An investigation into the role of inflammatory cells in Dupuytren's disease

An immunohistochemical study was performed on nodules excised from the palmar fascia of patients with Dupuytren's contracture. In cellular nodules, antibodies to actin (used as a marker for myofibroblasts), desmin, vimentin, Mac 387 (a macrophage marker) and leucocyte common antigen were used. A correlation was demonstrated between the numbers of macrophages and the presence of myofibroblasts. The presence of myofibroblasts is generally considered to indicate the active stage of the disease. Inflammatory cells other than macrophages were largely absent from the nodules, although lymphocytes were frequent in the tissue around the nodules. Microvascular changes were prominent in the nodules and pericyte proliferation was observed around occluded capillaries. Release of growth factors from macrophages may be important in Dupuytren's contracture, as is the case in other fibrotic diseases. The possible role of macrophages in the aetiology of Dupuytren's disease is discussed.     

Study on intraluminal embolization with microcoils treating traumatic pseudoaneurysms in common carotid artery in rabbits

Objective: To evaluate the long-term effect of endovascular occlusion with microcoils on traumatic pseudoaneurysms (TPAs) in the common carotid artery in rabbits. Methods: TPAs in the right common carotid artery were surgically made in 16 rabbits. At 3-4 weeks after operation, the survived 12 models were randomly divided into a control group (n = 3) with no treatment and an experimental group (n = 9 ), in which TPAs were intraluminally embolized with microcoils and corresponding therapy was given. Three months after embolization, the TPAs were examined with digital subtraction angiography and pathology. Results : The 3 rabbits in the control group all died of rupture of TPA. Among the 9 TPAs occluded with microcoils, 4 were completely occluded, 4 were partially occluded, and 1 was excluded due to the microcoils migrating into the parent artery. Three months after embolization, the 4 TPAs which were completely occluded remained obliterated as determined by digital subtraction angiographic findings. The parent artery remained unobstructed and the structure of the TPAs were replaced by a mass of scar tissues. The 4 TPAs which were partially occluded remained unruptured and the microcoils were compressed. Conclusions: The lumen in TPA can be completely occluded by microcoils and the parent artery is unblocked. Partial occlusion of the lumen ‘can also prevent the rupture of TPA.     

Laser angioplasty: an atherosclerotic swine model

Rapid production of occlusive, atherosclerotic iliac artery lesions was achieved in 25 of 27 (93%) Yucatan miniature swine, using a combination of high cholesterol diet and mechanical endothelial denudation. Animals were fed a diet with 2% of their calories as raw cholesterol 2 weeks prior to balloon denudation of iliac arteries, which resulted in atherosclerotic lesions within 8 weeks. Early after denudation we have demonstrated total occlusion of arteries by fibrin thrombi, which in time organize and ultimately result in fibrotic occlusive disease. The arterial walls and intima show varying degrees of foam cell infiltration with destruction of the internal elastic lamina and calcification. Totally occluded lesions show fibrointimal proliferation, fibrosis, and multiluminal channels, which are probably secondary to organized thrombus. Our model of occlusive iliac artery disease involving vessels of 1 to 3 mm in diameter allows the development of catheter systems suitable for use in human peripheral and coronary arteries. This model is useful for the study of angioplasty, whether mechanical, balloon, or laser-mediated.     

Flow in coronary artery bypass grafts to totally and partially occluded left anterior descending coronary arteries

Flow was determined by electromagnetic flowmeter in vein bypass grafts in 20 patients with a totally occluded left anterior descending (LAD) coronary artery and on 61 patients with a partially occluded LAD. The median flow in LAD grafts was 14.5 ml/min with total LAD occlusion, and 40 ml/min with partial LAD occlusion (p less than 0.001). In cases of total LAD occlusion, the presence of mild or moderate anteroseptal wall dysfunction was associated with more satisfactory flow than was the case with severe anteroseptal wall dysfunction (p less than 0.02). Flows over 25 ml/min were found only when the LAD distal to total occlusion was 1.5 mm or greater. Unsatisfactory flows were consistently found with total LAD occlusion, poor ventricular function, and a distal LAD less than 1.5 mm. Repeat catheterizations to determine an unsatisfactory patency rate under these conditions would be necessary to alter our policy of grafting all suitable vessels beyond a total occlusion.     

Noninvasive assessment of microvessels with the duplex scanner

This study was undertaken to determine if a duplex scanner equipped with a new 10 MHz probe could accurately evaluate microvascular anastomotic patency. The overall predictive accuracy of the duplex scanner was 90% (p less than 0.0001) with no difference noted among the three main anastomotic groups examined--acute artery, acute vein, and long-term artery. There was, however, a statistically significant difference (p less than 0.05) in the ability to interpret vessels that were patent (100%) versus those that were partially occluded (73%) or occluded (88%). It is believed that the duplex scanner has potential applications to preoperatively and intraoperatively study microvessels and postoperatively to supplement other techniques in monitoring acute and long-term anastomotic patency.     

Secondary ischaemia in experimental free flaps--treatment by long acting prostacyclin analogues.

Secondary postoperative ischaemia due to venous occlusion is the most detrimental insult to free microvascular flaps. In an experimental rat free flap model the efficacy of long acting prostacyclin analogues iloprost (Ilomedin) and cicaprost in venous occlusion induced postoperative ischaemia was studied. Free, microvascular groin flaps were transplanted to the neck and the draining veins were temporarily occluded on the first postoperative day for a total of 20 min. In the untreated control group, haemorrhagic flap necrosis occurred. Intravital microscopy after secondary ischaemia revealed flap areas without reperfusion. The functional vessel density was significantly reduced. Reperfused capillaries were tortuous and significantly dilated. After reperfusion the interstitial leakage of macromolecular dextran increased, indicating loss of microvascular endothelial integrity. Intraarterial and intravenous applications of iloprost were able to diminish the ischaemic effects, giving a flap survival rate of 83%. Similar results were obtained by intravenous and enteral administration of cicaprost. Transcutaneous oxygen partial pressure measurements confirmed the viability of the surviving flaps. We conclude that both iloprost and cicaprost are effective in preventing venous occlusion induced failure of free microvascular groin flaps.     

脉冲染料激光治疗充血性瘢痕的研究与应用

目的：研究585nm的闪光灯泵浦脉冲染料激光(PDL)对充血性瘢痕的影响。方法：对治疗前、后的瘢痕行常规病理、胶原纤维VG染色及免抗人8因子多抗行微血管染色以观察PDL对胶原及瘢痕内微循环的影响。同时行临床观察及记录。结果：PDL治疗后瘢痕内毛细血管减少，瘢痕内胶原沉积下降，临床症状明显改善。结论：①585nm PDL激光通过破坏瘢痕内微血管，使胶原降解增多，合成减少。从而有效改善充血性瘢痕的症状、高度、皮肤纹理、颜色等。②其对瘢痕形成的病理过程进行了有效干预，因此，也可以用于预防伤后瘢痕增生。③临床治疗需3次左右，每次间隔应为4-6周。     

Immunohistochemical study of collagen types in human foetal lung and fibrotic lung disease.

Highly purified type-specific anti-collagen antibodies (prepared in animals to types I, II, III, and IV bovine collagen) were used in an indirect immunofluorescence method for the study of human lung collagen. The tissue localisation of each collagen type, and the apparent type I:III collagen ratio was assessed in normal foetal and adult lung and in fibrotic lung lesions. In the latter, the relationship of the findings to the natural history of the lesion was considered. This method was compared with routine connective tissue stains. The following observations were made. (1) Foetal lung in the canalicular phase of development proved a useful substrate for validating and standardizing the procedure. (2) Collagen fluorescence was more sensitive than connective tissue stains in detecting collagen in foetal tissues and sites of early fibrosis. (3) On the basis of collagen-type fluorescence, two distinctive patterns of fibrosis were recognised. Areas of mature collagen surrounding vessels and bronchi and in established scar tissue, for example in asbestotic pleural plaques, were virtually exclusively type I collagen. By contrast, areas of early active fibrosis like sarcoid nodules and organising pneumonia, which usually contained variable numbers of fibroblasts and chronic inflammatory cells, were characterised by an increased proportion of type III collagen and a greater intensity of both types I and III collagen fluorescence. The possible significance of this change in type III:I collagen ratio is discussed. Determination of the stage of fibrotic lesions by this method might have applications in the prediction of disease progression, and influence management of some conditions.     

The effect of pulsed holmium-YAG laser on in vitro and in vivo atherosclerotic plaque

Laser application for atherosclerotic ablation is still limited. The pulsed Holmium-YAG (HO-YAG) laser has physical characteristics which may improve vascular recanalization. We therefore examined the effect of this laser on cadaver human atherosclerotic aortae, human amputated legs and atherosclerotic rabbits in vivo. The pulsed HO-YAG laser successfully ablated calcific and fibrotic aortic segments. Totally occluded arteries in amputated legs including calcified atherosclerotic lesions were successfully recanalized using 165–350 pulses of 0.35–0.4 J energy per pulse transmitted through commercially available fibre optics. Percutaneous delivery of laser energy to the descending aorta of atherosclerotic rabbits was not traumatic to the arterial wall. These results demonstrate the advantages of the pulsed HO-YAG laser to ablate fibrotic and calcific atheroma and to safely recanalize occluded arteries.     

Morphological studies of cellular responses to experimental arterial grafts

Cross-carotid microvascular bypass grafts 2-3 mm in diameter were implanted using microsurgical techniques for end-to-end anastomosis in four dogs. One autograft control and one of three denatured human umbilical artery xenografts (HUAG) were patent at 5 weeks. One of the other two denatured HUAGs had thrombosed at 1 week, and the other was occluded at 5 weeks. Host and graft vessel specimens were evaluated histologically as well as with transmission electron microscopy after sacrifice. Results indicate that failure of reconstitution of a true endothelial layer, presence of a subintimal myofibroblast population, increased collagen deposition of the muscularis, and occlusion of the adventitial and mural microcirculation were observed in both the early and late nonpatent vessels but not in the patent specimens. Evidence for myointimal cell proliferation was present in both patent and occluded grafts. A cohesive intimal layer was observed in both patent cases. Microvascular occlusion, due to an excess of endothelial cells, of new vasa vasorum in one case seems related to increased fibrosis, which could have resulted in graft stenosis. The surgical procedures and subsequent morphological analyses were adequate and sufficient for use in a long-term study of the possible causes of graft failure.     

Multiple necrotic nodules of the liver simulating liver metastasis

A 70-year-old man was referred to our hospital due to anemia and elevated serum tumor marker levels. He had advanced colon cancer, and hepatic lesions were found incidentally. On ultrasonography (US) and computed tomography (CT), the hepatic lesions had a maximum diameter of 20 mm and were located in Couinaud's segments V, VI, VII, and VIII, which suggested liver metastasis. On early- and late-phase CT during hepatic arteriography (CTHA), all of the lesions had rim enhancement. On early-phase CT during arterioportography (CTAP), all of the lesions were seen as nodules with an irregular perfusion defect, and on late-phase CTAP, all the lesions gradually became iso-dense, and their shape and size changed. Based on the CTAP findings, these lesions were thought to be fibrotic tumors. Partial resection of the liver (including the lesions in Couinaud's segments V and VIII) was done. Histological examination revealed that the lesions were necrotic nodules. Thus, CT angiography (CTHA and CTAP) was useful for identifying necrotic nodules, because their appearance on this modality is different from that of liver metastases.     

脉冲染料激光治疗充血性瘢痕的机理研究

目的 研究585 nm的闪光灯泵浦脉冲染料激光（FLPDL）对充血性瘢痕的影响.方法 对治疗前、治疗后的瘢痕行常规病理、胶原纤维VG染色及兔抗人八因子多抗行微血管染色以观察FLPDL对胶原及瘢痕内微循环的影响.同时行临床观察及记录.结果 PDL治疗后瘢痕内毛细血管减少,瘢痕内胶原沉积下降,临床症状明显改善.结论 ①585 nm FLPDL激光通过破坏瘢痕内微血管,使胶原降解增多,合成减少.从而有效改善充血性瘢痕的症状、高度、皮肤纹理、颜色等.②其对瘢痕形成的病理过程进行了有效干预,因此,也可以用于预防伤后瘢痕增生.③临床治疗需3次左右,每次间隔应为4～6周.     

Comparative study on microvascular occlusion and apoptosis in body and limb wounds in the horse

Wound repair in horse limbs is often complicated by exuberant granulation tissue, a condition characterized by excessive fibroplasia and scarring and that resembles hypertrophic scars and keloids in man. The aim of this study was to compare microvascular occlusion and apoptosis in wounds of the limb with those of the body, which heal normally. Five 6.25 cm(2) wounds were created on both forelimbs and on the body of six horses. One limb was bandaged to stimulate excessive fibroplasia. Weekly biopsies were evaluated histologically and immunohistochemically for mutant p53 protein by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling to localize and quantify apoptosis, and by electron microscopy to measure microvessel luminal diameters. Histologic examination revealed protracted inflammation as well as slowed epithelialization and deficient fibroblast orientation in limb wounds, particularly those with excessive fibroplasia. Microvessels were occluded significantly more often in limb wounds, and the balance of apoptotic signals was altered against apoptosis in the former, although this could not be confirmed quantitatively. Data suggest that microvascular occlusion and a dysregulated apoptotic process may be involved in the excessive accumulation of extracellular matrix within limb wounds. This might provide a basis for the development of targeted therapies to prevent and treat excessive fibroplasia and extensive scarring in horses.     

Sequential and spatial profiles of apoptosis in ischemic penumbra after two-vein occlusion in rats

OBJECT: The two-vein occlusion model is known to be useful for ischemic penumbra studies in vivo. It was applied here to examine sequential changes in the expression of Bax and Bcl-2 proteins and in apoptotic cells to assess the relationship between penumbra and apoptosis. METHODS: Two cortical veins were occluded photochemically by using rose bengal dye in 27 Wistar rats. The animals were killed with perfusion fixation at the following intervals: 4, 12, 24, 48, 96, and 168 hours after vein occlusion (four at each interval; three additional rats were sham-treated). Immunohistochemical analysis for the Bcl-2 family of proteins was performed along with the terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay to examine the relationship to single-cell death. Cells positive for antiapoptotic proteins began to appear in the TUNEL assay for animals killed 24 hours after vein occlusion, with a peak at 48 hours. These cells were localized in the core of infarction. Immunohistochemical staining for Bax protein showed an increased presence around ischemic lesions at 4 hours after vein occlusion, and the amounts continued to rise until 24 hours, when the localization was diffuse around the core of infarction. Negative findings on immunohistochemical studies for Bcl-2 protein were seen at the early phase after two-vein occlusion. CONCLUSIONS: After vein occlusion, apoptosis appeared sequentially and widely in cortical lesions considered to be the penumbra. Therefore, control of apoptosis would be expected to offer a therapeutic window for treatment of venous infarction.     

Diabetes downregulates GLUT1 expression in the retina and its microvessels but not in the cerebral cortex or its microvessels

Capillaries in the retina are more susceptible to develop microvascular lesions in diabetes than capillaries in the embryologically similar cerebral cortex. Because available evidence implicates hyperglycemia in the pathogenesis of diabetic retinopathy, differences in glucose transport into the retina and brain might contribute to this observed tissue difference in susceptibility to diabetes-induced microvascular disease. Thus, we compared levels of GLUT1 and GLUT3 expression in the retina, cerebrum, and their respective microvessels by Western blot analysis. In nondiabetic animals, the content of GLUT1 protein in retina and its microvessels was multifold greater than that of cerebral cortex gray matter and its microvessels. Streptozotocin-induced diabetes of a 2-week or 2-month duration reduced GLUT1 expression in the retina and its microvasculature by approximately 50%, but it resulted in no reduction in GLUT1 expression in cerebrum or its microvessels. The density of capillaries in retinas of diabetic animals did not change from normal, and so the observed decrease in GLUT1 expression in the retina and retinal capillaries of diabetic animals cannot be attributed to fewer vessels. Despite the diabetes-induced reduction of GLUT1 expression in retina, neural retina of diabetic rats still possessed more GLUT1 than the cerebrum. Retinal pigment epithelium (RPE) possessed more GLUT1 than neural retina or its microvessels, and expression of the transporter in the RPE was not affected by diabetes. GLUT3 levels were greater in cerebral gray matter than in retina, and they were unaffected by diabetes in either tissue. The effect of diabetes on GLUT1 expression differs between retina and cerebral cortex, suggesting that glucose transport is regulated differently in these embryologically similar tissues. Because diabetes results in downregulation of GLUT1 expression in retinal microvessels, but not in RPE, the fraction of the glucose entering the retina in diabetes is likely to be greater across the RPE than across the retinal vasculature.     

Implants of hypertrophic scars and keloids into the nude (athymic) mouse: viability and morphology

Pieces of hypertrophic scars and keloids were implanted into subcutaneous pockets of nude (athymic) mice and carried for varying times up to 246 days. No rejection phenomena were observed. Microvascular anastomosis occurred between host and implant within the first several days. Remodeling of the edges of the implant occurred very early. Multiple regression analysis of volume measurements suggests there was a size reduction of the implants with time. Yet virtually all implants retained their original histotypic character regardless of the length of implantation. The nodular character typical of all hypertrophic scars and keloids was retained in every case. Histologic analysis, confirmed by transmission electron microscopy, demonstrated a sustained cellular character. The degree and magnitude of microvascular occlusion was also sustained. Use of the nude mouse for implants of hypertrophic scar or keloid sustains true viability and morphology of the lesions. This procedure shows clear potential as an experimental model for the study of these lesions.     

Are keloid and hypertrophic scar different forms of the same disorder? A fibroproliferative skin disorder hypothesis based on keloid findings

Hypertrophic scars (HSs) and keloids are commonly seen as two different diseases by both clinicians and pathologists. However, as supported by histological evidence showing they share increased numbers of fibroblasts and accumulate collagen products, HS and keloid might be different forms of the same pathological entity, rather than separate conditions. To test this hypothesis, keloids from patients who underwent scar excisions (n = 20) in Nippon Medical School from 2005 to 2010 were examined histologically. The proportion and distribution of cellular and matrix collagen components were evaluated at the centre and periphery of each sample. In keloid samples, coexistence of hyalinised collagen, which is the most important pathognomonic characteristic of a keloid and dermal nodules that are considered to be characteristic of HS, was found. Moreover, hyalinised fibres appeared to initiate from the corner of the dermal nodules. Key features of inflammation such as microvessels, fibroblasts and inflammatory cells all decreased gradually from the periphery to the centre of keloids, indicative of reduced inflammation in the centre. Thus, we hypothesise that HS and keloid can be considered as successive stages of the same fibroproliferative skin disorder, with differing degrees of inflammation that might be affected by genetic predisposition.     

Iatrogenic damage to the pediatric airway Mechanisms and scar development

Iatrogenic damage to the pediatric airway occurs rather often. Most injuries will heal without any sequelae because larynx and trachea of children tolerate considerable trauma. However, sometimes the injury is penetrating the mucosa and scar formation can lead to an obstruction of the airway which is followed by a tracheostomy and long term surgery. A great problem is the early detection of trauma since noisy breathing develops often late when scar formation has occluded more than 50% of the airway. A selection of photo documents of airway endoscopy out of more than 5000 photos from the years 1987–2007 were used to explain the development of injuries from minor lesions to large areas of necrosis of the mucosa of larynx and trachea of infants and children. The visualization of airway lesions might help to prevent iatrogenic damage.     

Myocardial contractile force as influenced by direct coronary surgery

Myocardial contractile force (MCF) measured by direct application of a strain-gauge arch to the left ventricular surface was determined intraoperatively in 11 patients having saphenous vein graft (SVG) bypass of acute or chronic coronary arterial obstruction. The MCF determinations with the grafts open (control), occluded, and released demonstrated a consistent reduction (average 31%) in contractility during graft occlusion and a prompt return to control levels following graft release without alteration in other aspects of ventricular function. Similar changes were not observed during graft occlusion if the arch was applied to nonviable (scarred) myocardium or to areas outside the region of graft perfusion. The SVG augmentation of blood flow to acute or chronically ischemic but viable myocardium enhances MCF or isometric systolic tension, from which coincident improvement in ventricular function should be anticipated.     

The Effect of Acute Coronary Artery Occlusion during Cardioplegic Arrest and Reperfusion on Myocardial Preservation

A study was undertaken to evaluate the effect of acute occlusion of a coronary artery during cardioplegic arrest on myocardial preservation and to elucidate the influence of reestablishment of flow versus continued occlusion during the phase of myocardial reperfusion. Coronary occlusion was simulated, and myocardial viability was determined by measuring tissue levels of adenosine triphosphate (ATP) and creatine phosphate (CP) in biopsies of the posterior left ventricular wall. Eighteen pigs were divided into three equal groups consisting of animals with (1) patent right coronary arteries during arrest and reperfusion, (2) occluded right coronary arteries during arrest and patent during reperfusion, and (3) occluded right coronary arteries during arrest and reperfusion.The results of ATP and CP measurements showed that while poorer protection was afforded during two-hour arrest when the coronary artery was occluded, the risk of damage was much greater during reperfusion. Failure to restore adequate blood flow by retention of occlusion caused a concurrent decrease in ATP and CP levels below prescribed limits of myocardial tolerance. When occlusion occurs in the clinical setting, impeding cardioplegia and reperfusion, the importance of revascularization is emphasized.