[Show abstract][Hide abstract] ABSTRACT: Recent studies have reported a high incidence of postoperative unfavorable cardiac-related events in patients with diabetes who underwent coronary artery bypass grafting (CABG). Structural and functional characteristics of CABG conduits, which have been shown to play an important role in patient outcome after myocardial revascularization, have not been fully investigated in diabetic subjects. Therefore, we sought to determine the influence of adult-onset diabetes on vasoreactivity and morphological profile of venous and arterial grafts. Of the 160 consecutive patients enrolled in the study, 90 were diagnosed with type 2 diabetes and 70 did not have diabetes (control group). All patients underwent evaluation of glucose control before surgery. Tissue specimens were collected from left internal thoracic artery (LITA) and saphenous vein (SV) grafts harvested during elective CABG. Functional tests were performed to assess contractile and vasodilative responses of bypass conduits. Histological evaluation was carried out to examine vessel wall structure. Univariate and multivariate analyses were performed to correlate the preoperative factors related to the control of the endocrine disorder with histological findings. Patient medical history and demographics did not differ between the groups. Diabetic patients showed significant microalbuminuria and higher plasma levels of C-peptide and GHb as compared with nondiabetic subjects. Functional tests of the LITA segments revealed no difference between groups with regard to contractile and vasodilative responses. In contrast, significant impairment in the endothelium-related vasodilation of the SV grafts was observed in diabetic subjects. Histological studies showed structural preservation of the arterial conduits in both groups. However, marked intimal abnormalities (also atherosclerotic calcified plaques) were detected in SV grafts harvested from diabetic patients. Logistic regression analysis showed that high levels of proteinuria and GHb were independent predictors of advanced structural degeneration of SV conduits. Treatment modality, duration of diabetes, and other demographic or metabolic factors were found to have no influence on the morphological characteristics of SV conduits. In conclusion, biological properties of LITA conduits for CABG were preserved in diabetic patients. However, these patients frequently showed impairment of the endothelium-dependent vasorelaxation and intimal degeneration of SV grafts. The extent of structural abnormalities of SV grafts was inversely correlated with the efficacy of the metabolic control of the endocrine disorder. Further studies are required to conclusively correlate preoperative SV graft abnormalities with postoperative conduit patency rate and the occurrence of adverse cardiac-related events in diabetic subjects.
[Show abstract][Hide abstract] ABSTRACT: histologic detection of shows high diagnostic accuracy in chronic nonatrophic gastritis. However, when atrophy occurs, the sensitivity of bacterial detection varies. This study assessed the routine histologic sensitivity for current infection in patients with atrophic gastritis, with and without intestinal metaplasia.
five hundred and ten consecutive patients with diffuse chronic atrophic gastritis, with (174 cases) and without (336 cases) intestinal metaplasia, were investigated following the Sydney System recommendations. In cases with negative tissue staining for Helicobacter-like organisms, serum immunoglobulin G (IgG) antibodies to were assayed.
the overall rate of positive staining for Helicobacter-like organisms was 51.8% (264 of 510 cases), 62.8% and 30.4% in cases without and with intestinal metaplasia, respectively. Serum IgG antibody determination was consistent with current infection in 180 (73.2%) of the 246 cases with negative histology. detection rate was significantly lower ( < 0.01) in Grade 3 than in Grade 1 atrophy. When intestinal metaplasia was present, histologic bacterial detection progressively decreased, from 46.3% to 20%, depending on severity. infection was found by histology in 42.2% and in 56.2% of cases with inactive and active disease, respectively. Overall, the diagnostic accuracy of histology was significantly lower ( <0.001) than that of histology combined with serology.
most (87.1%) diffuse chronic atrophic gastritis patients showed serum antibody IgG levels consistent with current infection, although histology was positive in only 59.5% of cases. Gastritis activity and current infection did not ever correlate in the presence of mucosal atrophy and/or intestinal metaplasia. Routine biopsy sampling, hematoxylin and eosin staining, and Giemsa staining therefore underestimated the true prevalence of infection.
No preview · Article · Sep 2002 · Journal of Clinical Gastroenterology
[Show abstract][Hide abstract] ABSTRACT: High doses of ethanol increase stroke risk: in this context, a role for excitatory amino acids has been proposed. The present results show that, in frontoparietal cerebral cortex, chronic ethanol treatment (10% v/v in drinking water for 28 days) was able to slightly reduce glutamate release (evaluated through transdialysis coupled with high-pressure liquid chromatography) following focal ischemia as regards non-treated ischemic rats. This reduction was, however, not associated with decreased cerebral damage. In 24-h withdrawing rats, histological and morphometric analyzes showed an exacerbated cerebral damage coupled with higher glutamate and aspartate release compared to controls. These results suggest that adaptive changes following chronic ethanol consumption lead to an increased excitotoxicity that is particularly evident during the withdrawal condition.
No preview · Article · Aug 2002 · Neuroscience Letters
[Show abstract][Hide abstract] ABSTRACT: To investigate the morphological aspects of blood microvasculature of the skin and subcutaneous tissues in subjects with paraplegia with heterotopic ossification (HO).
In two patients with traumatic spinal cord injury and HO, punch biopsies of skin and hypodermic soft tissue in the region of HO near the hip were studied with histological and ultrastructural methods.
Alterations of endothelial cell and basement membrane of capillaries and small vessels were observed. Hyperactive endothelium, thickening and reduplication of the basement membrane, changes of the perivascular connective tissues and microcalcifications in the subcutaneous fat tissue were also seen.
This present study indicates microvascular changes in the skin and subcutaneous tissue in the region of HO near the hip of two subjects with paraplegia. In our opinion the described vascular changes may induce hypoxiemic alterations of the soft para-articular tissues leading metabolic changes which may contribute to the development of HO. Therefore, it cannot be concluded whether these changes are directly responsible for HO induction.
[Show abstract][Hide abstract] ABSTRACT: Focal ischemia was induced in the fronto-parietal region of rat brain, by injection of Rose Bengal, followed by light activation. Focal ischemia was accompanied by formation of PGD2 peaking 60–90 min post irradiation and declining thereafter. Increased Cycloxygenase-2 (COX-2) expression was also observed. Control ischemic rats showed distinct morphological alterations with necrosis of neurons, glial cells and blood vessels, surrounded by a halo with pyknotic cells with cytoplasm swelling and vacuolization. Compound SC58236, a selective COX-2 inhibitor, dose-dependently prevented, ischemia-induced eicosanoid formation (area under the curve (AUC) of controls: 3.11±0.87; AUC of 20 mg/kg SC58236: 0.39±0.24), and caused significant reduction of damaged area (30.7 and 18.9% at SC58236 20 and 6.6 mg/kg), suggesting that selective inhibitors of COX-2 are neuroprotective.
No preview · Article · Jun 2001 · Neuroscience Letters
[Show abstract][Hide abstract] ABSTRACT: Epidemiological studies show that chronic ethanol consumption at high doses enhances the risk of cerebral stroke. The mechanisms responsible for the greater vulnerability of alcoholics' brains to stroke have to be completely understood, but a role for excitatory amino acids has been suggested. In order to study the interaction between alcohol and ischemia, we investigated the effect of acute alcohol administration in a model of focal cerebral ischemia. In particular, we evaluated the release of glutamate and aspartate from the cerebral frontal cortex by a transdialysis technique. Alcohol was acutely administered at 1.5 and 3.0 g/kg ip. During the period of maximal alcoholemia, ethanol almost abolished the ischemia-induced release of glutamate leading to glutamate values around or below the basal. Aspartate levels were unaltered both following ischemia and alcohol+ischemia. The decrease in glutamate release, however, was not accompanied by a significant reduction of the extension of the damaged area assessed by histological analysis.
[Show abstract][Hide abstract] ABSTRACT: Changes in prostanoids concentration and effects of the non-specific COX inhibitor indomethacin on prostanoids levels and extension of tissue damage were studied following focal ischemia induction in the fronto-parietal region of rat brain. Ischemia was induced in animals bearing a transcerebral microdialysis probe by injection of Rose Bengal, a photosensitive dye, followed by light activation. Prostanoid levels were determined in the dialysate using immunoenzymatic techniques. PGD2 levels rose significantly up to 237+/-22 pg/ml compared to a basal level measured before ischemia induction which was below the detection limit. TXB2 changes were smaller and had a different time course. Treatment with indomethacin abolished the ischemia-induced PGD2 release and reduced the extent of injury to the area by 43+/-3.7%. These results suggest that prostanoid release may play an important role in neurodegenerative processes and that cyclooxygenase inhibitors may contribute to protect against cerebral tissue damage.
No preview · Article · Jan 1999 · Neuroscience Letters
[Show abstract][Hide abstract] ABSTRACT: Vascular deafferentation of the Latissimus Dorsi Muscle (LDM) for dynamic cardiomyoplasty is an important cause of ischemia in the distal portion of the muscle with degeneration of muscle fibres and consequent reduction in the effectiveness of the surgery. Experimental studies suggest that a vascular delay procedure and a 10-day delay adaptation significantly improve the distal perfusion and function of the LDM flap for cardiomyoplasty. We here report a comparative histological and ultrastructural study of biopsies from unconditioned LDM flaps of two patients, taken 30 days after vascular deafferentation and dynamic cardiomyoplasty, and 10 days after a vascular delay procedure, respectively. In the first case, in the distal part of LDM we found muscle atrophy and degeneration, necrosis of capillaries, with swelling of endothelial cells and disruption of cytoplasmic organelles, and capillary neoangiogenesis. In the second patient, the distal LDM after vascular delay procedure show minimal muscle fibre degeneration, dilatation of capillaries with endothelial cell preservation, and scarce capillary neoangiogenesis. The present results seem to confirm that a vascular delay procedure on LDM for use with cardiomyoplasty may improve the LDM perfusion and function, inducing moderate morphological changes in muscle fibres and vasculature in comparison to the deafferentated LDM.
Preview · Article · Jan 1999 · Basic and applied myology: BAM
[Show abstract][Hide abstract] ABSTRACT: We report the case of a 67-year-old male patient who presented with melaena and acute anaemia. Upper digestive tract endoscopy and computed tomography of the abdomen showed a centrally ulcerated, broad-based, polypoid projection of 4 cm in the gastric antral wall. Although endoscopic biopsies were negative for neoplastic changes, the patient underwent distal gastrectomy with Billroth-I reconstruction. Histological and immunohistochemical studies on the surgical resection specimen revealed a gastrointestinal stromal tumour (GIST) of combined smooth muscle and neural type, with no evidence of mitotic activity but of uncertain biological behaviour. After serological detection, Helicobacter pylori eradication was recommended to prevent bacterial damage of the gastric remnant.
No preview · Article · Oct 1998 · European Journal of Gastroenterology & Hepatology
[Show abstract][Hide abstract] ABSTRACT: Initial lymphatic vessels of the human urinary bladder mucosa undergo morphological changes following different functional organ conditions. At low volume/pressure condition (median volume of 50 ml and median intraluminal pressure of 5 cm H2O), initial lymphatics have a very attenuated endothelial wall and an evident lumen. Simple contacts join endothelial cells one to another. At higher volume/pressure condition (median volume of 300 ml and median intraluminal pressure of 15 cm H2O)), the vessels display an irregular and indented profile with a reduced lumen. Morphological changes correspond to collapsed and distended vesical walls occurring at the different volume/pressure conditions. These findings suggest that distension of the bladder wall may produce a tissue pump mechanism promoting the lymph flow in the initial lymphatics.
[Show abstract][Hide abstract] ABSTRACT: The ability of urothelial tumors of the urinary bladder to metastasize via the lymphatic circulation and the extent of metastatic involvement of regional lymph nodes is an important parameter in the staging and prognosis of these neoplasms. Accordingly, we examined the site and morphology of initial lymphatic vessels in the mucosa of the human urinary bladder in patients with invasive transitional cell carcinoma. Lymphatics in the papillary tumoral mass was also examined. Endoscopic transurethral biopsies from the urinary bladder of 120 patients with invasive transitional cell papillary carcinoma were utilized for this study. Biopsy from the uninvolved lateral wall of the same patient was utilized as a control. On histopathology of biopsies of neoplastic tissues, initial lymph vessels were seen in the deeper region of the mucosa but not in the subepithelial layer nor in the stroma of the tumoral papillae. The latter were often associated with arteriolar and venular vessels. When edema and inflammation occurred in peritumoral regions, lymphatics showed a dilated lumen, non-indented wall with dissociated perivascular collagen and elastic fibers. Tumoral permeation or embolization of lymphatics was seen in 12% of patients with invasive tumors, and these lymphatic vessels did not display significant morphologic changes. The absence of initial lymphatics in the stroma of tumoral papillae and in infiltrated subepithelial regions of the urinary bladder may explain the absence of lymph node metastasis in early-stage invasive urothelial tumors.
[Show abstract][Hide abstract] ABSTRACT: The localization, morphology and fine structure of initial lymphatic vessels in the mucosa of the empty and distended urinary bladder were studied. Endoscopic transurethral biopsies of the empty (collapsed) bladder showed under light and electron microscopy numerous intramural lymphatics with a dilated lumen and thin profile. Contacts between endothelial cells were single, overlapping, interlocking, and open while the perivascular connective tissue was filled by fascicles of collagen fibers. In the most superficial layer (subepithelial mucosa), lymphatics were not seen. Biopsies obtained under elevated intraluminal pressure and distension showed on light and electron microscopy lymphatic vessels with small lumens characteristically reduced to irregular slits. Endothelial cell contacts were simple or overlapping; open junctions were rare. The perivascular connective tissue was dense and collagen and elastic fibers often abutted one another. These findings support that with a distended or expanded urinary bladder, the effect of increased intraluminal pressure on the superficial (mucosal) layer radially pulls on the connective tissue that in turn compresses the initial lymphatics thereby restricting lymph transport.
[Show abstract][Hide abstract] ABSTRACT: A 48-year-old female with a history of accentuated dyspnea, pleural thickening in anteromedial portion with left patchy parenchymal shadowing invading adjoining parasternal structure of the rib cage, presented 13 months later marked superclavicular, anterior mediastinic and parahilar left lymphadenopathy. Open surgical biopsies on the pleural lesion invading the hypodermic tissues of parasternal region showed morphological and immunocytochemical patterns of Langerhans' cell histiocytosis (LCH). 13 months later the superclavicular lymph node biopsy diagnosed Hodgkin's lymphoma (HD), mixed cellularity type II, stage AE. On a total of 29 cases with association of LCH and HD, the described case in the second case that shows morphologically demonstrated LCh with subsequent development of HD. It is postulated that the development of HD in a patient with LCH, might represent malignant evolution of this hyperplastic process.
[Show abstract][Hide abstract] ABSTRACT: It has been suggested that there may be a correlation between Helicobacter pylori (Hp) infection and precancerous lesions of the stomach. However, histological evaluation of bacterial colonization in chronic atrophic gastritis shows a relatively low prevalence of the microorganism, which does not support the hypothesis. The aim of our study was to investigate the Hp serology in 95 patients with chronic gastritis with antral atrophy, with (27 cases) and without (68 cases) intestinal metaplasia, and without Helicobacter-like organisms in antral and corpus biopsy specimens. For all subjects, serum anti-Hp immunoglobulin IgG was identified by a fluorescent immunoenzymatic method (Helori-test; Eurospital), and mucosal atrophy and activity were graded histologically (Sydney System score). The serum Hp-antibody status documented the presence of current bacterial infections in 64 of 95 (67.4%) patients and previous infections in another 17 subjects. In only 14.7% of cases was there no evidence of current or previous infection. These subjects had less severe mucosal atrophy and lower inflammatory scores. In addition, there were no cases of intestinal metaplasia in such subjects. The high prevalence of Hp infection confirms the primary role of the microorganism in the pathogenesis of chronic gastritis with antral atrophy, although the bacterium is no longer present in the advanced stages of such disease. The histological evaluation of Hp colonization following the criteria of the Sydney System appears from our study to underestimate the true prevalence of the infection in the stomach when there is mucosal atrophy.
No preview · Article · May 1996 · Journal of Clinical Gastroenterology
[Show abstract][Hide abstract] ABSTRACT: Thymectomy is often an extremely useful therapeutic procedure in myasthenia gravis (MG) and is usually indicated for adult patients with generalized disease. Because remnants of thymus may remain in extrathymic fat, an extended thymectomy is recommended. A new surgical approach without sternotomy: video-assisted thoracoscopic extended thymectomy (VATET) was performed in 30 MG patients. The weight of removed thymus ranged from 10.8 to 113 grams. The weight of fatty tissue removed from pretracheal, anterior mediastinal and costophrenic areas ranged from 6.3 to 74.8 grams. Histological examination revealed thymic remnants in 14.8% of pretracheal fat samples and in 33.3% of samples from anterior mediastinal plus costophrenic areas. These findings indicate that VATET is a radical procedure and may be the first choice surgery for young female MG patients, since aesthetic sequelae are reduced compared to procedures involving sternotomy.
No preview · Article · Jan 1996 · International surgery