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L Montella

Publications and source records attributed to L Montella.

15 recordsLinked to original sources

Persistent Cryptococcus neoformans pulmonary infection in the rat is associated with intracellular parasitism, decreased inducible nitric oxide synthase expression, and altered antibody responsiveness to cryptococcal polysaccharide.

Fungal pathogens are notorious for causing chronic and latent infections, but the mechanism by which they evade the immune response is poorly understood. A major limitation in the study of chronic fungal infection has been the lack of suitable animal models where the infection is controlled and yet persists. Pulmonary Cryptococcus neoformans infection in rats results in a diffuse pneumonitis that resolves without dissemination or scarring except for the persistence of interstitial and subpleural granulomas that harbor viable cryptococci inside macrophages and epithelioid cells. Infected rats are asymptomatic but remain infected for as long as 18 months after inoculation with C. neoformans. Containment of infection is associated with granuloma formation that can be partially abrogated by glucocorticoid administration. Using this model, we identified several features associated with persistent infection in the rat lung, including (i) localization of C. neoformans to discrete, well-organized granulomas; (ii) intracellular persistence of C. neoformans within macrophages and epithelioid cells; (iii) reduced inducible nitric oxide synthase expression by granulomas harboring C. neoformans; and (iv) reduced antibody responses to cryptococcal polysaccharide. The results show that maintenance of persistent infection is associated with downregulation of both cellular and humoral immune responses.

Adrenal Cortex Hormones↗

Endobronchial metastasis from stomach carcinoma.

We describe the case of a 57-yr-old female with endobronchial metastasis from stomach carcinoma. Respiratory symptoms began 3 months before the diagnosis of the gastric cancer. Chest computed tomography revealed a reticular lymphangitic carcinomatosis pattern with hilar and mediastinal lymphadenopathy. Fibreoptic bronchoscopy showed a spread submucosal infiltration which narrowed the apical segment of the left lower lobar bronchus. The biopsy specimen at that level was histologically identical to the gastric primitive cancer. To the authors' knowledge, stomach carcinoma has rarely been reported to give rise to airway metastases.

Bronchial Neoplasms↗

Prevalence, age distribution and aetiology of bronchiectasis: a retrospective study on 144 symptomatic patients.

The incidence of bronchiectasis (BCT) has probably decreased in developed countries in recent years, but reliable statistical data on its occurrence are still lacking. The aim of the present study was to retrospectively evaluate the prevalence, age distribution and aetiology of BCT, diagnosed in a selected series of symptomatic patients of a Western country by using bronchography. The authors analysed the main known predisposing and associated conditions (PACs), and the occurrence and age distribution of BCT in 144 consecutive patients who underwent bronchological examination (fibreoptic bronchoscopy and bronchography) in the years 1987-1994 because of recurrent purulent bronchitis and/or haemoptysis. The overall prevalence of BCT was 34% (49/144); its age distribution was: 17.2% (0-10 yrs), 43.7% (11-20 yrs), 38% (21-30 yrs), 37.5% (31-40 yrs), 33.3% (41-50 yrs), 40% (51-60 yrs), and 20% (61-70 yrs). Thirty-one PACs were found in 29/144 patients of the whole study group. The prevalence of BCT was significantly higher in the subgroup of 29 patients with PACs than in the subgroup of 115 patients without PACs (75.9% versus 23.5%; p < 0000001). The aetiology of BCT was mainly unexplained, as it was only possible to detect 24 PACs in 22/49 patients with BCT (44.9%): congenital, genetic and immune disorders (eight), localized airways obstructive diseases (five), pulmonary infections (three), bronchial asthma (two), pulmonary lobar fibrosis (two), ulcerative colitis (two), dermatomiositis (one), and toxin inhalation (one). The authors conclude that bronchiectasis still occurs in a large percentage of symptomatic patients of a developed country in the post-antimicrobial era, especially in the second to sixth decades, as well as in the presence of predisposing and associated conditions; its aetiology remains unknown in more than half of cases.

Adolescent↗

Role of surgery in thymic disorders.

Thymomas are relatively slow-growing neoplasms that should be considered malignant tumours. When treated in the early stages, however, they have an excellent prognosis for long-term survival. Surgery, radiation therapy and chemotherapy all play a role in the management of these neoplasms. Surgery is the treatment of choice in thymoma patients and has become an increasingly accepted procedure in the treatment of myasthenia gravis (MG) since 1936, when thymectomy was performed for this disease for the first time. Improvement in myasthenic symptoms is nearly always observed following thymectomy, but the rates of complete remission vary from 7% to 63%. We have studied the potential preoperative factors predicting the evolution of MG.

Female↗

Role of somatostatin analogue-based therapy in unresponsive malignant thymomas.

Thymomas are rare neoplasms that are usually associated with parathymic syndromes, pure red cell aplasia, myasthenia gravis, hypogammaglobulinaemia and other mainly immunological disorders. Therefore, the management of thymoma patients is often complex and presents many diagnostic and therapeutic issues. Controversies concerning the definition of the histological subtypes and the role played by thymoma-associated syndromes are of primary importance in determining the oncological approach. Although low-stage thymomas have a high percentage of recovery, thymomas which are locally advanced, metastatic or previously treated with standard therapeutic options have no well-defined and effective treatment approaches. The data previously described by us on somatostatin receptor scintigraphy showing high uptake of indium-labelled octreotide by thymic masses and the successful treatment of a patient with thymoma and pure red cell aplasia with octreotide and prednisone has provided us the rationale for using such treatment in patients with advanced thymoma.

Antineoplastic Combined Chemotherapy Protocols↗

Immunological findings in thymoma and thymoma-related syndromes.

Human thymoma is a neoplasm of thymic epithelial cells associated with several clinical syndromes ranging from autoimmune disease to immunodeficiency. The aim of our research was to investigate T cell-mediated immune response in patients with thymoma. Initially eight patients were enrolled in this study. Four patients underwent surgical removal of the thymus, while four were submitted to diagnostic procedures only. Inversion of the CD4:CD8 ratio was found in three patients. Only one subject displayed a normal CD19 count in peripheral blood. The mean value (+/-SD) of the CD19 percentage in the patient group was 2 +/- 2.2. Notably, the patients with thymoma had fewer mature B lymphocytes than the thymectomized patients. The T-cell receptor (TCR) repertoire was investigated in three individuals affected by thymoma: one underwent thymectomy, while the two others, one of which presented with lymphocytosis, were submitted to diagnostic biopsies only. The preliminary results showed a marked alteration in the CD8 repertoire of the thymectomized patient but not in that of the lymphocytotic patient. However, alterations in the TCR repertoire were also found in one patient with thymoma. Altogether, these preliminary findings reveal that loss of CD19+ lymphocytes in peripheral blood is a frequent phenomena in thymoma patients. In this article we discuss this aspect in the context of alterations of the TCR repertoire.

Adult↗

Phenotypic switching in the human pathogenic fungus Cryptococcus neoformans is associated with changes in virulence and pulmonary inflammatory response in rodents.

High-frequency reversible changes in colony morphology were observed in three strains of Cryptococcus neoformans. For one strain (SB4, serotype A), this process produced three colony types: smooth (S), wrinkled (W), and serrated (C). The frequency of switching between colony types varied for the individual colony transitions and was as high as 10(-3). Mice infected with colony type W died faster than those infected with other colony types. The rat inflammatory response to infection with colony types S, W, and C was C > S > W and ranged from intense granulomatous inflammation with caseous necrosis for infection with type C to minimal inflammation for infection with type W. Infection with the various colony types was associated with different antibody responses to cryptococcal proteins in rats. Analysis of cellular characteristics revealed differences between the three colony types. High-frequency changes in colony morphology were also observed in two additional strains of C. neoformans. For one strain (24067A, serotype D) the switching occurred between smooth and wrinkled colonies. For the other strain (J32A, serotype A), the switching occurred between mucoid and nonmucoid colonies. The findings indicate that C. neoformans undergoes phenotypic switching and that this process can affect virulence and host inflammatory and immune responses. Phenotypic switching may play a role in the ability of this fungus to escape host defenses and establish chronic infections.

Animals↗

Interferon alpha-2b at low doses as long-term antiangiogenic treatment of a metastatic intracranial hemangioendothelioma: a case report.

We describe a case of intracranial haemangioendothelioma in a 20-year old female patient who presented severe neurological symptoms and relapsed after two surgical interventions. The patient was treated with low doses of recombinant interferon alpha-2b (1 MUI three times a week) after surgical resection which led to recovery of daily function and work activity. To our knowledge, this is the ninth patient reported with intracranial hemangioendothelioma, but the only one having diffuse and painful bone metastases resolved by treatment with interferon. After 30 months the patient is free from symptoms and recurrence. The effectiveness shown by recombinant interferon alpha-2b against vascular neoplasms prompted us to look for the possible biological basis of such a property.

Adult↗