Chronic Lesions (chronic + lesion)

Distribution by Scientific Domains
Distribution within Medical Sciences


Selected Abstracts


Axonal Pathology and Loss Precede Demyelination and Accompany Chronic Lesions in a Spontaneously Occurring Animal Model of Multiple Sclerosis

BRAIN PATHOLOGY, Issue 3 2010
Frauke Seehusen
Abstract Axonal damage has been highlighted recently as a cause of neurological disability in various demyelinating diseases, including multiple sclerosis, either as a primary pathological change or secondary due to myelin loss. To characterize and quantify axonal damage and loss in canine distemper demyelinating leukoencephalomyelitis (DL), formalin-fixed paraffin-embedded cerebella were investigated histochemically and immunohistochemically using the modified Bielschowsky's silver stain as well as antibodies against nonphosphorylated (n-NF), phosphorylated neurofilament (p-NF) and ,-amyloid precursor protein (,-APP). Injured axons characterized by immunoreactivity against n-NF and ,-APP were detected in early distemper lesions without demyelination. In subacute and chronic demyelinating lesions the number of injured axons increased. Moreover, a significant decrease in axonal density was observed within lesions and in the normal appearing white matter in DL as determined by morphometric analyses using Bielschowsky's silver stain and p-NF immunohistochemistry. Summarized, the observed findings indicate that axonal damage (i) occurs early in DL; (ii) can be detected before myelin loss; and (iii) represents a pivotal feature in advanced lesions. It must be postulated that axonal damage plays an important role in the initial phase as a primary event and during progression of nervous distemper as a result of demyelination. [source]


Mid-term effects of steroid therapy on childhood-onset IgA nephropathy

NEPHROLOGY, Issue 2001
S Watanabe
Purpose: IgA nephropathy (IgAN) is considered the most common glomerular disease in the world. Although treatment of children with severe IgAN with predonisolone (PSL) has been reported, the mid-term prognosis of paediatric patients treated with PSL is unclear. In the present study we examined the mid-term effects of PSL therapy. Method: Thirty-seven paediatric patients with IgAN (18 males, 19 females), whose biopsy findings showed acute segmental lesions including cellular crescent and adhesion in more than 10% of glomeruli examined, were prospectively treated with PSL plus heparin-warfarin and dipyridamole (Tx) for 1.5 years and followed up over 1 years after Tx end. Fifteen age and histological grade-matched children with IgAN (six males, nine females), who had never been treated with PSL, were also evaluated as a historical control. The mean observation period was 5.0 ± 1.8 years (range, 2.5,8.6 years). The histological grade (acute lesion) and stage (chronic lesion) were scored semiquantitatively based on the Shigematsu's grade-stage system.1 Result: Proteinuria decreased 1.48 g/day/1.73 m2 at the start of Tx to 0.32 g/day/1.73 m2 at the end of Tx. Eighteen patients (48.6%) achieved complete remission (CR). No patient developed chronic renal failure in Tx group, while two of the controls deteriorated renal function in the last observation. The pattern of responsiveness to Tx were divided into three groups according to the levels of proteinuria: CR, rebound (> 0.5 g/day/1.73 m2) and incomplete remission (< 0.5 g/day/1.73 m2). The rebound of proteinuria is usually accompanied with PSL reduction. The grade of glomerular pathology was improved with Tx (Gg: 0.8,0.3), while the stage of tubulo-interstitial change progressed (Sint: 0.7,1.2). Conclusions: The present study shows that Tx to children with IgAN showing acute lesions for 1.5 years is effective to subside acute glomerular injury. However, because clinical courses of treated patients vary in each patient, dosage and duration of PSL administration should be modified in their clinical setting. [source]


Surgical Treatment of Chronic Gluteal Hidradenitis Suppurativa: Reused Skin Graft Technique

DERMATOLOGIC SURGERY, Issue 2 2003
Hung-wen Kuo MD
BACKGROUND The treatment of chronic lesions in hidradenitis suppurativa (HS) remains a challenge for dermatologists. In most cases, wide surgical excision of the affected skin reduces the recurrence rate to a minimum. Split-thickness skin grafts have usually been applied to resurface large postoperative defects. OBJECTIVE The aim of this study is to introduce an alternative method of skin grafting, called "reused" or "recycled" skin graft, for the reconstruction of the large skin defect with chronic gluteal HS. METHODS The study consisted of six patients (two females and four males) with gluteal HS. After a wide en bloc excision, the wound was immediately recovered with meshed-skin graft, made from the resected skin itself. Thus, the sacrifice of the skin donor is spared. The drum dermatome (Padgett-Hood) is suitable to take the split-skin graft from the resected skin of the affected buttock. The thickness of grafts was set between 12/1,000 and 20/1,000 inches, and all grafts were meshed with 1.5 times the expansion. The skin grafts were secured in place on the wound and a tie-over dressing was applied. RESULTS Postoperative complications were usually minor ones, such as hematoma, discharge, and small areas of graft skin necrosis (less than 1 cm2), although one patient developed a 3×4 cm2 graft necrosis and wound infection. The follow-up period after surgery ranged from 8 to 36 months. No patient experienced any functional disabilities or recurrence during follow-up years. CONCLUSION When the epidermal involvement remains mild to moderate, this reused skin graft technique is an alternative choice to resurface the surgical defect of gluteal HS. It is superior to the conventional procedure, which requires fresh skin donor site. [source]


Long-term evolution of the acute tubular necrosis (ATN) induced by glycerol: role of myofibroblasts and macrophages

INTERNATIONAL JOURNAL OF EXPERIMENTAL PATHOLOGY, Issue 4 2002
Telma J. Soares
Summary. Late structural changes such as interstitial fibrosis in the renal cortex and tubular atrophy have been detected after severe acute tubular necrosis (ATN). The aim of this study was to investigate the expression of fibronectin, ,-smooth muscle actin and macrophages during the evolution of the ATN induced by glycerol and their relationship with the late structural changes observed in the kidneys of these animals. Forty-nine male Wistar rats were injected with a 50% glycerol solution, 8 mL/kg (4 mL/kg applied i.m. to each hind leg) and 14 with 0.15 m NaCl solution. Before glycerol injection on day 1, water was removed for 17 h. Blood and urine samples were collected 1 day after the injection to quantify sodium and creatinine. The animals were killed 5, 30 and 60 days after the injections and the kidneys removed for histological and immunohistochemical studies. The results of the histological and immunohistochemical studies were scored according to the extent of lesion or staining in the cortical tubulointerstitium, respectively. The percentage of tubulointerstitial lesions was determined by morphometry. Glycerol-injected rats presented a transitory increase in plasma creatinine levels and in fractional sodium excretion. The immunohistochemical studies showed increased fibronectin, ,-smooth muscle actin (,-SM-actin), TGF-, and ED-1 (macrophages) staining in the renal cortex from rats killed 5, 30 and 60 days after glycerol injection (P < 0.05) compared to control. The animals killed on day 30 and 60 also presented chronic lesions (fibrosis, tubular dilatation and atrophy) in the renal cortex, despite the recovery of renal function. Macrophages, TGF-, and myofibroblasts may have contributed to the development of renal fibrosis in these rats. [source]


The use of topical calcineurin inhibitors in lupus erythematosus: an overview

JOURNAL OF THE EUROPEAN ACADEMY OF DERMATOLOGY & VENEREOLOGY, Issue 1 2008
U Wollina
Abstract Lupus erythematosus (LE) shows a broad range of cutaneous symptoms, including acute, subacute and chronic lesions. The gold standard of established topical treatment consists of medium- to high-potency corticosteroids. Because face and neck are often involved, adverse effects of prolonged corticosteroid use are not uncommon. There is a need of steroid-free topical treatment in LE. With the development of topical calcineurin inhibitors, tacrolimus and pimecrolimus, there is an alternative available. The present study reviews the literature data on topical tacrolimus and pimecrolimus for malar rash, subacute lesions and discoid chronic lesions among others. The present data argue for an efficacy of these compounds in acute and subacute cutaneous LE manifestations with a rapid response and only minor side-effects when used as an adjunct to systemic treatment. In chronic discoid LE, hypertrophic plaques do not well respond because of limited penetration. The primary target seems to be the decrease or blocking of cytokine production by activated T lymphocytes. [source]


Abstracts of the 8th Meeting of the Italian Peripheral Nerve Study Group: 79

JOURNAL OF THE PERIPHERAL NERVOUS SYSTEM, Issue 1 2003
U Del Carro
Peripheral neuropathy is one of the most common secondary complications of diabetes mellitus, causing severe and prolonged morbidity. However, clinical and experimental studies have reported that careful glucose control may prevent, stabilize, and/or reverse neuropathy and other chronic diabetic complications. Unfortunately, insulin therapy does not prevent the development or progression of chronic lesions in the vessels, kidneys, eyes, or nerves of the diabetic patient. There is great interest in investigating other forms of endocrine replacement therapy, such as transplantation of the pancreas or of the islets of Langerhans (IT). Diabetic polyneuropathy (DP) evolution is characterized by progressive demyelination and axonal loss and is manifested by signs and symptoms on physical examination and abnormalities in nerve conduction studies (NCS). NCS provide reliable, noninvasive, objective measures of peripheral nerve function and constitute the most important technique for the evaluation of the severity of DP in clinical trials. Several research groups have demonstrated that skin biopsy with measurement of intraepidermal nerve fiber density is another method minimally invasive and repeatable that provides direct pathologic evidence of axonal damage in diabetic neuropathy. Fifty-one consecutive IDDM patients with or without end stage renal disease were enrolled at the moment of islet (Is), kidney (KD), kidney-pancreas (KP) or kidney-islet (KI) transplantation. Patients underwent skin biopsy punch, neurologic examination and neurophysiological investigation. Particularly, 20 pts underwent KP tx, 16 KD tx, 10 islet tx and 5 KI. The patients were comparable for duration of diabetes, dialysis (when present), age, lipid profile. In half of the patients a follow-up of 2 years has been reached. After KP tx, and partially with KI, a complete normalization of glycometabolic control has been achieved, with statistically lower HbA1c in comparison with KD group (KP = 6.2; 0.1% vs. KD = 8.4; 0.5%; p < 0.01). In the KI/Is group, a long-term restoration of islet endocrine function has been achieved, with insulin independence. When this has been lost, a persistent secretion of C-peptide was shown for a long period of time. This was correlated with a global improvement quality of life and vascular structure. Preliminary results will be presented. [source]


Effects of Corticosteroid Therapy on the Long-Term Outcome of Radiofrequency Lesions in the Swine Caval Veins

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 8 2008
GUILHERME FENELON M.D.
Background: We explored the angiographic and pathological effects of corticosteroids on the long-term outcome of radiofrequency (RF) ablation lesions in the swine caval veins. Methods: Under fluoroscopy guidance, a single linear RF lesion (4-mm tip, 60°C, 180 seconds) was created in each vena cava (from ±2 cm into the vein to the venoatrial junction) of 20 anesthetized minipigs (35± 2 kg). Three groups were studied: acute (n = 4), killed 1 hour after RF; control (n = 8), sacrificed 83± 1 days after RF; and pigs (n = 8) receiving hydrocortisone (400 mg i.v. after RF) and prednisone (25 mg po for 30 days), killed 83± 1 days post-RF. Angiography was performed before, immediately after ablation, and at follow-up. Then, animals were sacrificed for histological analysis. Results: Mild (<40%) or moderate (41,70%) acute luminal narrowing occurred in 19/20 (95%) inferior veins and in 13/20 (65%) superior veins. Severe (>70%) stenosis and occlusions were not noted. At follow-up, in both chronic groups, mean vessel diameters returned to baseline and progression of luminal narrowing did not occur in any vein. Of note, superior and inferior vena cava angiographic diameter for control and treated pigs did not differ. The same was observed for the cross-sectional luminal area. Acute lesions displayed transmural coagulative necrosis whereas chronic lesions revealed marked fibrosis. Histological findings were similar in controls and treated pigs. Conclusion: In this model, mild and moderate stenosis, occurring immediately after ablation, seems to resolve over time. Corticosteroids do not affect the long-term outcome of such RF lesions in the caval veins. [source]


Acute and Chronic Effects of Extensive Radiofrequency Lesions in the Canine Caval Veins: Implications for Ablation of Atrial Arrhythmias

PACING AND CLINICAL ELECTROPHYSIOLOGY, Issue 12 2006
GUILHERME FENELON M.D.
Background: Although radiofrequency (RF) ablation within the caval veins has been increasingly used to treat a variety of atrial tachyarrhythmias, the consequences of RF ablation in the caval veins are unknown. We explored the acute and chronic angiographic and pathological effects of extensive RF ablation in the caval veins. Methods: Under fluoroscopy guidance, conventional (4 mm tip, 60°C, 60 seconds) RF applications (n = 6,7) were delivered in each vena cava (from ±2 cm into the vein to the veno-atrial junction) of 15 dogs (10 ± 3 kg). Animals were killed 1 hour and 5 weeks after ablation for histological analysis. Angiography was performed before ablation (acute dogs only) and at sacrifice to assess the degree of vascular stenosis. Results: In acute dogs (n = 5), luminal narrowing was noted in 10/10 (100%) targeted veins (mild in two; moderate in three and severe in five, including two total occlusions). In the six chronic animals that completed the protocol (four died during follow-up), stenosis was also observed in 12/12 (100%) ablated veins (mild in six; moderate in four and severe in two). Of these, one superior vena cava was suboccluded with development of extensive collateral circulation. Histologically, acute lesions displayed typical transmural coagulative necrosis, whereas chronic lesions revealed intimal proliferation, necrotic muscle replaced with collagen, endovascular contraction, and disruption and thickening of the internal elastic lamina. Conclusion: In this model, extensive RF ablation in the caval veins may result in significant vascular stenosis. These findings may have implications for catheter ablation of arrhythmias originating within the caval veins. [source]


Different cytokine production and activation marker profiles in circulating cutaneous-lymphocyte-associated antigen+ T cells from patients with acute or chronic atopic dermatitis

CLINICAL & EXPERIMENTAL ALLERGY, Issue 4 2004
C. Antúnez
Summary Background Atopic dermatitis (AD) is an inflammatory skin disease whose lesions can have two stages: acute and chronic. In skin biopsies a biphasic pattern of cytokine expression has been shown, Th2 in acute lesions and Th1 in chronic AD lesions. Objective We investigated the expression of an activation marker and a homing receptor, as well as cytokine production, in different peripheral blood T cell subpopulations from AD patients with chronic (Group A) and acute lesions (Group B) and controls. Methods We evaluated 26 adult AD patients (12 Group A, 14 Group B) and 14 non-atopic controls. IgE was measured by immunoassay. CD4, CD8, cutaneous-lymphocyte-associated antigen (CLA) and human leucocyte antigen (HLA)-DR expression, and cytokine production (IL-2, IL-13, IFN-,, TNF-,, IL-10, IL-4) were analysed in mononuclear cells by flow cytometry. Results In Group B there was a significant increase in eosinophil levels and a non-significant increase in IgE. In Group A we found an increase in CLA+CD4+ cells (8.19±1.84) compared with controls (4.83±0.53) (P<0.05) and CD4+HLA-DR+ cells in the CLA+ subpopulation (45.54±15.40) compared with controls (30.49±6.07) (P<0.05). In the CLA+CD4+ subpopulation, there was a significant increase in IL-4, IL-13 and TNF-, production in Group B (12.46±7.7, 11.26±5.97, 43.92±15.55) compared with controls (5.34±3.50, 4.54±1.78, 19.29±9.97) with no differences in Group A. Conclusion Greater immunological differences were detected in peripheral blood from patients with acute compared with chronic lesions, especially in the circulating T cell-subset with skin tropism that preferentially responded to cutaneous allergens. This is the first demonstration of phenotypic changes in circulating CLA+ T cells between AD patients with acute and chronic lesions. [source]