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1.
Sci Total Environ ; 750: 142283, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33182218

RESUMO

The deterioration of monument or building stone materials is mostly due to the growth of black crusts that cause blackening and disaggregation of the exposed surface. This study reports on new oxygen (δ17O, δ18O and Δ17O) and sulphur (δ33S, δ34S, δ36S, Δ33S and Δ36S) isotopic analyses of black crust sulphates formed on building stones in Sicily (Southern Italy). The measurements are used to identify the possible influence of volcanic emissions on black crust formation. Black crusts were mostly sampled on carbonate stone substrate in different locations subject to various sulphur emission sources (marine, anthropogenic and volcanic). Unlike atmospheric sulphate aerosols that mostly exhibit Δ33S > 0‰, here most of the analysed black crust sulphates show negative Δ33S. This confirms that black crust sulphates do not result from deposition of sulphate aerosols or of rainwater but mostly from the oxidation of dry deposited SO2 onto the stone substrate. The δ34S and δ18O values indicate that most of black crust sulphate originates from anthropogenic activities. Δ17O values are found to be related to the sampling location. The largest 17O-anomalies (up to ~4‰) are measured in black crust from areas highly influenced by volcanic emissions, which demonstrates the strong involvement of ozone in the formation of black crusts in volcanically influenced environments.

2.
Artigo em Inglês | MEDLINE | ID: mdl-18058556

RESUMO

A topological classification of most quadruplex structures is proposed, based on two main characteristics: 1) the relative orientation of the strands and 2) the nature of the loops connecting the strands.


Assuntos
Oligodesoxirribonucleotídeos/química , Aptâmeros de Nucleotídeos/química , Modelos Moleculares , Conformação de Ácido Nucleico , Trombina/antagonistas & inibidores
3.
An Med Interna ; 15(12): 650-3, 1998 Dec.
Artigo em Espanhol | MEDLINE | ID: mdl-9972600

RESUMO

We report three patients who developed a generalized rash with oral, genital or perianal ulcerations as a result of acute infection due to HIV. The primary infection was diagnosed by seroconversion (by means of EIA and Western blot techniques). Definitive diagnosis was established on days 52, 85 and 97 after the appearance of the rash. The p24 protein of the HIV was only detected in the early phase of the disorder in the two cases in which this study was carried out.


Assuntos
Infecções por HIV/diagnóstico , Doença Aguda , Adulto , Western Blotting , Humanos , Técnicas Imunoenzimáticas , Masculino , Pessoa de Meia-Idade
4.
Chemosphere ; 91(8): 1130-5, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23411091

RESUMO

Trace elements released in the environment during agricultural practices can be incorporated and accumulated in biological fluids and tissues of living organisms. The assessment of these exposures were carried out investigating lanthanide distributions in blood and exoskeleton samples collected from Emys trinacris turtle specimens coming from sites with anthropogenic discharge in western and south Sicily, along migration paths of many bird species from Africa to Europe. The data show a significant (Rxy=0.72; Rxy>0.67; α=0.025) linear relationship between the size of turtle specimens and the lanthanide contents in blood lower than 0.4 µg L(-1) whereas this relationship disappears in blood with higher lanthanide contents. Comparative evaluations of normalised concentrations show that lanthanides fractionate between blood and exoskeleton inducing antithetical lanthanide patterns therein. These features are more evident in specimens with high lanthanide contents in blood, suggesting that lanthanide accumulations in the exoskeleton can represent the physiological response of E. trinacris to environmental and the further confirmation of relationship occurring between the environmental and the biological fluids.


Assuntos
Exposição Ambiental/análise , Monitoramento Ambiental , Elementos da Série dos Lantanídeos/metabolismo , Tartarugas/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Exposição Ambiental/estatística & dados numéricos , Feminino , Elementos da Série dos Lantanídeos/análise , Masculino , Sicília , Poluentes Químicos da Água/análise , Poluição Química da Água/estatística & dados numéricos
5.
J Hazard Mater ; 186(2-3): 1103-10, 2011 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-21168970

RESUMO

Inhalation of airborne particles can produce crystallization of phosphatic microcrysts in intraaveolar areas of lungs, sometimes degenerating into pulmonary fibrosis. Results of this study indicate that these pathologies are induced by interactions between lung fluids and inhaled atmospheric dust in people exposed to volcanic dust ejected from Mount Etna in 2001. Here, the lung solid-liquid interaction is evaluated by the distribution of yttrium and lanthanides (YLn) in fluid bronchoalveolar lavages on selected individuals according the classical geochemical approaches. We found that shale-normalised patterns of yttrium and lanthanides have a 'V shaped' feature corresponding to the depletion of elements from Nd to Tb when compared to the variable enrichments of heavy lanthanides, Y, La and Ce. These features and concurrent thermodynamic simulations suggest that phosphate precipitation can occur in lungs due to interactions between volcanic particles and fluids. We propose that patterns of yttrium and lanthanides can represent a viable explanation of some pathology observed in patients after prolonged exposure to atmospheric fallout and are suitable to become a diagnostic parameter of chemical environmental stresses.


Assuntos
Exposição Ambiental , Exposição por Inalação , Elementos da Série dos Lantanídeos/análise , Pulmão/química , Erupções Vulcânicas , Ítrio/análise , Algoritmos , Líquido da Lavagem Broncoalveolar , Cromatografia Gasosa , Humanos , Itália , Espectrometria de Massas , Modelos Químicos , Termodinâmica , Radioisótopos de Ítrio/análise
7.
Allergol Immunopathol (Madr) ; 20(1): 3-8, 1992.
Artigo em Espanhol | MEDLINE | ID: mdl-1380767

RESUMO

Substance P is a decapeptide which forms part of the group known as neuropeptides, that is, peptides released by some neurones such as the slow-conducting C fibres and the rapid-conducting A-delta fibres. These neurones belong to the category of non-adrenergic non-cholinergic nerves (NANC), which perform their action through a mechanism known as "axonic reflex". This mechanism is an antidromic stimulation which produces a secretion of neuropeptides, especially substance P. It is known that substance P, once released, is able to exert a number of actions including among others inflammatory and bronchospastic activities and a stimulation of the immunologic system. Other effects attributed to this substance are an increase in capillary permeability and oedema and the perpetuation of certain conditions such as asthma, rhinitis and chronic urticaria or hives. The production, metabolism and actions of this neuropeptide are described.


Assuntos
Substância P/fisiologia , Animais , Asma/fisiopatologia , Espasmo Brônquico/fisiopatologia , Capsaicina/farmacologia , Capsaicina/uso terapêutico , Liberação de Histamina , Humanos , Imunidade Celular , Inflamação/fisiopatologia , Mamíferos/fisiologia , Fibras Nervosas/fisiologia , Sistema Nervoso/metabolismo , Sistema Nervoso/fisiopatologia , Neurônios/metabolismo , Substância P/biossíntese , Substância P/imunologia , Urticária/fisiopatologia , Vasodilatação/efeitos dos fármacos
8.
Allergol Immunopathol (Madr) ; 20(3): 119-23, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1384299

RESUMO

Six young healthy volunteers were used as experimental models to study the efficacy of cetirizine 10 mg and terfenadine 60 mg with regard to the onset of action and duration of the peripheral antihistaminic effect (cutaneous activity). For this purpose, 10 micrograms of histamine were used administered as intradermal injection at the internal border of the forearm at times 0', 30', 60', 90', 120', 180', 240', 360', 480' and 24 h after the intake of the drug, with a minimum interval of 7 days between one drug and the other. The inhibition of the cutaneous activity of histamine was assessed by planimetry of the papule transferred to adhesive paper. Both antihistamines were well tolerated by the oral route and our patients did not refer any anticholinergic side effects nor sedation, which are classically described in relation to first generation anti-H1 drugs. When comparing both antihistamines as to their ability to inhibit the response, there are no differences between them at 30', but from this time point up to 24 h cetirizine inhibits significantly more than terfenadine the response to histamine; cetirizine achieves its maximal effect at 180', while terfenadine does so at 240'; both drugs maintain their maximal effect antil 480' and, as was previously mentioned, at these doses cetirizine shows a higher percentage of inhibition than does terfenadine at equal time points.


Assuntos
Cetirizina/farmacologia , Antagonistas dos Receptores Histamínicos H1/farmacologia , Liberação de Histamina/efeitos dos fármacos , Testes Intradérmicos , Terfenadina/farmacologia , Administração Oral , Adulto , Cetirizina/administração & dosagem , Humanos , Terfenadina/administração & dosagem , Fatores de Tempo
9.
Contact Dermatitis ; 38(5): 288, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9667454

RESUMO

PIP: Although allergic reactions to copper are rare, skin disorders may appear or worsen during the perimenstrual period. This paper presents the case of a 41-year-old user of a copper-containing IUD who presented with a history of recurrent, self-healing skin eruption associated with abdominal pain. The eruption followed a cyclical pattern, appearing 3-7 days before menses and improving spontaneously with the onset of bleeding. Patch testing revealed a positive reaction to copper sulfate and nickel sulfate. After the IUD was removed, abdominal symptoms subsided at the next cycle and progressive resolution of the dermatitis was observed.^ieng


Assuntos
Dermatite Alérgica de Contato/etiologia , Dispositivos Intrauterinos de Cobre/efeitos adversos , Menstruação , Adulto , Alérgenos , Cobre/efeitos adversos , Feminino , Humanos
10.
Allergol Immunopathol (Madr) ; 21(2): 84-7, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8337993

RESUMO

The diagnosis of Alternaria allergy is difficult and tests in vivo and in vitro usually do not give results as satisfactory as those obtained with other allergens. We studied 33 patients with a cutaneous response of 2 mm2 or more to skin-prick tests for Alternaria (extract containing 104 micrograms/ml of Alt-1). Results were compared with those of RAST. Skin tests were positive in 75.8% of cases (the resulting papule was the same size as or larger than that elicited by 10 mg/ml histamine) and negative in 24.2% of cases. RAST was positive in 75% of cases and negative in 25%. There was no significant difference in the frequencies. RAST was positive four times more often in males than in females; when these figures were corrected for population data, the ratio was 2:1. The coefficient of correlation between the intensity of skin-test and RAST results was r = 0.51 (p < 0.05). These findings are evaluated and results are discussed.


Assuntos
Alérgenos/efeitos adversos , Alternaria , Teste de Radioalergoadsorção , Rinite Alérgica Perene/etiologia , Testes Cutâneos , Adolescente , Adulto , Asma/diagnóstico , Asma/etiologia , Feminino , Humanos , Masculino , Valor Preditivo dos Testes , Rinite Alérgica Perene/diagnóstico , Sensibilidade e Especificidade
11.
Allergol Immunopathol (Madr) ; 21(1): 3-5, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8328354

RESUMO

Seventy atopic patients were studied. Pin-prick skin tests with cat epithelium extract (Ifidesa-Aríste-gui) were made. The results were compared by dividing the patients into a group with clinical manifestations of contact with cats and a group without clinical manifestations of contact with cats. Our results show that skin tests for cat epithelium, such as those carried out routinely in clinical practice, are not very sensitive or specific, and, therefore, are not suitable for diagnosis or prevalence studies.


Assuntos
Alérgenos , Gatos/imunologia , Epitélio/imunologia , Glicoproteínas , Hipersensibilidade Imediata/diagnóstico , Testes Intradérmicos , Adolescente , Adulto , Idoso , Animais , Criança , Estudos de Avaliação como Assunto , Reações Falso-Negativas , Reações Falso-Positivas , Feminino , Humanos , Hipersensibilidade Imediata/etiologia , Masculino , Pessoa de Meia-Idade , Saliva/imunologia , Sensibilidade e Especificidade
12.
Allergol Immunopathol (Madr) ; 21(1): 15-9, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8328352

RESUMO

We studied 66 patients allergic to mould Alternaria. 53% males and 47% females, with 60% diagnosed as having asthma versus 40% rhinitis, only 29% had allergy to Alternaria without any other cutaneous reactivity while 71% were polisensitized, more frequently to D. pteronyssinus, grass pollen, Cladosporium and cat epithelium. We compared the patients allergic to Alternaria with those allergic to grass pollen and D. pteronyssinus.


Assuntos
Alérgenos/imunologia , Alternaria/imunologia , Hipersensibilidade Respiratória/etiologia , Adolescente , Adulto , Fatores Etários , Animais , Gatos/imunologia , Criança , Cladosporium/imunologia , Feminino , Humanos , Masculino , Ácaros/imunologia , Pólen/imunologia , Distribuição Aleatória , Hipersensibilidade Respiratória/epidemiologia , Hipersensibilidade Respiratória/imunologia , Fatores Sexuais , Esporos Fúngicos
13.
Allergol Immunopathol (Madr) ; 21(4): 158-60, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8237721

RESUMO

A study was made of 55 patients with skin prick test results for Plantago lanceolata of 3 mm2 or more. They were evaluated in relation to the response elicited by 10 mg/ml of histamine HCl. Patients with a response to Plantago less intense than the response to histamine were considered as having a "negative" response, whereas those whose response to Plantago was more intense than the response to histamine were considered as having a "positive" response. In 35 cases a radioallergosorbent test (RAST) was performed and in 22, nasal provocative testing (NPT). The frequency of positive response was 0.63 for skin tests, 0.11 for RAST and 0.72 for NPT. Among the patients with positive NPT, the frequencies of positive response to skin tests and RAST were 0.71 and 0.6 (p < 0.05), respectively. Results are discussed and study methods are proposed.


Assuntos
Hipersensibilidade/diagnóstico , Testes Intradérmicos , Testes de Provocação Nasal , Plantas Comestíveis , Teste de Radioalergoadsorção , Adulto , Estudos de Avaliação como Assunto , Feminino , Humanos , Hipersensibilidade/etiologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
14.
Allergol Immunopathol (Madr) ; 20(5): 207-10, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1363340

RESUMO

An analysis is made of the effectiveness of terfenadine at dosages of 60 and 120 mg, of cetirizine at a dose of 10 mg, and of loratadine and ebastine at a dose of 10 mg in inhibiting the papule induced by 20 mcg of intradermal histamine. Although all produced significant inhibition, cetirizine and terfenadine 120 mg showed a significantly greater inhibition coefficient than loratadine.


Assuntos
Antagonistas dos Receptores Histamínicos H1/farmacologia , Testes Intradérmicos , Adulto , Butirofenonas/administração & dosagem , Butirofenonas/farmacologia , Cetirizina/administração & dosagem , Cetirizina/farmacologia , Relação Dose-Resposta Imunológica , Feminino , Histamina , Antagonistas dos Receptores Histamínicos H1/administração & dosagem , Humanos , Loratadina/administração & dosagem , Loratadina/farmacologia , Masculino , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Distribuição Aleatória , Terfenadina/administração & dosagem , Terfenadina/farmacologia
15.
J Cutan Pathol ; 24(8): 507-10, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9331897

RESUMO

The histopathological changes observed in the cutaneous rash of three patients who suffered the acute phase of HIV infection are described. In all three patients a perivascular and interstitial inflammatory infiltrate was present in the upper and mid-reticular dermis. In one biopsy isolated areas of epidermal necrosis were observed and in the two other biopsies a perifollicular inflammatory infiltrate was detected with perforation in one case. Furthermore, a periductal infiltrate was observed in one of these biopsies.


Assuntos
Exantema/patologia , Infecções por HIV/patologia , Úlceras Orais/patologia , Adulto , Exantema/complicações , Infecções por HIV/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Úlceras Orais/complicações
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