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Biomedical subjects

T Lotti

Publications and source records attributed to T Lotti.

At least 109 records · Page 6Linked to original sources
PubMed1990

Cutaneous and plasma fibrinolytic activity in systemic sclerosis. Evidence of normal plasminogen activation.

Eleven patients with systemic sclerosis (SSc) were studied for plasma and cutaneous fibrinolytic activity, residual (potential fibrinolysis) fibrinolytic activity (FA) fo the dermal vessels that is related to the endothelial storage of plasminogen activators that become available due to particular stimuli such as intradermic injection of histamine, and the serum levels of circulating von Willebrand antigen, antithrombin III, plasminogen, beta-thromboglobulin, and platelet aggregate ratio (PAR). Cutaneous FA (autohistographic fibrin film method) appeared normal or increased in non-affected skin, normal in lesional skin, and increased after intradermal (i.d.) injection of 0.1 ml of 0.01% histamine. Monoclonal antibodies directed against the catalytic site of tissue type plasminogen activator completely blocked the fibrinolytic activity, while anti-urokinase antibodies did not abolish the lysis areas. Plasmatic FA, euglobulin lysis time test, (ELT) and the levels of beta-thromboglobulin resulted similar to the controls. A significant increase in von Willebrand Factor VIII antigen (but not of Factor VIII coagulant) was observed in the patients (p less than 0.01). Platelet aggregate ratio, levels of plasma plasminogen and Antithrombin III showed a significant difference (p less than 0.01) when compared with the control subjects. Data suggest that primary injured microvessels in SSc are likely to be arteriolae while venulae could be affected by secondary hypoxia due to the arteriolar damage with consequent release of tissue type plasminogen activator. Therefore, the authors suggest that the fibrinolytic potential is maintained in SSc and that the fibrinolytic therapy should not be used in all patients with SSc but only in those cases with documented exhaustion of plasmatic and/or cutaneous FA.

Adolescent↗
PubMed1990

Antipsoriatic therapies inhibit epidermal plasminogen activator activity.

Urokinase (UK, Mr 55,000) and tissue-type plasminogen activator (tPA, Mr 74,000) are serine proteinases involved in many biological processes, ie, cell migration, neoplastic transformation, and extracellular proteolysis. Cutaneous fibrinolytic activity (dependent on the activity of UK and tPA) was studied with the autohistographic fibrin film method in 40 patients affected by psoriasis vulgaris before and after topical (anthralin, betamethasone valerate, hydrocolloid occlusive dressing) or systemic psoralen-ultraviolet-light (PUVA) treatments. Autohistographic studies also were performed after apposition of monoclonal antibodies directed against the catalytic site of UK and tPA. Finally, UK and tPA were localized immunohistochemically in the psoriatic plaques and in controls using the immunoperoxidase procedure based on the biotin/avidin system. UK and tPA immunoreactivity was present in the cytoplasm and around the outlines of keratinocytes in the psoriatic patches before treatment and in the patches not cleared after treatment, while it was not detectable in normal epidermis, in the unaffected psoriatic epidermis, and in the cleared psoriatic skin. Cutaneous fibrinolytic activity was present in the cases in which UK and tPA were detected histochemically and, in the psoriatic epidermis, it was abolished by preincubation with anti-tPA but not with anti-UK antibodies. This study suggests that established topical and systemic treatments for psoriasis possess UK and tPA antagonist activity.

Adult↗
PubMed1990

Immunological abnormalities in a group of patients with limited cutaneous systemic sclerosis and prominent vascular disease.

Antinuclear antibodies, circulating immune complexes, rheumatoid factors and anticardiolipin antibodies were detected in the sera of 17 patients affected by the limited cutaneous subset of systemic sclerosis and marked clinical evidence of ischaemic cutaneous lesions (fingertip ulcerations). This study was designed to evaluate the possible role of anticardiolipin (aCL) antibodies and other immunological disorders in the endothelial damage characteristic of the disease. ACL antibodies were found in 41% of the patients. With the exception of a significant connection with positive rheumatoid factor tests (RIA), no notable associations between anticardiolipin antibodies and antinuclear antibodies, circulating immune complexes (CIC), and other serological abnormalities were found. ACL antibodies did not significantly correlate with the presence of vascular lesions in our patients. However, a role of these antibodies in endothelial damage cannot be excluded, possibly in association with other serum factors such as immune complexes and antinuclear antibodies. A positive connection between the incidence of CIC and the severity of lung perfusion impairment was observed, and the previously reported relationship between anticentromere antibodies and calcinosis was indirectly confirmed.

Adolescent↗
PubMed1990

[Pityriasis rosea-like skin eruptions caused by captopril].

Captopril is an antihypertensive drug that works by inhibiting the angiotensin-converting enzyme and provokes increased levels of plasma quinine. In the case here reported a picture of pityriasis rosea-like reaction is described. The frequency of the observed and reported reactions by captopril suggests a particular caution in the use of this drug.

Captopril↗
PubMed1990

Reduced angiotensin converting enzyme plasma activity in scleroderma. A marker of endothelial injury?

Decreased levels of angiotensin converting enzyme plasma activity were found in systemic sclerosis. No relationship with clinical characteristics of the disease and increased von Willebrand factor antigen concentration (a widely accepted marker of endothelial injury) were statistically demonstrated. An inverse relationship between the reduced activity of the enzyme and erythrocyte sedimentation rate was detected (r = 0.410, p less than 0.05). We hypothesize that in systemic sclerosis, angiotensin converting enzyme activity might be affected by a decrease in endothelial production or by interference of circulating factors. Further studies are needed to determine if angiotensin converting enzyme activity could be used as a marker of endothelial injury in scleroderma.

Adolescent↗
PubMed1989

Cutaneous fibrinolytic potential, tPA dependent, is reduced in Behçet's disease.

We report our studies on the cutaneous and plasma fibrinolytic activities (FA) in nine patients with Behçet's disease (BD) as compared with nine normal controls. The euglobulin lysis time of the plasma and cutaneous fibrinolytic activity were determined in these patients. The studies showed that the plasma fibrinolytic activity was reduced in the patients with BD and there was impaired cutaneous fibrinolytic potential, tPA dependent, in those patients with venous and arterial thromboses.

Adult↗
PubMed1989

Plasminogen activators and antiplasmin activity in atopic dermatitis.

Cutaneous deposits of fibrinogen activity in lesional skin, plasmatic fibrinolytic activity, and antiplasmin activity (alpha 2 macroglobulin, alpha 1 antitrypsin and antithrombin III) were evaluated in a group of ten patients with atopic dermatitis and in a sex- and age-matched control group. Plasma fibrinolytic activity was increased in the acute phase of the disease (p less than 0.05). The levels of circulating antiplasmins appeared similar in the patients and the control group. Cutaneous fibrinolytic activity was increased in the acute phase of the disease in 5 of 5 cases, suggesting a role of the fibrinolytic system in the amplification of the inflammatory phenomenon in that phase of the disease. In the chronic lichenified phase, CFA was decreased in 3 of 5 cases leading to an excessive deposit of fibrin in the skin. This could be correlated with the abnormal vascular response (blanching phenomenon). On the basis of these data, the therapeutic use of the antifibrinolytic agents only seems rational in the acute phase of the disease.

Acute Disease↗
PubMed1989

Pachydermoperiostosis (primary hypertrophic osteoarthropathy): report of a case with evidence of endothelial and connective tissue involvement.

A case of pachydermoperiostosis characterised by the presence of finger clubbing, periostosis, sweating of hands and feet is described. Modifications of capillaroscopic pattern and of arteriovenous anastomoses are reported. The periungual border and finger tip tissue showed diffuse endothelial hyperplasia, hyalinosis, and sclerosis with packing of collagen fibres. Electron microscopy showed hypertrophic and activated endothelia (numerous and hypertrophic Golgi complexes, several Weibel-Palade bodies, vesicles of micropinocytosis, and glycogen particles), the basal membrane thickened and reduplicated, perivasal infiltrate in superficial derma, reticulation and segmentary reduplication of basal membrane in arteriovenous shunt. In the perineural connective tissue numerous Luse bodies (long spacing collagen) were evident. The data indicate that in the early phase of pachydermoperiostosis morphological endothelial and collagen fibre abnormalities are present, though there is a normal peripheral blood flow.

Adult↗
PubMed1989

Multicenter comparative study of aztreonam and gentamicin in the treatment of renal and urinary tract infections.

A multicenter comparative study was carried out to evaluate the efficacy of aztreonam and gentamicin in 186 patients with symptomatic renal or urinary tract infections. Patients were divided randomly into two groups: 94 patients received aztreonam 1 g/day intramuscularly and 92 patients received gentamicin 80 mg i.m. twice daily. The clinical and microbiologic results found a single daily dose of aztreonam to be more effective than gentamicin b.i.d. Furthermore, no evidence of side effects was seen with aztreonam. Such results are generally thought to ensure better compliance in outpatients.

Adult↗
PubMed1989

Plasminogen activation in psoriasis.

Plasminogen activation is a widely documented physiological phenomenon in which plasminogen activators (mainly urokinase and tissue type plasminogen activator) transform the zymogen plasminogen into the wide-spectrum proteinase plasmin. We show here that psoriatic epidermis is provided with abnormal plasminogen activator activity, mainly dependent on the activity of tissue type plasminogen activator and that this abnormal activity can be reversed with common topical treatments (i.e. anthralin, and 0.1% betamethasone valerate cream). We also report abnormal immunohistochemical localization of plasminogen, urokinase and tissue type plasminogen activator in psoriatic epidermis which returned to normal after the topical treatments. These data suggest a major role of plasminogen activation in the pathogenesis of psoriasis.

Adult↗
PubMed1989

[Study of filaggrin in psoriasis].

Filaggrin is a histidine-rich basic protein that aggregates keratin filaments in fully differentiated cells of the epidermis. Filaggrin is synthesized in the granular cell layer as a high-Mr phosphorylated precursor, profilaggrin, that is processed to form the lower-Mr product present in cornified cells. The catabolism of filaggrin in stratum corneum produces urocanic acid and carboxylic-pyrrolidone acid that, respectively, absorb UV radiations and support cutaneous hydratation. In this study we evaluated by direct-immunofluorescence and by immunoperoxidase staining using rabbit antihuman filaggrin antiserum localization of filaggrin in psoriatic skin and in normal human skin before and after treatment with anthralin 0.1%, betamethasone 0.05% and hydrocolloid dressing. Antiserum against human filaggrin reacted with tissue sections of normal human skin, staining cells in the granular layer and in the stratum corneum, while no staining of human psoriatic skin sections was observed. After treatments, filaggrin resulted present in those psoriatic skin sections that showed complete clinical remission, while it was not observed in psoriatic patches which did not clear. These studies suggest that human skin filaggrin can be considered a marker of clinical remission of psoriasis.

Adolescent↗
PubMed1988

Colchicine treatment in a case of pachydermoperiostosis with acroosteolysis.

We report a case of pachydermoperiostosis with arthralgia, acroosteolysis, and recurrent staphylococcal folliculitis of the face, treated with colchicine (0.5 mg once daily for the 1st week and 0.5 mg twice daily for the next 3 weeks). The evaluation of arthralgia, hyponchial angle, folliculitis, and pachyderma, performed at basal time and once weekly, showed improvement of symptoms and signs after 7-15 days of treatment. Neutrophilic chemotaxis, evaluated before starting the treatment and after 15 and 30 days of therapy, showed a progressive decrease of the initial very high index. Colchicine provided a beneficial therapeutic response in both inhibiting increased chemotactic activity and in reducing tissular oedema in our patient.

Adult↗