PubMed Health⌕ Search

Biomedical subjects

Tetsuro Miyata

Publications and source records attributed to Tetsuro Miyata.

At least 19 recordsLinked to original sources
PubMed2006

Spontaneous mesenteric hemorrhage associated with Ehlers-Danlos syndrome.

The vascular type of Ehlers-Danlos syndrome is a genetic disorder of connective tissue and is frequently associated with catastrophic arterial complications. Its surgical treatment is extremely difficult because of the fragility of vessels. This article describes three patients with vascular type of Ehlers-Danlos syndrome who developed mesenteric hemorrhage due to spontaneous arterial rupture. The clinical and molecular characteristics of the disease are briefly reviewed.

Abdominal Cavity↗
PubMed2006

Inflammatory responses involving tumor necrosis factor receptor-associated factor 6 contribute to in-stent lesion formation in a stent implantation model of rabbit carotid artery.

OBJECTIVE: Inflammatory responses are considered to represent a unique property after stent implantation, and we previously demonstrated that inflammatory signaling involving tumor necrosis factor receptor-associated factor 6 (TRAF6) contributes to neointimal formation in a balloon injury model of rabbit carotid artery. The purpose of this study was to examine the role of TRAF6 in in-stent lesion formation after stent implantation in the rabbit carotid artery. METHODS: Rabbit carotid arteries were injured with a 2F Fogarty catheter, and 28 days later, the same arteries were implanted with a 3-mm-diameter Palmaz-Schatz stent. A dominant negative (DN) form of TRAF6 (pME-FLAG-T6deltaRZ5) was then transferred using a plasmid-based electroporation method. Its effects were evaluated compared with the findings in arteries treated with control plasmid (pME-FLAG). RESULTS: Immunostaining with anti-FLAG tag antibody showed that an expression plasmid vector containing the DN-TRAF6 sequence was successfully transferred to the arterial intima and media. Morphometric analyses revealed that the increase of intimal area in in-stent lesions was significantly inhibited by DN-TRAF6 14 days after stent implantation (DN-TRAF6 group, 3.01 +/- 0.25 x 10(5) microm2 vs control group, 4.25 +/- 0.23 x 10(5) microm2, P < .01), and the cell density was increased compared with that in the control group. In the DN-TRAF6 plasmid-treated vessels, cell replication was prevented in both the intima and media, and fewer leukocytes adhered to the luminal surface. Moreover, DN-TRAF6 suppressed macrophage infiltration, activation of proteases, and proteoglycan accumulation in the in-stent intima. CONCLUSIONS: These findings suggest that TRAF6 plays an important role in cell replication, inflammatory cell infiltration, protease activity, and extracellular matrix accumulation that contributes to in-stent lesion development.

Animals↗
PubMed2006

Popliteal arterial aneurysm associated with Klippel-Trénaunay syndrome: case report and literature review.

A 35-year-old woman with Klippel-Trénaunay syndrome developed a popliteal artery aneurysm in the affected extremity. The aneurysm was successfully treated by aneurysmectomy and bypass grafting with autologous saphenous vein. In Klippel-Trénaunay syndrome, angiodysplasia in the venous system is common. However, reports of an arterial aneurysm in a patient with Klippel-Trénaunay syndrome are extremely rare.

Adult↗
PubMed2006

Clinical outcome and complications of temporary inferior vena cava filter placement.

OBJECTIVE: We evaluated the current clinical experience of temporary inferior vena cava (IVC) filter placement and its related complications. METHODS: From January 2000 to December 2005, we enrolled 33 patients (8 men and 25 women) who underwent percutaneous insertion of a temporary IVC filter in the Department of Vascular Surgery of Tokyo University Hospital. Deep vein thrombosis (DVT) was proven in 78.8% of the patients. The indications for filter insertion were contraindication to anticoagulation therapy (9.1%), thrombolytic therapy (12.1%), perioperative prophylactic implantation (84.8%), pregnancy with DVT (3.0%), and prophylactic implantation in the absence of DVT (15.2%). A Neuhaus Protect was used in 13 patients, and an Antheor was used in 20 patients. RESULTS: The mean +/- SD duration of filter placement was 10.6 +/- 7.0 days. There was no case of pulmonary embolism during filter protection and retraction. Filter thrombosis (capture of thrombus) was observed in four patients (12.1%), who then received additional thrombolytic therapy. Thrombi were dissolved by thrombolysis in three, one of whom had replacement with a permanent filter. The thrombus was not dissolved in one patient and was removed under venotomy at the insertion site. Major filter-related complications occurred in nine patients (27.3%), including filter dislocation in four patients (12.1%), catheter fracture in three (9.1%), and catheter-related infection in one (3.0%). In a patient with giant ovarian cancer, the IVC was nearly occluded with massive thrombus around the filter 2 days after operation, and the vena cava was then ligated under open laparotomy. No patients died during filter protection and retraction. CONCLUSIONS: Temporary IVC filters were effective for the prevention of fatal pulmonary embolism. However, our experience of a high incidence of complications related to temporary filters suggests that this device has limited indications and supports the need for innovative design of temporary filters.

Adolescent↗
PubMed2005

Evaluation of cerebral hypoperfusion by nuclear medicine imaging in a patient with Takayasu's arteritis.

In patients with Takayasu's arteritis presenting with cerebrovascular insufficiency, deciding whether and how to perform surgical intervention is difficult. We report successful extra-anatomical cerebrovascular reconstruction in a patient with Takayasu's arteritis involving the aortic arch. A 27-year-old woman was diagnosed with Takayasu's arteritis with occlusion of all three branches of the aortic arch. Single-photon emission computed tomography and positron emission tomography of the brain were useful in assessing the indication and effect of surgical treatment. Right common ilioaxillary artery bypass grafting was performed, and at 18-month follow-up the patient remained symptom-free. Extra-anatomical bypass can be a therapeutic option for surgical management of Takayasu's arteritis with aortic arch involvement.

Adult↗
PubMed2005

Surgical treatment of atypical aortic coarctation complicating Takayasu's arteritis--experience with 33 cases over 44 years.

PURPOSE: This study was conducted to evaluate the long-term outcomes of surgical treatment for atypical aortic coarctation due to Takayasu's arteritis and to elucidate the factors that affected outcome. METHODS: The outcomes of surgical treatment for atypical aortic coarctation complicating Takayasu's arteritis in 33 consecutive patients over the previous 44 years at our institution were reviewed retrospectively. Preoperatively, 29 patients had coarctation proximal to the renal arteries and hypertension in the upper half of the body. Four hospital deaths occurred, and the remaining 29 patients were followed from 0.5 to 42.0 years (median, 17.9 years). The impacts of several risk factors on survival as well as cardiac and vascular events were analyzed. RESULTS: Among 27 initial survivors who had hypertension preoperatively, 15 did not show normalization of blood pressure. The overall cumulative survival and event-free survival rate at 20 years were 62.3% and 58.4%, respectively. Serious long-term complications were anastomotic aneurysms, congestive heart failure, cerebrovascular accident, graft deterioration, abdominal aortic aneurysms, and renal failure. Among several risk factors analyzed, only the presence of postoperative hypertension had an effect on event-free survival. CONCLUSIONS: The long-term survival after surgery for atypical aortic coarctation was satisfactory. However, our study showed that complications associated with cardiovascular system or the operation could occur at any time after surgery; thus, life-long follow-up is mandatory. Further, the absence of normalization of blood pressure after surgery was a poor prognostic factor. Our results demonstrate the need for an intimate preoperative evaluation of renal and carotid artery lesions, which often coexist and may also cause secondary hypertension, to fully manage hypertension by surgery.

Adolescent↗
PubMed2005

Long-term outcome after surgical treatment of arterial lesions in Behçet disease.

OBJECTIVE: Surgical treatment of arterial lesions associated with Behçet disease (BD) is often complicated by graft occlusion and recurrence of aneurysms. The purpose of this study was to clarify the long-term outcome of surgical intervention for arterial involvement in BD. METHODS: Ten patients with BD (9 men, 1 woman) who underwent surgical treatment for arterial aneurysms between 1980 and 2004 were included in the study. The age of patients at the first operation ranged from 36 to 69 years (mean, 50.4 +/- 9.0 years). The mean period between the onset of BD and that of arterial manifestations was 8.0 +/- 5.0 years. We retrospectively reviewed their postoperative courses, including survival, graft occlusion, formation of anastomotic false aneurysms, and the development of aneurysms at different sites. The Kaplan-Meier method was used to calculate the chronologic incidence of complications after surgery. RESULTS: The mean follow-up period was 133 +/- 92 months, ranging from 5 to 285 months. One patient died of rupture of a dissecting aortic aneurysm after undergoing several surgical interventions for multiple aneurysms. There were five graft occlusions among 21 grafts. The cumulative primary graft patency rate in the infrainguinal region was 83.9% at 3 years. Five anastomotic false aneurysms formed among 49 anastomoses between grafts and host arteries. The overall cumulative incidence of formation of anastomotic pseudoaneurysm was 12.9% at 5 and 10 years. All of them formed within 18 months after surgery. Development of new aneurysms in different arteries was observed in two patients. CONCLUSIONS: Early occurrence of anastomotic false aneurysm is characteristic of BD. Further investigation is necessary to establish effective postoperative treatment.

Anastomosis, Surgical↗
PubMed2005

Clinical implication of plasma level of soluble fibrin monomer-fibrinogen complex in patients with abdominal aortic aneurysm.

OBJECTIVE: We prospectively studied the clinical implication of plasma level of soluble fibrin monomer (FM)-fibrinogen complex, a recently established molecular marker reflecting thrombin activity, in patients with abdominal aortic aneurysm (AAA) undergoing elective aortic repair. METHODS: The study included 49 patients who underwent elective aneurysm repair using a gelatin-sealed or nonimpregnated Dacron prosthesis. Plasma level of soluble FM-fibrinogen complex was measured before surgery and on days 1, 3, 5, 7, and 10 postoperatively by latex agglutination assay utilizing monoclonal antibody IF-43. Plasma levels of thrombin-antithrombin complex (TAT), D-dimer, alpha2-plasmin inhibitor-plasmin complex (PIC), and fibrinogen were also evaluated. RESULTS: The preoperative level of soluble FM-fibrinogen complex showed variation in the degree of hemostatic activation, with fair correlations with TAT (r = 0.509, P < .001), D-dimer (r = 0.521, P < .001), and PIC (r = 0.579, P < .001). The patients with greater intraoperative blood loss (> or = 800 mL) showed a significantly elevated plasma level of soluble FM-fibrinogen complex preoperatively compared with those with less intraoperative blood loss (P = .009). Its postoperative fluctuation showed a similar pattern to that of TAT, reflecting the time course of coagulation activity. Gelatin impregnation of the Dacron vascular graft did not seem to influence the postoperative systemic coagulation mechanism. CONCLUSIONS: The results indicated that soluble FM-fibrinogen complex appears to be a useful diagnostic molecular marker to assess the activity of the coagulation system, and that its preoperative level may serve as a potential risk factor for intraoperative hemorrhagic diathesis in patients undergoing elective AAA repair.

Aged↗
PubMed2005

NO-1886 (ibrolipim), a lipoprotein lipase activator, increases the expression of uncoupling protein 3 in skeletal muscle and suppresses fat accumulation in high-fat diet-induced obesity in rats.

Although the lipoprotein lipase (LPL) activator NO-1886 shows antiobesity effects in high-fat-induced obese animals, the mechanism remains unclear. To clarify the mechanism, we studied the effects of NO-1886 on the expression of uncoupling protein (UCP) 1, UCP2, and UCP3 in rats. NO-1886 was mixed with a high-fat chow to supply a dose of 100 mg/kg to 8-month-old male Sprague-Dawley rats. The animals were fed the high-fat chow for 8 weeks. At the end of the administration period, brown adipose tissue (BAT), mesenteric fat, and soleus muscle were collected and levels of UCP1, UCP2, and UCP3 messenger RNA (mRNA) were determined. NO-1886 suppressed the body weight increase seen in the high-fat control group after the 8-week administration (585 +/- 39 vs 657 +/- 66 g, P < .05). NO-1886 also suppressed fat accumulation in visceral (46.9 +/- 10.4 vs 73.7 +/- 14.5 g, P < .01) and subcutaneous (43.1 +/- 18.1 vs 68.9 +/- 18.8 g, P < .05) tissues and increased the levels of plasma total cholesterol and high-density lipoprotein cholesterol in comparison to the high-fat control group. In contrast, NO-1886 decreased the levels of plasma triglycerides, nonesterified free fatty acid, glucose, and insulin. NO-1886 increased LPL activity in soleus muscle (0.082 +/- 0.013 vs 0.061 +/- 0.016 mumol of free fatty acid per minute per gram of tissue, P < .05). NO-1886 increased the expression of UCP3 mRNA in soleus muscle 3.14-fold (P < .01) compared with the high-fat control group without affecting the levels of UCP3 in mesenteric adipose tissue and BAT. In addition, NO-1886 did not affect the expression of UCP1 and UCP2 in BAT, mesenteric adipose tissue, and soleus muscle. In conclusion, NO-1886 increased the expression of UCP3 mRNA and LPL activity only in skeletal muscle. Therefore, a possible mechanism for NO-1886's antiobesity effects in rats may be the enhancement of LPL activity in skeletal muscle and the accompanying increase in UCP3 expression.

Adipose Tissue↗
PubMed2005

Mitogen-activated protein kinases regulate platelet-activating factor-induced hyperpermeability.

OBJECTIVE: The authors tested the hypothesis that p42/44- (ERK-1/2) and/or p38-mitogen-activated protein kinases (MAPK) are in vivo regulatory elements in the platelet-activating factor (PAF) activated signaling cascade that stimulates microvascular hyperpermeability. METHODS: FITC-dextran 70 was used as the macromolecular tracer for microvascular permeability in the mouse mesenteric fat tissue. Interstitial integrated optical intensity (IOI) was used as an index of permeability. RESULTS: An application of 10(-7) M PAF increased IOI from 23.1 +/- 3.6 to 70.8 +/- 7.4 (mean +/- SEM). Inhibition of ERK-1/2 with 3 microM and 30 microM AG126 reduced IOI to 32.3 +/- 2.5. Similarly, inhibition of p38-MAPK with 6 nM, 60 nM and 600 nM SB203580 lowered IOI to 29.1 +/- 2.4. CONCLUSIONS: The results demonstrate that ERK-1/2 and p38MAPK participate in the signaling cascade that regulates PAF-induced microvascular hyperpermeability in vivo.

Animals↗
PubMed2004

Gelatin hydrogel microspheres enable pinpoint delivery of basic fibroblast growth factor for the development of functional collateral vessels.

BACKGROUND: Various growth factors promote collateral vessel development and are regarded as promising for the treatment of vascular occlusive diseases. However, an efficacious delivery system for them has yet to be established. We devised a strategy to augment functional collateral vessels by using acidic gelatin hydrogel microspheres (AGHMs) incorporating basic fibroblast growth factor (bFGF). The aim of the present study was to investigate the hypothesis that by intra-arterial (IA) administration of bFGF-impregnated AGHMs, bFGF could be delivered from AGHMs trapped in distal small-diameter vessels and thereby induce functional collateral vessels with an assured blood supply through the process of arteriogenesis. METHODS AND RESULTS: Various sizes of AGHMs (3 mg) incorporating 125I-labeled bFGF were injected into the left internal iliac artery of a rabbit model of hindlimb ischemia. Less than 50% of radioactivity accumulated in the ischemic hindlimb after injection of AGHMs that were 10 mum in diameter, whereas approximately 80% of radioactivity was counted in the ischemic limb after administration of 29- or 59-microm-diameter AGHMs. Calf blood pressure ratio and the ratio of regional blood flow of the bilateral hindlimbs immediately before and after IA administration of 29-microm-diameter AGHMs showed no significant change. Then we evaluated the function of the developed collateral vessels 28 days after IA administration of bFGF-impregnated, 29-microm-diameter AGHMs. IA administration of bFGF-impregnated AGHMs induced marked collateral vessel improvement compared with IA administration of phosphate buffered saline-treated AGHMs and intramuscular administration of bFGF-impregnated AGHMs. CONCLUSIONS: IA administration of bFGF-impregnated, 29-microm-diameter AGHMs strongly induced functional collateral vessels without worsening ischemia, indicating the possible therapeutic usefulness of this approach.

Animals↗
PubMed2004

Inflammatory signaling pathway containing TRAF6 contributes to neointimal formation via diverse mechanisms.

OBJECTIVE: The purpose of this study was to investigate the contribution of inflammatory signaling containing tumor necrosis factor receptor-associated factor 6 (TRAF6) to neointimal formation in a balloon injury model of rabbit carotid artery. METHODS: Male Japanese white rabbits fed a normal diet were used. We transferred the dominant negative (DN) form of TRAF6 to a rabbit carotid artery that was subjected to balloon injury by in vivo electroporation method, and then evaluated its effect on intimal lesion formation after balloon injury. RESULTS: An expression plasmid vector containing the TRAF6 DN sequence was successfully transferred to arterial wall cells, and its inhibitory effect on inflammatory signaling was confirmed by the marked suppression of nuclear factor-kappaB (NFkappaB) activity after injury. Morphometric analyses revealed significant inhibition of intimal lesion formation at 7 days after injury. Cell replication and accumulation of macrophages in the media were significantly decreased, and apoptosis was enhanced on day 2. Cell migration to the intima was suppressed on day 4. Extracellular signal-regulated kinase1/2 (ERK1/2) activity at 2 h after injury was also down-regulated. Interestingly, intimal cell replication was significantly blocked when TRAF6 DN was transfected at 7 days after injury. CONCLUSION: TRAF6 plays important roles in cell replication and migration, besides promotion of inflammatory cell infiltration and suppression of apoptosis.

Animals↗
PubMed2004

Conduction performance of collateral vessels induced by vascular endothelial growth factor or basic fibroblast growth factor.

OBJECTIVE: In the present study, we delivered vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) gene to a rabbit model of hind limb ischemia utilizing an ex vivo method of gene transfer, and evaluated the functional performance of the developed collateral vessels. METHOD: The left femoral artery of a male Japanese White rabbit was excised to induce limb ischemia, and a section of skin was resected for culture of auto-fibroblasts. Twenty days later, the VEGF gene, bFGF gene or beta-galactosidase gene (LacZ) was adenovirally transferred to the cultured auto-fibroblasts (5x10(6) cells), and the next day, a pair of specifically infected fibroblasts (total 1x10(7) cells) was injected via the left internal iliac artery of the same rabbit. Pairs of transferred genes into the fibroblasts were as follows: LacZ/LacZ (control group), VEGF/LacZ (VEGF group), bFGF/LacZ (FGF group) and VEGF/bFGF (combination group). Twenty-eight days after cell administration, collateral development and its function were evaluated. RESULTS: Calf blood pressure ratio, resting blood flow of the left iliac artery and capillary density of ischemic muscle showed similar degrees of angiogenic effects in the VEGF and FGF groups, which were significantly greater than those in the control group. On the contrary, angiographic score, collateral conductance and smooth muscle cell (SMC)-positive vessel density in the FGF group were significantly greater than those in the VEGF group. In the combination group, collateral conductance showed synergistic effects, and in vivo blood flow and smooth muscle cell-positive vessel density revealed additive effects of VEGF and bFGF. CONCLUSION: These findings suggested that bFGF-induced collateral development exceeded VEGF-induced collateral development in the induction of arteriogenesis, and that combined gene delivery of VEGF and bFGF produced additive or synergistic effects of collateral development as compared with the effects induced by transfer of each gene alone.

Adenoviridae↗
PubMed2004

In vivo electroporation enhances plasmid-based gene transfer of basic fibroblast growth factor for the treatment of ischemic limb.

BACKGROUND: Angiogenic therapy for ischemic tissues using angiogenic growth factors has been reported on an experimental and a clinical level. Electroporation enhances the efficiency of plasmid-based gene transfer in a variety of tissues. The purpose of this study was to evaluate the angiogenic effects of plasmid-based gene transfer using basic fibroblast growth factor (bFGF) in combination with electroporation. MATERIALS AND METHODS: The transfection efficiency of in vivo electroporation in rabbit skeletal muscles was evaluated using pCAccluc+ encoding luciferase. To evaluate the angiogenic effects of bFGF gene in ischemic limb, we constructed a plasmid, pCAcchbFGFcs23, containing human bFGF cDNA fused with the secretory signal sequence of interleukin (IL)-2. Then, 500 microg of pCAcchbFGFcs23 or pCAZ3 (control plasmid) was injected into the ischemic thigh muscles in a rabbit model of hind limb ischemia with in vivo electroporation (bFGF-E(+) group and LacZ-E(+) group). Other sets of animals were injected with pCAcchbFGFcs23 (bFGF-E(-) group) or pCAZ3 (LacZ-E(-) group) without electroporation. Then 28 days later, calf blood pressure ratio, angiographic score, in vivo blood flow, and capillary density in the ischemic limb were measured. RESULTS: Gene transfer efficiency increased markedly with the increase in voltage up to 100 V. Regarding angiogenic responses, calf blood pressure ratio, in vivo blood flow, and capillary density only in the bFGF-E(+) group were significantly higher than those in LacZ-E(-) group. Angiographic scores in the bFGF-E(+) and bFGF-E(-) groups were significantly higher than that in the LacZ-E(-) group. CONCLUSION: These data suggest that in vivo electroporation enhances bFGF gene transfer for the treatment of ischemic limb muscles.

Animals↗
PubMed2004

Ischemic preconditioning improves oxygenation of exercising muscle in vivo.

BACKGROUND: Ischemic preconditioning (IP) improves tissue tolerance to prolonged ischemia. In this study, we investigated the functional effect of IP on skeletal muscle of rat hind limb by means of near-infrared spectroscopy (NIRS) and by measuring myeloperoxidase (MPO) activity. MATERIALS AND METHODS: Adult male Sprague Dawley rats were divided into four separate protocol groups according to different preparations prior to 2 h of global ischemia: a group of ischemic reperfusion without any preparation (I/R), ischemic reperfusion with ischemic preconditioning (IP+IR), ischemic reperfusion with adenosine infusion (ADO+I/R), and sham operation. Ischemia and ischemic preconditioning were induced by clamping infrarenal abdominal aorta and left common iliac artery. For each rat, an exercise test of gastrocnemius muscles was performed by stimulating sciatic nerve before and after global ischemia while performing NIRS. MPO activity of ischemic muscles was also measured. RESULTS: Half-resaturation time after exercise and MPO activity were significantly improved in IP+IR and ADO+I/R groups. Difference of oxyhemoglobin during exercise was also improved in the IP+IR group. CONCLUSION: This study has demonstrated that IP provides the protective effect on in vivo skeletal muscle oxygenation during exercise.

Animals↗
PubMed2004

Appropriate control of ex vivo gene therapy delivering basic fibroblast growth factor promotes successful and safe development of collateral vessels in rabbit model of hind limb ischemia.

PURPOSE: In our previous study, adenovirus-mediated ex vivo gene transfer of basic fibroblast growth factor promoted significant collateral vessel development in a rabbit model of hind limb ischemia. The present study examined how to control the efficacy and safety of this gene therapy, and also evaluated the feasibility of repeat application of this procedure. METHODS: Modified hFGF gene with the secretory signal sequence was adenovirally transferred to cultured autologous fibroblasts, and various numbers of the cells (2 x 10(5), 1 x 10(6), 5 x 10(6), or 2.5 x 10(7)) or vehicle was injected through the left internal iliac artery in rabbits in whom the left femoral artery had been excised 21 days previously. Twenty-eight days after cell administration, calf blood pressure ratio, angiographic score, blood flow in the internal iliac artery, and capillary density of muscle tissue were measured to analyze collateral vessel development and tissue perfusion in the ischemic limb. To assess delivery efficiency and viral contamination, the distribution of injected cells and the time course of blood anti-adenovirus antibody titer were examined in rabbits treated with various numbers of gene-transduced cells. In addition, animals received two injections, 21 days apart, of fibroblasts infected with adenovirus vector containing the luciferase gene, and luciferase expression was measured to evaluate whether the present therapy is repeatable. RESULTS: At 28 days after cell administration, significant collateral vessel development without detectable side effects was observed in rabbits who received 5 x 10(6) or 2.5 x 10(7) cells, compared with those who received vehicle, and no significant development was detected in animals with fewer than 5 x 10(6) cells (P <.01 for calf blood pressure ratio and capillary density, P <.05 for angiographic score and maximum blood flow). There was no difference in collateral augmentation between rabbits with 5 x 10(6) and 2.5 x 10(7) cells. However, in animals with 2.5 x 10(7) cells a large number of injected cells accumulated in the lungs, anti-adenovirus antibody titer increased significantly, and calf blood pressure in the left hind limb of two rabbits decreased immediately after injection. Luciferase analysis showed very low gene expression after repeated administration. CONCLUSION: These findings suggest that 5 x 10(6) is a suitable number of cells to induce appropriate collateral vessel development and minimize potential side effects of this procedure. Despite use of ex vivo gene transfer, repeat administration of the cells was not feasible. Clinical relevance Since the present study determined the appropriate conditions for effective and safe stimulation of collateral vessels, the clinical relevance of the ex vivo therapy might be carried forward. However, the findings raised another issue that should be resolved before clinical application; that is, the number of gene-transduced cells able to be injected was strictly limited. To estimate the therapeutic range of cell number in humans, additional experiments using large animals are desirable.

Adenoviridae↗
PubMed2004

Aortic wall cell proliferation via basic fibroblast growth factor gene transfer limits progression of experimental abdominal aortic aneurysm.

OBJECTIVE: Our previous study demonstrated that high flow conditions stimulated cell proliferation in the aortic wall in a rat model of abdominal aortic aneurysm (AAA), and we speculated that there is a possible relation between medial cell density and aortic wall integrity. In the present study we delivered the basic fibroblast growth factor (bFGF) gene to the aortic wall of a rat AAA model and evaluated the effects of growth factor-enhanced smooth muscle cell (SMC) proliferation on aneurysm progression. METHODS: AAA was induced in rats by means of infusion of porcine pancreatic elastase. Immediately after elastase infusion the abdominal aorta was filled with an expression plasmid vector containing the bFGF gene (bFGF group) or LacZ gene (control group); then gene transfer to the aortic wall was carried out with an in vivo electroporation method. The animals were killed 7 days after treatment, and the aneurysm was measured. The numbers of SMCs, macrophages, and endothelial cells were counted with immunostaining, and cell replication was evaluated with bromodeoxyuridine (BrdU) staining. RESULTS: Aneurysm diameter in the bFGF group was significantly smaller than that in the control group (4.6 +/- 0.3 mm vs 6.5 +/- 1.4 mm; P <.01). The numbers of medial SMCs and BrdU-incorporated cells in the bFGF group were significantly greater than those in the control group (SMC, 101 +/- 34 per high-power field [hpf] vs 80 +/- 31/hpf; P <.05, BrdU, 107 +/- 63/hpf vs 50 +/- 33/hpf; P <.05), whereas no difference was detected in the numbers of macrophages and endothelial cells between the 2 groups. CONCLUSIONS: Delivery of bFGF to the aortic wall induced significant enhancement of medial SMC proliferation, without an increase in inflammatory infiltration, then successfully limited aneurysm enlargement. These findings suggest that increased medial cellularity inhibits aneurysm formation, which possibly offers a clue for developing a new strategy for treatment of AAAs.

Animals↗