the C/T polymorphism in the Japanese population was found to be 0.97:0.03. Because of the low frequency of the T allele, the association study failed to indicate any significant association between this polymorphism and atopic asthma in the Japanese population. Further studies are required in other racial groups with higher frequencies of this polymorphism to elucidate the association.

Alleles↗

Lack of association between CD28/CTLA-4 gene polymorphisms and atopic asthma in the Japanese population.

Atopic asthma occurs in genetically susceptible individuals in the presence of environmental factors. Recently, the costimulation signal from CD80-CD86 to CD28/CTLA-4 has been suggested to play an important role in the development of atopic asthma. In the present study, we analyzed three polymorphic regions within the CTLA-4 gene, an A/G substitution in exon 1 position 49, a C/T base exchange in the promoter position -318 and an (AT)n repeat polymorphism in the 3'-untranslated region of exon 4, and a CD28 gene polymorphism with a T/C substitution in intron 3 position +17 in 120 patients with atopic asthma and 200 normal controls. The polymorphism frequencies of CTLA-4/CD28 genes in patients did not differ from those in normal controls. Thus, the present study was unable to reveal any association between CTLA-4/CD28 gene polymorphisms and atopic asthma in the Japanese population.

Abatacept↗

Intraocular lens tilt and decentration, anterior chamber depth, and refractive error after trans-scleral suture fixation surgery.

OBJECTIVES: To compare the extent of intraocular lens (IOL) tilt and decentration, as well as the anterior chamber depth after trans-scleral suture IOL fixation after either secondary out-of-the-bag or primary in-the-bag IOL implantation. DESIGN: Retrospective, comparative, nonrandomized, interventional study. PARTICIPANTS: Fifty-two eyes that underwent scleral suture fixation were compared with 51 eyes that underwent secondary out-of-the-bag implantation and 50 eyes that underwent in-the-bag implantation. INTERVENTION: One-piece polymethyl methacrylate IOL implantation by three different techniques. MAIN OUTCOME MEASURES: The tilt angle and decentration length of the IOL, as well as the anterior chamber depth, were measured by the Scheimpflug videophotography system. The spherical equivalent error from the predicted value was also examined. RESULTS: The mean tilt angle in the scleral suture fixation group was significantly greater than that in either the out-of-the-bag or the in-the-bag implantation group (P<0.0001). The mean decentration length was also largest in the suture group, followed by the out-of-the-bag group and the in-the-bag group (P<0.0001). The anterior chamber depth in the suture group and the out-of-the-bag group was significantly smaller than that in the in-the-bag group (P<0.0001). The spherical equivalent error in the suture group and the out-of-the-bag group was also greater than that in the in-the-bag group (P<0.0001). CONCLUSIONS: The extent of both tilt and decentration after scleral suture fixation was greater than that observed after either out-of-the-bag or in-the-bag implantation. The anterior chamber depth with the sutured or out-of-the-bag fixated IOL was shallower than that with the in-the-bag fixated IOL, which resulted in a significant myopic shift.

Adolescent↗

Intraocular lens tilt and decentration after implantation in eyes with glaucoma.

PURPOSE: To evaluate the extent of intraocular lens (IOL) tilt and decentration after implantation in eyes with glaucoma. SETTING: Hayashi Eye Hospital, Fukuoka, Japan. METHODS: Fifty-two eyes of 52 patients with glaucoma and 52 control eyes from 52 age-matched patients had phacoemulsification with IOL implantation. Twenty-nine eyes had closed-angle glaucoma (CAG), and the other 23 eyes had open-angle glaucoma (OAG). The extent of IOL tilt and decentration was measured using Scheimpflug videophotography 1 week and 1, 3, 6, 9, and 12 months postoperatively. RESULTS: The mean tilt angle in the glaucoma group was significantly greater than in the control group throughout the follow-up. Mean decentration length was also greater in the glaucoma than in the control group, but the difference was not significant. The incidence of eyes showing a marked tilt (greater than 5 degrees) or decentration (greater than 0.5 mm) was higher in the glaucoma than in the control group. The mean tilt angle and the incidence of eyes showing a marked tilt or decentration in the CAG group were significantly greater than in the control group. CONCLUSION: Intraocular lens tilt was more extensive in the eyes with glaucoma, especially in those with CAG, than in normal eyes. Decentration was also greater in the glaucoma groups than in the control group, although the differences were not significant.

Aged↗

Repetitive coxsackievirus infection induces cardiac dilatation in post-myocarditic mice.

The relation between mycarditis and dilated cardiomyopathy (DCM) is controversial. To clarify the pathogenic mechanism of these diseases, the present study examined the effect of repetitive inoculation with coxsackievirus B3 (CVB3) in post-myocarditic mice. Inbred 3-week-old A/J mice were inoculated intraperitoneally with CVB3 (Nancy strain; 2x10(4) plaque-forming units) and reinfected in the same manner with CVB3 at 40 weeks (3W+/40W+). All mice were killed at 42 weeks old. The weight of the hearts of the 3W+/40W+ group were significantly increased compared with those of the 3W-/40W+ group, and both the heart weight/body weight and lung weight/body weight ratios of the 3W+/40W+ group were also significantly increased over those of the 3W-/40W- group, although the levels of serum neutralizing antibody titers were significantly increased in the 3W+/40W+ group over the level of the other groups. No increase in inflammatory cell infiltration or fibrosis progression was observed in the 3W+/40W+ group relative to the 3W+/40W- group, but the second inoculation resulted in a significant left ventricular dilatation and in left and right ventricular free wall thinning (3.31+/-0.20 mm vs 2.61+/-0.19 mm, p<0.05; 0.54+/-0.09 mm vs 0.72+/-0.16 mm, p<0.05, respectively). The sarcomere length was also significantly increased in the 3W+/40W+ group compared with that of the other groups, as determined by electron microscopy. Degenerative or necrotic areas in the infected hearts were not stained with anti-mouse IgG antibody, but were stained, only in 3W+/40W+ mice, with anti-mouse IgM antibody. The concentrations of TNF-alpha in the hearts of the 3W+/40W+ group were increased significantly over those of the 3W+/40W- group. Repetitive CVB3 infection produced cardiac dilatation without inflammatory cell infiltration in post- myocarditic mice. Autoimmunity mediated by the circulation of certain antibodies (eg, antibodies against the CVB3 genome or a CVB3-related protein) may be part of the pathogenic mechanism for this phenomenon. Thus, repetitive virus infection might contribute to the pathogenesis of cardiac dilatation.

Animals↗