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Notes: Summary In four patients with presenile Alzheimer's disease (AD) and three age-matched controls a quantitative study of neurons and neurofibrillary tangles (NFT) in the substantia nigra (SN) and nucleus centralis superior (NCS) was performed. A significant neuronal loss, similar in both nuclei, was found in AD cases, while the incidence of NFT was remarkably higher in NCS. Moreover, no significant correlation between neuronal loss and number of NFT was detected. An electron-microscopic study revealed that the subcortical NFT in NCS are made up of paired helical filaments in spite of their globose round shape.

Notes: Langerhans cells can originate in vitro from immature precursors stimulated with granulocyte macrophage-colony-stimulating factor (GM-CSF), tumour necrosis factor (TNF)-α and stem cell factor (SCF). We asked whether these cytokines also control the differentiation state of Langerhans cells within the epidermis and upon leaving this tissue. We harvested sheets of human epidermis by controlled dispase hydrolysis of keratomes, cultured them in RPMI and 10% fetal calf serum for 48 h and analysed the sheets and the cells migrated spontaneously into the medium, most of which were Langerhans cells containing Birbeck granules.1 By flow cytometry, the intensity of CD1a expression was reduced quite evenly among Langerhans cells migrated from sheets within 48 h. The cells in the sheets underwent loss of dendrites, with a significant reduction in the cell perimeter that was prevented by GM-CSF and TNF-α together. Either of these cytokines induced expression of CD18 by cells in the sheets and those in the medium. Moreover, TNF-α induced expression of CD54 by cells in the medium, but not by those retained in the sheets, whereas human SCF induced, dose dependently, expression of CD54 by cells in the sheets, but not from those in the medium.2 The proliferation of allogeneic lymphocytes was much higher when stimulating Langerhans cells were harvested from cultures with any cytokine, rather than from cultures without cytokines. We conclude the following: (i) GM-CSF and TNF-α help to maintain full differentiation of Langerhans cells within the epidermis; (ii) cytokine influence on Langerhans cells adhesiveness is in part context dependent; and (iii) pretreatment with cytokines influences positively the number or accessory activity of Langerhans cells on lymphocytes during subsequent mixed leucocyte reaction.

Notes: The structure of human terminal ileum mucosa was studied both after total colectomy and conventional ileostomy and after total colectomy and ileo-rectal anastomosis. Villous height, gland depth, number of mitoses, relative density of goblet cells and types of mucins secreted were microscopically evaluated in ileal biopsy specimens from 24 patients a minimum 6 months after surgery. Subtotal villous atrophy with glandular hypertrophy was demonstrated after both surgical procedures. The degree of villous atrophy and glandular hypertrophy was not dependent either on the disease for which surgery was performed, nor on the duration of the post-surgical period. Villous atrophy and glandular hypertrophy appeared greater in ileo-rectal anastomosis specimens than in those from ileostomy. Goblet cell density did not seem to be affected by total colectomy. After surgery no changes in the types of mucins secreted were shown by the histochemical techniques employed. This light microscopical study did not provide any evidence of increased ileal absorptive surface after total colectomy.

Notes: In view of the critical role of dendritic cells in immune mediated skin diseases, we have investigated the membrane antigen patterns and ultrastructure of cutaneous dendritic cells in eight patients with chronic discoid lupus erythematosus and five with subacute cutaneous lupus erythematosus. In the lesional epidermis, the expression of HLA-DR antigens by epidermal dendritic cells was reduced, as compared with perilesional, clinically normal skin. In addition, only few CD1a+ dendritic cells (Langerhans' cells), along with some CD11c+ and CD14+ cells (presumable precursors of Langerhans' cells), were found in atrophic areas of lesional epidermis. In contrast, the number of Langerhans' cells in non-atrophic areas of lesional epidermis was similar to that in perilesional skin. On electronmicroscopy, epidermal Langerhans' cells appeared depleted of organelles and dendrites and contained tubuloreticular inclusions. In the lesional dermis, both CD1a+ and CD36+ dendritic cells were found, associated with CD4+ and CD8+ T-cells, respectively. Moreover, CD11c+ and CD14+ cells were found around capillaries in the papillary dermis on electronmicroscopy. Indeterminate cells (dendritic cells with features of Langerhans' cell lineage, but apparently without Birbeck granules) and dendritic macrophages were found, associated with lymphocytes and mast cells. No cells with intermediate/transitional features between these two dendritic cell types were found. Conversely, peculiar dendritic cells—with short and blunt dendrites and cytoplasm containing many flat, rough cisternae, moderately well developed Golgi apparatus and no lysosomes—were found in the same location as the CD11c+ and CD14+ cells identified by light microscopy. These findings might be interpreted as follows: 1 the alterations in cytological differentiation and expression of functionally meaningful molecules by epidermal Langerhans' cells in cutaneous lupus erythematosus lesions suggest an impairment of their immunological efficiency; 2 in the lesional dermis of cutaneous lupus erythematosus, a CD4+ T-cell/CD1a+ dendritic cell-based, delayed-type immune response is possibly modulated by a suppressor T-cell circuit in which CD36+ dendritic cells may act as accessory cells; 3 CD11c+ and CD14+ cells with peculiar ultrastructure are possible precursors of both CD1a+ indeterminate cells and CD36+ dermal dendrocytes in the dermis.

Notes: The dermal infiltrates of four patients with the Sézary syndrome were studied by electron microscopy and the data were evaluated quantitatively. The nuclear contour index of lymphocytes was calculated, and many tumour cells had an index greater than 6.5. Dendritic cells were found in all cases. The dendritic cells contained smooth and rough endoplasmic reticulum, moderately well-developed Golgi apparatus, scanty lysosomes and many thin and intermediate filaments; their surface was scalloped with numerous vesicles. Birbeck granules were not found in the cytoplasm of dendritic cells. Dendritic cells comprised 24% of infiltrating cells and were interspersed with lymphocytes; 75% of the lymphocytes were in contact with dendritic cells; 35% of the lymphocytes in contact with dendritic cells had a nuclear contour index higher than 6.5 and 76% had a nuclear contour index higher than 5. The data strongly suggest a functional relationship between lymphocytes and dendritic cells in the dermal infiltrate of Sézary syndrome. They are discussed in relation to the hypothesis that the disease is a consequence of chronic immune stimulation.

Notes: Ordered array of dendritic cells and CD8+ lymphocytes in portal infiltrates in chronic hepatitis C Aims: Despite the importance of dendritic cells in stimulating primary and secondary immune responses by presenting antigens to T-lymphocytes in draining lymph nodes and peripheral tissues, respectively, very limited information is available on the presence and localization of these cells in hepatitis C virus (HCV)-related chronic active hepatitis. Therefore, we addressed the ultrastructure, immunophenotype, distribution and relationships to lymphatics of dendritic cells in portal infiltrates of this disease. Methods and results: Part of percutaneous diagnostic liver biopsies (Knodell’s histological assessment index: 9–13) was processed for electron microscopy and for immunohistochemical detection of immune system cell membrane antigens and of the lymphatic endothelium marker podoplanin. In portal infiltrates, cells with electron microscopical and cell marker features of dendritic cells and expressing the activation markers CD54, CD80, CD83 and CD86 were organized in a discontinuous network, that embedded CD8+ lymphocytes in close contact with dendritic cells and came in contact with hepatocytes, sometimes infiltrating beyond the limiting plate. Also, dendritic cells were found within newly formed lymphatic capillaries in thin, infiltrated septa among hepatocytes. Conclusions: This evidence strongly suggests a critical role of dendritic cells and newly formed lymphatics in the pathogenesis and organization of the immune infiltrate that characterizes HCV-related chronic active hepatitis.

Notes: Background:  Trans-catheter arterial chemoembolisation (TACE) is the most common palliative treatment for hepatocellular carcinoma (HCC). The therapeutic options depend both on the characteristics of the tumour and on functional staging of the cirrhosis.Aim:  To evaluate the effects of TACE on the survival of cirrhotic patients with HCC according to different staging systems [Okuda score, Cancer Liver Italian Program (CLIP) score, Model for End-stage Liver Disease (MELD) score] and in relation to the side-effects of TACE.Methods:  Fifty cirrhotic patients, 36 CTP class A and 14 class B, underwent 106 TACE treatments with mitoxantrone. Survival at 12, 24, and 36 months was evaluated.Results:  MELD at 12 months and CLIP at 24 months were identified as significant variables associated with survival. Combined cut-offs of CLIP and of MELD identified four subgroups of patients with different survivals, at 12, 24 and 36 months, respectively: CLIP ≥ 2 and MELD ≥ 10 (63%, 20% and 0%), CLIP 〈 2 and MELD ≥ 10 (73%, 40% and 22%), CLIP ≥ 2 and MELD 〈 10 (73%, 40% and 22%) and CLIP 〈 2 and MELD 〈 10 (100%, 63% and 50%). Post-TACE side-effects proved to have no influence on survival.Conclusion:  In patients with poor probability of survival (CLIP ≥ 2 and MELD ≥ 10), TACE must be planned with a great deal of caution, while in patients with possibly good outcomes (CLIP 〈 2 and MELD 〈 10), more ‘aggressive’ therapy should be taken into consideration.

Notes: Helicobacter pylori gastric infection has been associated with various digestive and extra-digestive diseases. The systemic influence of gastric H. pylori infection seems to be mediated by the release of various cytokines. In liver disease, bacterial infections have been associated with the impairment of liver metabolic function.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:To evaluate the influence of H. pylori infection on liver function as assessed by means of the monoethylglycinexylidide test, which depends upon liver blood flow and cytochrome P-450 activity, and the 13C-galactose breath test, which depends on cytosolic enzymatic activity and is correlated with hepatic functional mass. Moreover, to evaluate whether H. pylori-associated modifications of liver function may be related to tumour necrosis factor-α serum levels.〈section xml:id="abs1-3"〉〈title type="main"〉Patients and methods:Thirty-five patients with liver cirrhosis of various aetiologies, who underwent monoethylglycinexylidide and 13C-galactose breath tests, were retrospectively evaluated for H. pylori infection by means of anti-H. pylori immunoglobulin G. The main clinical, biochemical and functional characteristics of the patients as well as their tumour necrosis factor-α serum levels were then analysed on the basis of the presence of H. pylori infection.〈section xml:id="abs1-4"〉〈title type="main"〉Results:Twenty-one patients tested positive for H. pylori infection (60%), and 11 tested negative (31.4%). No clinical or biochemical differences were observed between H. pylori-infected and non-infected patients. H. pylori infection showed no difference in distribution according to Child–Pugh classes (A, 55%; B and C, 67%). The monoethylglycinexylidide test results were significantly lower at each sampling time in H. pylori-positive patients compared to H. pylori-negative patients (MEGX15, P=0.027; MEGX30, P=0.014; MEGX60, P=0.028), while 13C-galactose breath test showed no significant differences considering both cumulative percentage dose and percentage dose/h. The median tumour necrosis factor-α serum levels were no different between H. pylori-positive (16.1 pg/mL, 95% confidence interval, 8.7–28.7) and H. pylori-negative (12.3 pg/mL, 95% confidence interval, 8.7–23.4) patients.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:In cirrhotic patients, H. pylori infection seems to selectively affect cytochrome P-450 liver activity, while hepatic functional mass does not seem to be impaired. Tumour necrosis factor-α does not seem to be the mediator of this impairment. Further studies are needed to evaluate the impact of H. pylori eradication on parameters of liver function.

Notes: There are few data on the use of the 13C-aminopyrine breath test to evaluate the severity of disease in patients with hepatitis C virus-related chronic liver disease, although these patients represent one of the most important problems in clinical hepatology.〈section xml:id="abs1-2"〉〈title type="main"〉Aims:To compare 13C-aminopyrine breath test results of patients with hepatitis C virus-related chronic hepatitis and Child–Pugh class A cirrhosis with those of normal subjects, and to evaluate different methods of expressing 13C-aminopyrine breath test results.〈section xml:id="abs1-3"〉〈title type="main"〉Methods:Twenty-four patients with hepatitis C virus-related chronic hepatitis and 17 patients with Child–Pugh class A cirrhosis underwent 13C-aminopyrine breath test. Breath samples were collected every 30 min up to 2 h after 13C-aminopyrine administration. 13C-Aminopyrine breath test results were expressed as a percentage of the administered dose of 13C recovered per hour (% dose/h) and the cumulative percentage of administered dose of 13C recovered over time (% dose cum). Nineteen healthy subjects served as controls. Patients with hepatitis C virus-related chronic hepatitis were divided into subgroups on the basis of histological staging and grading.〈section xml:id="abs1-4"〉〈title type="main"〉Results:The 13C-aminopyrine breath test result (% dose/h) at 30 min was significantly different among the three subgroups of subjects (normal subjects, 11.5 ± 3.5; chronic hepatitis patients, 8.1 ± 4.1; cirrhosis patients, 5.0 ± 3.1; P 〈 0.0005). Moreover, the differences between chronic hepatitis and cirrhosis patients were statistically significant (P 〈 0.03). The fibrosis score showed a significant inverse correlation with the 13C-aminopyrine breath test result (% dose/h) at 30 min (rs=− 0.409, P=0.05). The 13C-aminopyrine breath test result (% dose/h) at 30 min also allowed normal subjects and chronic hepatitis patients with low (≤ 2) or high (〉 2) fibrosis scores to be distinguished. The 13C-aminopyrine breath test results (% dose cum) at 30, 60 and 90 min allowed discrimination between normal subjects and chronic hepatitis and cirrhosis patients. The 13C-aminopyrine breath test result (% dose cum) was also able to distinguish between normal subjects and chronic hepatitis patients with high but not low fibrosis scores. Both 13C-aminopyrine breath test results (% dose/h and % dose cum) at 120 min allowed the differentiation between normal subjects and chronic hepatitis patients with high (≥ 6) necro-inflammatory activity.〈section xml:id="abs1-5"〉〈title type="main"〉Conclusions:In patients with hepatitis C virus-related chronic liver disease, the 13C-aminopyrine breath test proved to be safe and easy to perform, and was able to evaluate different degrees of liver function impairment which were partly correlated to clinical and histological evaluation. In future studies, 13C-aminopyrine breath test results should be expressed in a standardized fashion to permit comparison.