[Circulating bone marrow-derived stem cells in patients with polypoidal choroidal vasculopathy]

PURPOSE

The current study was designed to investigate the role of circulating bone marrow (BM)-derived stem cells in the pathogenesis of polypoidal choroidal vasculopathy (PCV), a distinct type of neovascular age-related macular degeneration (AMD).

METHODS

Thirty one clinically documented PCV patients were enrolled. Circulating BM-derived stem cells were collected from the patients' peripheral blood and cultured. Colony forming capacity (Hill assay) and migration activity (Boyden chamber system) were examined and analyzed.

RESULTS

Colony forming units (CFU-Hill) were significantly fewer in bilateral PCV patients than in unilateral PCV patients. CFU-Hill was impaired in patients with larger (> 5000 microm) PCV lesions compared with patients with smaller PCV lesions. Migration activity of BM-derived stem cells was also reduced significantly in the bilateral PCV patients than in the unilateral PCV patients.

CONCLUSIONS

Similar to CNV associated with AMD, impaired functional activity of circulating BM-derived stem cells was observed in PCV patients with bilateral or larger lesions. Circulating BM-derived stem cells may have a role in the pathogenesis of PCV.

A case of Evans syndrome combined with systemic lupus erythematosus successfully treated with rituximab

Evans syndrome is a rare autoimmune disorder with unknown aetiology. Although corticosteroids and/or intravenous immunoglobulin (IVIG) are commonly used in its treatment, no standard strategy has been established. We report here a 44-year-old male with refractory Evans syndrome combined with systemic lupus erythematosus (SLE) who responded well to rituximab. He was admitted to our hospital with severe bleeding caused by worsening of Evans syndrome. Despite treatment with a high-dose corticosteroid and IVIG, his thrombocytopaenia and haemolytic anaemia did not improve. We started rituximab at a dose of 375 mg/m(2) once a week for a total of two doses. There was significant improvement in his thrombocytopaenia and anaemia 1 month after administration of rituximab. Although the total immunoglobulin G (IgG) level did not change, the titres of platelet-associated IgG (PA-IgG) and of an indirect antiglobulin test (IAT) decreased under the treatment with rituximab. It is suggested that rituximab would be a powerful candidate in the treatment of refractory Evans syndrome by depleting abnormal clone-producing autoantibody.

Circulating hematopoietic stem cells in patients with choroidal neovascularization secondary to pathologic myopia

BACKGROUND

Emerging evidences suggest that circulating hematopoietic stem cells (HSCs) affect the pathogenesis of choroidal neovascularization (CNV), however, the roles of HSCs in CNV remain unclear in human population. The current study was designed to investigate the role of HSCs in the pathogenesis of CNV secondary to pathologic myopia (PM).

METHODS

We clinically documented 78 patients with CNV in PM, and 35 of 78 patients and 28 age-matched controls were experimentally analysed. Functional analyses of HSCs were performed using an ex vivo culture system.

RESULTS

We disclosed colony-forming units of endothelial cell (CFU-EC) were markedly lower in patients with bilateral CNV compared to those with unilateral CNV (13.8+/-3.7 vs 45.9+/-7.8, P<0.001). Systemic characteristics between both groups showed no significant difference. To identify local ocular factors that may affect the occurrence of CNV, clinical parameters were compared with the following groups in all enrolled subjects: eyes with CNV vs without CNV in unilateral affected patients, and primary affected eyes vs secondary affected eyes in patients with bilateral CNV. However, no statistically significant factors were identified in any of the groups.

CONCLUSIONS

Circulating HSCs may play a role in the bilateral involvement of CNV in PM patients as one of the systemic factors. Further prospective and longitudinal studies are required.

Activation of bone marrow-derived microglia promotes photoreceptor survival in inherited retinal degeneration

The role of microglia in neurodegeneration is controversial, although microglial activation in the retina has been shown to provide an early response against infection, injury, ischemia, and degeneration. Here we show that endogenous bone marrow (BM)-derived microglia play a protective role in vascular and neural degeneration in the retinitis pigmentosa model of inherited retinal degeneration. BM-derived cells were recruited to the degenerating retina where they differentiated into microglia and subsequently localized to the degenerating vessels and neurons. Inhibition of stromal-derived factor-1 in the retina reduced the number of BM-derived microglia and accelerated the rate of neurovascular degeneration. Systemic depletion of myeloid progenitors also accelerated the degenerative process. Conversely, activation of BM-derived myeloid progenitors by systemic administration of both granulocyte colony-stimulating factor and erythropoietin resulted in the deceleration of retinal degeneration and the promotion of cone cell survival. These data indicate that BM-derived microglia may play a protective role in retinitis pigmentosa. Functional activation of BM-derived myeloid progenitors by cytokine therapy may provide a novel strategy for the treatment of inherited retinal degeneration and other neurodegenerative diseases, regardless of the underlying genetic defect.

Circulating hematopoietic stem cells in patients with neovascular age-related macular degeneration

PURPOSE

Circulating hematopoietic stem cells (HSCs) appear to have roles in the formation of choroidal neovascularization (CNV) in age-related macular degeneration (AMD). This study was conducted to investigate whether the number or function of HSCs plays a role in neovascular AMD.

METHODS

Eighty-one patients with neovascular AMD who underwent comprehensive fundus examinations every 3 months were included. The number of CD34(+) HSCs isolated from peripheral blood was counted by flow cytometry. Serum cytokine levels were assessed by enzyme-linked immunosorbent assay. To examine the function of circulating HSCs, mononuclear cells were cultured and then colony forming unit (CFU-EC) and migration were measured.

RESULTS

The number of circulating CD34(+) HSCs was significantly increased in the patients with active CNV without major systemic diseases (stable: 3.8 +/- 0.3 cells/microL, active: 5.5 +/- 0.7 cells/microL, stable versus active: P < 0.05). The number of HSCs correlated positively with the erythropoietin serum level (r = 0.47, P = 0.002). Although there was no significant difference in the CFU-EC between the patients with CNV and the control subjects, a significant decrease of CFU-EC was observed in the patients with bilateral or larger CNV.

CONCLUSIONS

The findings suggest that CD34(+) HSCs may be recruited from bone marrow through a signal from active CNV. Furthermore, HSCs may play a role in the severity of CNV.

Polypoidal choroidal vasculopathy examined with en face optical coherence tomography

BACKGROUND

To study the morphologic features of polypoidal choroidal vasculopathy (PCV) with the use of en face optical coherence tomography (OCT).

METHODS

We reviewed retrospectively 57 eyes of 57 patients with PCV. The macular region was examined with OCT en face planes scanned at different sequential depths, following which detailed scanning was performed of arbitrarily selected longitudinal planes.

RESULTS

In 48 of the cases (84.2%), en face OCT allowed us to detect round protrusions of the retinal pigment epithelium (RPE) that corresponded to the polypoidal lesions seen on indocyanine green angiography (ICGA); the branching vascular networks seen on ICGA often induced slight elevation of the overlying RPE, which typically assumed a geographical shape. In 30 cases (52.6%), branching vascular networks were detected as elevations of the RPE. With en face OCT, serous pigment epithelial detachments, most of which were seen as round protrusions of the RPE, were often accompanied by adjacent smaller round protrusions of the RPE, consistent with polypoidal lesions. These protrusions of the RPE were often fused and typically appeared as a 'snowman'. Subsequent longitudinal examination revealed the polypoidal lesions to be sharp protrusions of the RPE with moderate inner reflectivity. Consistent with the location of the branching vascular network, a highly reflective line was seen often just beneath the slightly elevated reflective line of RPE.

CONCLUSIONS

En face examination using OCT has an advantage in screening lesions of PCV and in examination of the detailed relationship of each component of these lesions.

Central retinal sensitivity measured with the micro perimeter 1 after photodynamic therapy for polypoidal choroidal vasculopathy

PURPOSE

To evaluate central retinal sensitivity and its relation to the symptomatic change noted in central visual disturbance shortly after photodynamic therapy (PDT) in eyes with polypoidal choroidal vasculopathy (PCV).

DESIGN

Retrospective interventional case series.

METHODS

We reviewed retrospectively 20 eyes of 20 patients who underwent PDT for the treatment of subfoveal PCV. Microperimetry in the macular area was performed with Micro Perimeter 1 (MP1) [Nidek, Vigonza, Italy] before and at one, three, and six months after PDT. Forty measurement points were located within the central 10 degree of the macula.

RESULTS

After PDT, although most eyes showed a reduction in exudation, the mean posttreatment visual acuity did not change significantly. At one month after PDT, however, retinal sensitivities within the central 2 degree, 6 degree, and 10 degree fields, which were 3.6 +/- 3.1, 5.1 +/- 3.4, and 6.2 +/- 3.6 dB [decibels] at baseline, improved to 5.9 +/- 3.8 (P = .003), 7.1 +/- 3.6 (P = .003), and 8.1 +/- 3.5 dB (P = .004). At one month after treatment, 14 patients (70%) noted subjective improvement of the central visual disturbance and mean retinal sensitivity within the central 2 degree, 6 degree, and 10 degree fields had improved more than 2 dB in 11, 10, and eight eyes, respectively. At three and six months after PDT, however, postoperative improvement of the retinal sensitivities was diminished.

CONCLUSIONS

Retinal sensitivity in the macular area of eyes with subfoveal PCV improved shortly after PDT, and may account, at least in part, for the immediate subjective improvement in central vision after PDT.

Polypoidal choroidal vasculopathy appearing as classic choroidal neovascularisation on fluorescein angiography

AIMS

To study the visual prognosis and ocular characteristics of eyes with polypoidal choroidal vasculopathy (PCV) that appear to have classic choroidal neovascularisation (CNV) on fluorescein angiography (FA).

METHODS

The authors reviewed retrospectively 38 eyes with PCV that appear to have classic CNV on FA. Lesions were examined with indocyanine green angiography, FA and optical coherence tomography (OCT).

RESULTS

In all cases OCT showed subretinal material with moderate reflectivity that corresponded in location to classic CNV. At the final visit, the subretinal material resolved completely in 14 eyes (36.8%, resolved group), but resolved only incompletely in 24 eyes (63.2%, persisted group) after photodynamic therapy (PDT). Mean (standard deviation) visual acuity in the resolved group (0.35 (0.41) in log MAR) was significantly better than that in the persisted group (0.84 (0.24)) at the final visit (p<0.001). The subretinal material seen before treatment was more frequently seen in subfovea in the persisted group (87.5% vs 42.9%, p = 0.007). Also, this material was located adjacent to polypoidal lesions more often in the resolved group (92.9% vs 58.3%, p = 0.030).

CONCLUSIONS

Eyes with PCV sometimes show classic CNV with subretinal material apparent on OCT, and PCV is thus attributed to type 2 CNV or to pure fibrinous tissue without CNV. Visual prognosis in eyes with type 2 CNV is poor, and although it is difficult to discriminate type 2 CNV from pure fibrin deposition before treatment, type 2 CNV is seen more often in the subfovea and is typically separate from the polypoidal lesions.

Pigment epithelial detachment in polypoidal choroidal vasculopathy

PURPOSE

To study the morphological features of serosanguineous pigment epithelial detachments (PEDs) with accompanying polypoidal lesions in eyes with polypoidal choroidal vasculopathy (PCV).

DESIGN

Retrospective observational case series.

METHODS

For this observational case study, we retrospectively reviewed 93 consecutive eyes of 85 patients with PCV. The lesions in eyes with PCV were examined with indocyanine green angiography (IA) and optical coherence tomography (OCT).

RESULTS

Of 93 eyes with PCV, 51 eyes (55%) had serous or hemorrhagic PEDs. Of these 51 eyes, a notch in the PED was found in 27 eyes (53%) by angiography, most of which showed polypoidal lesions by IA that corresponded in location to the notch observed by angiography. Polypoidal lesions were detected outside the PED in one eye (2%), at the margin of the PED in 33 eyes (65%), and inside the PED in 12 eyes (24%). OCT revealed that PED had a notch observed tomographically in 29 eyes (57%), most of which corresponded in location to polypoidal lesions seen by IA. In eight eyes, polypoidal lesions, which were adherent to the inner surface of the serous PED, appeared to be detached from the Bruch membrane and the choroid.

CONCLUSIONS

Polypoidal lesions are located at the margin of PED and make a notch in the accompanying PED that is visible by angiography and tomographically. When the polypoidal lesions have increased exudate, the fluid from the lesions infiltrates under the polypoidal lesions themselves, which results in the lesions detaching from the Bruch membrane and appearing to be located inside the PED.

SWI/SNF complex is essential for NRSF-mediated suppression of neuronal genes in human nonsmall cell lung carcinoma cell lines

Mammalian chromatin remodeling factor, SWI/SNF complex contains a single molecule of either Brm or BRG1 as the ATPase catalytic subunit. Here, we show that the SWI/SNF complex forms a larger complex with neuron-restrictive silencer factor (NRSF) and its corepressors, mSin3A and CoREST, in human nonsmall cell lung carcinoma cell lines. We also demonstrate that the strong transcriptional suppression of such neuron-specific genes as synaptophysin and SCG10 by NRSF in these non-neural cells requires the functional SWI/SNF complex; these neuronal genes were elevated in cell lines deficient in both Brm and BRG1, whereas retrovirus vectors expressing siRNAs targeting integral components of SWI/SNF complex (Brm/BRG1 or Ini1) induced expression of these neuronal genes in SWI/SNF-competent cell lines. In cell lines deficient in both Brm and BRG1, exogenous Brm or BRG1 suppressed expression of these neuronal genes in an ATP-dependent manner and induced efficient and specific deacetylation of histone H4 around the NRSF binding site present in the synaptophysin gene by a large complex containing the recruited functional SWI/SNF complex. Patients with Brm/BRG1-deficient lung carcinoma have been reported to carry poor prognosis; derepression of NRSF-regulated genes including these neuron-specific genes could contribute to enhance tumorigenicity and also would provide selective markers for Brm/BRG1-deficient tumors.

Acceleration of the formation of cultured epithelium using the sonic hedgehog expressing feeder cells

Sonic hedgehog (Shh) regulates the principal possesses in many developmental stages, including the epithelial-mesenchymal interaction. The extraordinary acceleration of signaling by Shh is responsible for the development of human basal cell carcinomas and trichoepitheliomas; they might originate from the very immature keratinocytes, including the stem cells. We tried to utilize the mitogenic effect of Shh to accelerate the formation of cultured epithelium, which is already used in the medical field practically. To this end, we transfected shh cDNA into a Swiss-3T3 cell line, widely used as a feeder for keratinocytes, and established a Shh expressing cell line. The lethally irradiated Shh expressing feeder cells remarkably accelerated the growth of keratinocyte colonies obtained from the human neonatal foreskin, and the formation of well-stratified cultured epithelium, which is rich in immature small keratinocytes, expressing cytokeratin 14. This acceleration was suppressed by the addition of cyclopamine, a specific inhibitor of Shh signaling. These data indicate that the Shh is a promising mitogen to improve the technology for cultured epithelium formation.

Genetic analysis of a variant luteinizing hormone in an infertile woman

In a woman with infertility and an endometrial polyp, we analyzed the nucleotide sequence of the beta-subunit of her luteinizing hormone which showed anomalous immunogenecity in that it was recognized by time resolved-fluoroimmunoassay but not by immunoradiometric assay. The sequence analysis showed two substitutional mutations of beta-subunit Trp (TGG) to Arg (CGG) and Ile (ATC) to Thr (ACC). The variant luteinizing hormone might have had some relation to the infertility and the endometrial polyp. been described [2, 4, 13-15]. Although the role of the variant LH is still unclear, it has different biologicl activity as compared to normal LH and may play a role in causing infertility, menstrual disorder, endometriosis and spontaneous miscarriage [1, 3, 4, 9, 10, 17]. We now report a study of the DNA sequence of beta-subunit of anomalous LH in an infertile patient with an endometrial polyp.

An evaluation of the intraoperative transit time measurements of coronary bypass flow

OBJECTIVE

The intraoperative measurement of the coronary bypass flow enables the identification of technical errors while the sternum is still open. The transit-time flow method is able to effectively measure the internal thoracic artery graft flow. The aim of the present study was to analyze the factors which affected the bypass flow rate.

METHODS

We measured the blood flow of 291 in situ internal thoracic artery (ITA) and 190 saphenous vein (SV) grafts constructed in 171 patients undergoing coronary artery bypass grafting from December 1996 to March 2000 using this method during the surgery. All patients underwent postoperative coronary angiography before the patients were discharged. The blood flow rate of all bypass grafts constructed was assessed after the patients were weaned from cardiopulmonary bypass.

RESULTS

The mean flow rate of all ITA grafts was 65.1+/-36.7 ml/min and that of all SV grafts was 56.4+/-29.9 ml/min. According to analyses using correlation tests, the graft flow was found to significantly correlate with the grafted perfusion areas and the diameter of the bypassed coronary arteries. However, no significant difference was observed between the flow rates of the ITA grafts with and without stenosis or string phenomenon, but significant (P<0.0001) correlation was observed between the occurrence of a string sign and the degree of proximal stenosis of the recipient coronary artery. Regarding SV grafts, the mean flow rate of occluded grafts (29.2+/-20.5 ml/min) was significantly (P<0.0001) less than non-occluded grafts (56.4+/-29.9 ml/min).

CONCLUSIONS

The bypass flow was affected by such a large number of factors that only measuring the bypass flow rate could not sufficiently predict either stenosed or narrowed grafts. However, ITA grafts bypassed to the coronary arteries with less stenosis were shown to more easily become narrowed.

Electron paramagnetic resonance study on free radical scavenging and/or generating activity of dopamine-4-O-sulfate

The free radical scavenging and/or generating activity of dopamine-4-O-sulfate was examined and compared with that of dopamine. In humans, dopamine mostly exists in two isomeric forms of sulfate ester conjugates as metabolites; i.e., dopamine-3-O-sulfate and dopamine-4-O-sulfate in the circulation. Dopamine is generally believed to be oxidized by molecular oxygen or another reactive oxygen species under physiological conditions, to form oxidized dopamine derivatives that are cytotoxic. However, it is not known whether dopamine conjugates are generated on interaction with reactive oxygen species or not. In the present study, we measured the susceptibility to oxidization of dopamine-4-O-sulfate by using electron paramagnetic resonance (EPR) spectroscopy and optical absorption spectrometry. Dopamine was easily oxidized and dopamine-derived radicals appeared, whereas dopamine-4-O-sulfate was not oxidized under physiological conditions. Furthermore, dopamine-4-O-sulfate did not react with a strong oxidizing agent, sodium periodate. These results suggest that dopamine-4-O-sulfate has resistance against autoxidation, and seems to be a stable metabolite of dopamine.

Structure of Bombyx mori silk fibroin before spinning in solid state studied with wide angle x-ray scattering and (13)C cross-polarization/magic angle spinning NMR

The structure of a crystalline form of Bombyx mori silk fibroin, commonly found before the spinning process (known as silk I), has been proposed as a repeated beta-turn type II-like structure by combining data obtained from solid-state two dimensional spin-diffusion nuclear magnetic resonance and rotational-echo double-resonance (T. Asakura et al., J Mol Biol, in press). In this paper, the WAXS pattern of alanine-glycine alternating copolypeptide, (Ala-Gly)(15) with silk I form which was used for a silk I model of B. mori silk fibroin was observed. The pattern calculated with the silk I model proposed by us is well reproduced the observed one, indicating the validity of the proposed silk I model. In addition, two peptides of the other repeated sequences which contain Tyr or Val residues in the silk fibroin,23 were synthesized; (Ala-Gly-Tyr-Gly-Ala-Gly)(5) and (X-Gly)(15) where X is Tyr for the 7th, 15th and 23th residues, and Val for the 11th residue and Ala for other residues. There are no sharp peaks in the WAXS patterns, and therefore both samples are in the non-crystalline state. This is in agreement with the (13)C CP/MAS NMR result, where the conformation is mainly random coil.

A repeated beta-turn structure in poly(Ala-Gly) as a model for silk I of Bombyx mori silk fibroin studied with two-dimensional spin-diffusion NMR under off magic angle spinning and rotational echo double resonance

The structure of a crystalline form of Bombyx mori silk fibroin, commonly found before the spinning process (known as silk I), was proposed by combining data obtained from two-dimensional spin-diffusion nuclear magnetic resonance under off magic angle spinning, rotational-echo double-resonance (REDOR), previously reported X-ray diffraction analyses and 13C NMR chemical shifts. Instead of B. mori silk fibroin with silk I structure, we used the sequential model peptide (Ala-Gly)15. The structure of the sequential model peptide is characterized as silk I after dissolving the peptide in 9 M LiBr and then dialyzing against water. Moreover, 13C or 15N-labeled sites may be introduced easily at any position in (Ala-Gly)(15) by the solid phase synthesis method for these NMR experiments. The torsional angles of (Ala-Gly)15 with silk I structure were determined as (-60(+/-5) degrees, 130(+/-5) degrees ) and (70(+/-5) degrees, 30(+/-5) degrees ) for Ala and Gly residues, respectively. The formation of the intra-molecular hydrogen bonding along the chain was confirmed from REDOR NMR by determination of the inter-atomic distance between the nitrogen and carbon atoms comprising the intra-molecular hydrogen bonding. The structure is named a repeated beta-turn type II-like structure.

Coronary artery bypass grafting within 30 days of an acute myocardial infarction

Early surgical intervention is now often considered for symptomatic patients after an acute myocardial infarction. Conversely coronary artery bypass grafting soon after an acute myocardial infarction poses substantial risks. The present study was performed to evaluate the results of Coronary artery bypass grafting soon after an acute myocardial infarction.

METHODS

From November 1991 to November 1999, 478 consecutive patients underwent coronary artery bypass grafting and 68 of these underwent an operation within 30 days of AMI. The data of these patients were analyzed retrospectively. Univariate and multivariate analyses of many variables were performed regarding operative mortality.

RESULTS

Operative mortality (7.4%) was significantly higher in the patients with an acute myocardial infarction than in the patients without it (0.8%) during the same period as the subjects of this study. Coronary artery bypass grafting without arterial grafts was solely determined to be the predictor of survival. The survival curve demonstrated better long-term results in patients undergoing bypass grafting with arterial grafts than in patients undergoing bypass grafting with venous grafts alone.

CONCLUSIONS

If hemodynamic conditions can not be stabilized, then coronary artery bypass grafting using arterial grafts, when indicated, should be performed even early after AMI.