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1.
Artigo em Inglês | MEDLINE | ID: mdl-37712443

RESUMO

Summary: Background. LTP allergy is often a challenge for clinicians. We evaluated a multiplex diagnostic approach with diverse cofactors to stratify LTP syndrome risk. Methods. Of the 1,831 participants screened with 'Allergy Explorer-ALEX-2', 426 had reactions to at least one LTP. Data was gathered and recorded via an electronic database. Results. Reactivity to peach Pru p 3 was found in 77% of individuals with LTP allergy. Higher levels of specific IgE and concurrent sensitization to more than 5 molecules (50% of all LTP-sensitised participants, 62% of symptomatic cases) were significantly associated with an increased risk of severe reactions (p = 0.001). Several cofactors, either alone or in combination, also influenced patients' clinical outcomes. Some cofactors increased the risk of severe reactions, such as mono reactivity to LTP in 44.6% of cases (p = 0.001), FDEIA in 10.8% of patients (p = 0.001), and FDNIH in 11.5% (p = 0.005). On the other hand, reactivity to PR10 (24.2%; p = 0.001), profilin hypersensitivity (10.3%; p = 0.001), and/or atopic dermatitis (16.7%; p = 0.001) had a mitigating effect on symptom severity. Conclusions. Clinical severity of LTP syndrome is associated with an expanded IgE repertoire in terms of the number of LTP components recognized and increased IgE levels in individual molecules. Ara h 9, Cor a 8, and Mal d 3 showed the strongest association with clinical severity. In addition, several cofactors may either exacerbate (FDEIA, FDHIH, and LTP monoreactivity) or ameliorate (atopic dermatitis and co-sensitization to profilin and/or PR10) individual patient outcomes. These factors may be utilized for the daily clinical management of LTP syndrome.

2.
Eur Ann Allergy Clin Immunol ; 50(4): 148-155, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29479929

RESUMO

Summary: The families of seed storage proteins, together with profilins, oil-bodies-associated oleosins, and pathogenesis-related (PR) proteins like PR-10 (Bet v 1-like), PR-12 (defensins) and PR-14 (non-specific lipid transfer protein), are the main causes of IgE sensitization to tree nuts, legumes and seeds. All these allergens, with the exclusion of profilins and of PR-10, are heat-stable and possibly responsible for fatal or almost fatal adverse reactions to such foods. In this short review, we will discuss the relationship and amino acid identities among some of the seed storage homologue molecules identified to date from tree nuts, seeds and legumes.


Assuntos
Alérgenos/genética , Antígenos de Plantas/genética , Hipersensibilidade a Noz/imunologia , Proteínas de Armazenamento de Sementes/genética , Homologia de Sequência de Aminoácidos , Alérgenos/imunologia , Antígenos de Plantas/imunologia , Fabaceae/imunologia , Humanos , Imunoglobulina E/imunologia , Nozes/imunologia , Proteínas de Armazenamento de Sementes/imunologia , Sementes/imunologia
3.
Eur Ann Allergy Clin Immunol ; 50(5): 217-225, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30039692

RESUMO

Summary: Background. The development of recombinant technology supported the allergy diagnostic work-up in the daily clinical practice, representing a useful tool for epidemiological studies. Methods. An atlas of the IgE sensitization profiles found throughout Italy was prepared from a nationwide, multicenter, cross-sectional study. Results. 6052 unselected consecutive individuals, belonging to North-West [NW], North-East [NE], Centre [C], South [S], and Islands subset [Is] were evaluated by means of the ImmunoCAP ISAC test. The top-ranked sensitizations found were Cup a 1 in [C] (58.1%) and [S] (53.6%), Phl p 1 in the North (from 46.1% to 49%), and Cyn d 1 in [Is] (44.2%). High frequency of house dust mite group 2 molecules sensitization was found in [C] (36.9%) and [S] Italy (40.8%), whilst low level of reactivity was recorded in [NW] (20%). Pellitory hypersensitivity was mainly found in [C], [S], and [Is], whilst ragweed Amb a 1 sensitivity was particularly found in [NW] Italy. IgE recognition of PR-10, Profilin, and nsLTP was mutually exclusive in 69.1% of cases, PR-10 reactivity mostly occurring in [NE], Profilin in [NW], and nsLTP molecules recognition mainly recorded in [C] and [S]. Conclusions. Divergent IgE sensitization patterns were found along Italy, possibly linked to the distinct geographical locations, indicating multiplex system IgE analysis as a reliable approach for epidemiological evaluation even in small geographical areas.


Assuntos
Hipersensibilidade/epidemiologia , Imunização/estatística & dados numéricos , Imunoglobulina E/metabolismo , Adolescente , Adulto , Alérgenos/genética , Alérgenos/imunologia , Estudos Transversais , Testes Diagnósticos de Rotina , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Adulto Jovem
4.
Allergy ; 72(4): 671-674, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28042669

RESUMO

Nine hundred and thirty-nine rPla a 1, nPla a 2, and rPla a 3 ImmunoCAP ISAC reactors were studied. nPla a 2pos MUXF3pos but Pla a 1/2neg subjects were excluded from the study because they were cross-reactive carbohydrate determinant reactors. Among the 764 remaining participants, 71.9% were Pla a 3pos , 54.1% Pla a 2pos , and 10.9% Pla a 1pos . Among Pla a 3 reactors, 89.6% were Pru p 3pos and 86.8% Jug 3pos , but the strongest IgE recognition relationship was observed between Pla a 3 and Jug r 3. Distinctive clinical subsets could be documented among plane tree-allergic patients. Pla a 3 reactors had both local and systemic food-induced reactions, but lower past respiratory symptoms occurrence. Pla a 2 reactivity was associated with respiratory symptoms but inversely related to systemic reactions to food. Cosensitization to Pla a 2 and Pla a 3 was associated with a lower past incidence of severe food-induced reactions.


Assuntos
Alérgenos/imunologia , Antígenos de Plantas/imunologia , Hipersensibilidade Alimentar/diagnóstico , Hipersensibilidade/diagnóstico , Hipersensibilidade/imunologia , Traqueófitas/efeitos adversos , Árvores , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Diagnóstico Diferencial , Feminino , Humanos , Imunoglobulina E/imunologia , Lactente , Masculino , Pessoa de Meia-Idade , Razão de Chances , Avaliação de Sintomas , Adulto Jovem
5.
J Chem Phys ; 146(15): 155102, 2017 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-28433029

RESUMO

The self-assembly process of clathrin coated pits during endocytosis has been simulated by combining and extending coarse grained models of the clathrin triskelion, the adaptor protein AP2, and a flexible network membrane. The AP2's core, upon binding to membrane and cargo, releases a motif that can bind clathrin. In conditions where the core-membrane-cargo binding is weak, the binding of this motif to clathrin can result in a stable complex. We characterize the conditions and mechanisms resulting in the formation of clathrin lattices that curve the membrane, i.e., clathrin coated pits. The mechanical properties of the AP2 ß linker appear crucial to the orientation of the curved clathrin lattice relative to the membrane, with wild-type short linkers giving rise to the inward curving buds enabling endocytosis while long linkers produce upside-down cages and outward curving bulges.


Assuntos
Clatrina/química , Modelos Químicos , Membranas/química , Simulação de Dinâmica Molecular , Tamanho da Partícula , Agregados Proteicos , Conformação Proteica
6.
Allergy ; 70(8): 933-43, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25903791

RESUMO

BACKGROUND: Nonspecific lipid transfer proteins (nsLTPs) represent a major cause of systemic food allergic reactions in the Mediterranean area. This study investigate hierarchical patterns and cluster relationships of IgE sensitization to different nsLTPs, and the relationship to clinical allergy in a large Italian cohort. METHODS: A total of 568 nsLTP-positive subjects after IgE ImmunoCAP-ISAC microarray analysis with Ara h 9, Art v 3, Cor a 8, Jug r 3, Pla a 3, Pru p 3 and Tri a 14 allergens were studied. IgE inhibition experiments were carried out with mugwort and plane tree pollen extracts. RESULTS: Eighty-two per cent of nsLTP-positive participants (94% if <6 years old) were Pru p 3(pos) , and 71% were Jug r 3(pos) . Participants who reacted to >5 nsLTPs reported a higher incidence of food-induced systemic reactions. Only Art v 3 and Pla a 3 (mugwort and plane tree nsLTPs, respectively) were associated with respiratory symptoms, and a correlation was observed between sensitization to pollen and plant food nsLTPs, particularly between Pla a 3 and tree nut/peanut nsLTPs. Co-sensitization to Par j 2 and PR-10 or profilin pan-allergens was associated with a lower prior prevalence of severe food-induced reactions. In inhibition assays, plane and mugwort pollen extracts inhibited 50-100% of IgE binding to food nsLTPs in microarrays. CONCLUSIONS: Testing IgE reactivity to a panel of nsLTP allergens unveils important associations between nsLTP sensitization profiles and clinical presentation and allows the identification of novel cluster patterns indicating likely cross-reactivities and highlighting potential allergens for nsLTP immunotherapy.


Assuntos
Proteínas de Transporte/imunologia , Hipersensibilidade Alimentar/imunologia , Hipersensibilidade Alimentar/terapia , Imunização/métodos , Adolescente , Adulto , Idoso , Alérgenos/imunologia , Criança , Pré-Escolar , Análise por Conglomerados , Estudos de Coortes , Feminino , Hipersensibilidade Alimentar/fisiopatologia , Humanos , Hipersensibilidade/epidemiologia , Hipersensibilidade/imunologia , Hipersensibilidade/terapia , Imunoglobulina E/imunologia , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Pólen/imunologia , Prevalência , Medição de Risco , Índice de Gravidade de Doença , Adulto Jovem
7.
Clin Genet ; 86(3): 252-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24033287

RESUMO

The mode of inheritance of Alport syndrome (ATS) has long been controversial. In 1927, the disease was hypothesized as a dominant condition in which males were more severely affected than females. In 1990, it was considered an X-linked (XL) semidominant condition, due to COL4A5 mutations. Later on, a rare autosomal recessive (AR) form due to COL4A3/COL4A4 mutations was identified. An autosomal dominant (AD) form was testified more recently by the description of some large pedigrees but the real existence of this form is still questioned by many and its exact prevalence is unknown. The introduction of next generation sequencing (NGS) allowed us to perform an unbiased simultaneous COL4A3-COL4A4-COL4A5 analysis in 87 Italian families (273 individuals) with clinical suspicion of ATS. In 48 of them (55%), a mutation in one of the three genes was identified: the inheritance was XL semidominant in 65%, recessive in 4% and most interestingly AD in 31% (15 families). The AD form must therefore be seriously taken into account in all pedigrees with affected individuals in each generation. Furthermore, a high frequency of mutations (>50%) was shown in patients with only 1 or 2 clinical criteria, suggesting NGS as first-level analysis in cases with a clinical suspicion of ATS.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Padrões de Herança/genética , Nefrite Hereditária/genética , Sequência de Bases , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Itália , Masculino , Dados de Sequência Molecular , Mutação/genética , Linhagem
9.
Eur Rev Med Pharmacol Sci ; 27(2): 799-804, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36734722

RESUMO

OBJECTIVE: To assess the feasibility of a new device for telemonitoring vital parameters during iloprost infusion. MATERIALS AND METHODS: In a pilot study, patients with systemic sclerosis received iloprost infusion while being telemonitored with Umana T1 Heart Monitor, within the hospital, under the supervision of family/community nurses and rheumatologists. Patients were administered a questionnaire to obtain information on satisfaction, practicability, and compliance with the new monitoring device. RESULTS: Data recorded by the device for blood pressure, heart rate, and oximetry were concordant with those registered directly by nurses. Most patients found the device useful and thought it could be used at home, even while working. CONCLUSIONS: Umana Heart Monitor T1 could be a valuable aid in at-home iloprost therapy in patients with systemic sclerosis.


Assuntos
Iloprosta , Escleroderma Sistêmico , Humanos , Iloprosta/uso terapêutico , Projetos Piloto , Estudos de Viabilidade , Escleroderma Sistêmico/tratamento farmacológico , Pressão Sanguínea , Vasodilatadores/uso terapêutico
10.
Mar Pollut Bull ; 185(Pt A): 114181, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36308819

RESUMO

Assessing the status of marine pollution at regional and sub-regional scales requires the use of comparable and harmonized data provided by multiple institutions, located in several countries. Standardized data management and quality control are crucial for supporting a coherent evaluation of marine pollution. Taking the Eastern Mediterranean Sea as a case study, we propose an approach to improve the quality control procedures used for sediment pollution data, thus supporting a harmonized environmental assessment. The regional ranges of contaminant concentrations in sediments were identified based on an in-depth literature review, and the lowest measured concentrations were evaluated to determine the "background concentrations" of chemical substances not yet targeted in the Mediterranean Sea. In addition, to verify the suitability of the approach for validating large data collections provided by multiple sources, the determined ranges were used to validate a regional dataset available through EMODnet data infrastructure.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Oligoelementos , Poluentes Químicos da Água , Hidrocarbonetos Policíclicos Aromáticos/análise , Sedimentos Geológicos/química , Monitoramento Ambiental/métodos , Poluentes Químicos da Água/análise , Coleta de Dados , Controle de Qualidade
11.
Pharmaceutics ; 13(9)2021 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-34575597

RESUMO

Lyso-7 is a novel synthetic thiazolidinedione, which is a receptor (pan) agonist of PPAR α,ß/δ,γ with anti-inflammatory activity. We investigated the cardiotoxicity of free Lyso-7 in vitro (4.5-450 nM), and Lyso-7 loaded in polylactic acid nanocapsules (NC) in vivo (Lyso-7-NC, 1.6 mg/kg). In previous work, we characterized Lyso-7-NC. We administered intravenously Lyso-7, Lyso-7-NC, control, and blank-NC once a day for seven days in mice. We assessed cell contraction and intracellular Ca2+ transients on single mice cardiomyocytes enzymatically isolated. Lyso-7 reduced cell contraction and accelerated relaxation while lowering diastolic Ca2+ and reducing Ca2+ transient amplitude. Lyso-7 also promoted abnormal ectopic diastolic Ca2+ events, which isoproterenol dramatically enhanced. Incorporation of Lyso-7 in NC attenuated drug effects on cell contraction and prevented its impact on relaxation, diastolic Ca2+, Ca2+ transient amplitude, Ca2+ transient decay kinetics, and promotion of diastolic Ca2+ events. Acute effects of Lyso-7 on cardiomyocytes in vitro at high concentrations (450 nM) were globally similar to those observed after repeated administration in vivo. In conclusion, we show evidence for off-target effects of Lyso-7, seen during acute exposure of cardiomyocytes to high concentrations and after repeated treatment in mice. Nano-encapsulation of Lyso-7 in polymeric NC attenuated the unwanted effects, particularly ectopic Ca2+ events known to support life-threatening arrhythmias favored by stress or exercise.

12.
Int J Immunopathol Pharmacol ; 23(4): 1287-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21244781

RESUMO

Nonspecific lipid transfer proteins (nsLTPs) are members of the prolamine superfamily and they are found in pollen and food, as well as in latex. Due to the strong stability both against pepsin digestion and thermal denaturation, sensitisation towards these proteins is often associated with severe systemic reactions (angioedema, urticaria, asthma, anaphylaxis, etc.) following the ingestion of both raw or fresh food and cooked or preserved food. Many studies have shown reactivity towards nsLTPs both via inhalation and orally and in this study we present two cases of nsLTPs-sensitive patients who manifested the immediate onset of skin reactions following the use of cosmetic products containing these proteins. Thus, in order to prevent immediate reactions linked to their use, it is necessary to recommend nsLTPssensitive patients to avoid the topical use of products containing these proteins (and obviously the ingestion of foods containing these proteins).


Assuntos
Proteínas de Transporte/imunologia , Cosméticos/efeitos adversos , Hipersensibilidade/etiologia , Pele/imunologia , Adulto , Feminino , Humanos , Testes Cutâneos
13.
Mater Sci Eng C Mater Biol Appl ; 94: 220-233, 2019 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-30423704

RESUMO

For best photosensitizer activity phthalocyanine dyes used in photodynamic therapy should be molecularly dispersed. Polyethylene glycol-block-polylactide derivatives presenting benzyl side-groups were synthesized to encapsulate a highly lipophilic phthalocyanine dye (AlClPc) and evaluate the effect of π-π interactions on the nanocarrier colloidal stability and dye dispersion. Copolymers with 0, 1, 2 and 6 mol% of benzyl glycidyl ether (BGE) were obtained via polyethylene glycol initiated ring-opening copolymerization of D,l-lactide with BGE. The block copolymers formed stable, monodisperse nanospheres with low in vitro cytotoxicity. AlClPc loading increased the nanosphere size and affected their colloidal stability. The photo-physical properties of the encapsulated dye, studied in batch and after separation by field flow fractionation, demonstrated the superiority of plain PEG-PLA over BGE-containing copolymers in maintaining the dye in its monomeric (non-aggregated) form in aqueous suspension. High dye encapsulation and sustained dye release suggest that these nanocarriers are good candidates for photodynamic therapy.


Assuntos
Portadores de Fármacos/química , Indóis/farmacologia , Nanosferas/química , Fármacos Fotossensibilizantes/farmacologia , Poliésteres/química , Polietilenoglicóis/química , Animais , Morte Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Indóis/química , Isoindóis , Cinética , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Peso Molecular , Octanóis/química , Tamanho da Partícula , Fármacos Fotossensibilizantes/química , Poliésteres/síntese química , Polietilenoglicóis/síntese química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Eletricidade Estática , Células Vero
14.
Allergy ; 63(7): 891-6, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18588555

RESUMO

BACKGROUND: The clinical relevance of immunoglobulin E (IgE) to plant glycans is a longstanding debate. We sought to evaluate their clinical reactivity using the human glycoprotein lactoferrin expressed in rice. METHODS: Allergic patients with IgE antibodies against plant glycans were analyzed for the presence of IgE against rice-produced lactoferrin. The potency of IgE to induce mediator release was assessed by basophil histamine release and skin prick tests (SPTs). Clinical relevance was evaluated by double-blind placebo-controlled oral challenge (DBPCOC). RESULTS: Twenty-four of 29 sera (82.7%) with IgE antibodies against plant glycans demonstrated IgE binding to transgenic lactoferrin. In three of five cases transgenic lactoferrin induced histamine release. Compared to a control major grass pollen allergen lactoferrin concentrations needed for biological activity of IgE were 5-6 orders of magnitude higher. Skin prick test and DBPCOC were negative in five patients with potential clinical reactivity that volunteered to undergo these in vivo challenges. CONCLUSIONS: Poor or no biological activity and lack of clinical relevance of IgE-binding plant glycans (five out of five) was demonstrated using human lactoferrin expressed in rice as a model.


Assuntos
Alérgenos/imunologia , Imunoglobulina E/imunologia , Polissacarídeos/imunologia , Adolescente , Teste de Degranulação de Basófilos , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Criança , Método Duplo-Cego , Feminino , Liberação de Histamina , Humanos , Hipersensibilidade/imunologia , Imunoglobulina E/sangue , Lactoferrina , Masculino , Pessoa de Meia-Idade , Oryza/genética , Phleum/imunologia , Proteínas de Plantas/imunologia , Plantas Geneticamente Modificadas/genética , Pólen/imunologia , Teste de Radioalergoadsorção , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Testes Cutâneos
15.
Food Chem Toxicol ; 45(6): 1065-75, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17306916

RESUMO

Total polychlorinated biphenyl (SigmaPCB) concentrations calculated as the sum of 21 and the toxicity equivalent (TEQ) of dioxin-like PCBs calculated on the basis of the toxic equivalent factors were assessed in Manila clams Tapes philippinarum cultured in the Venice Lagoon. The concentrations showed a predominance of hexa-chlorobiphenyls followed by penta-, hepta-, tetra- and tri-chlorobiphenyls. The highest levels of SigmaPCB detected were 4.01 ng/g, 2.71 ng/g and 2.68 ng/g wet weight at a southern lagoon site and two northern lagoon sites, respectively. There was a significant differentiation in toxicity levels between culture sites. The highest value was 0.239 pg TEQ/g at a southern lagoon site; the lowest was 0.004 pg TEQ/g at a central lagoon site.


Assuntos
Bivalves/química , Contaminação de Alimentos/análise , Bifenilos Policlorados/análise , Animais , Cromatografia Gasosa-Espectrometria de Massas , Itália , Lipídeos/análise , Reprodutibilidade dos Testes
16.
Mar Pollut Bull ; 55(10-12): 425-35, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18023822

RESUMO

The release of tributyltin (TBT) from maritime traffic represents one of the main problems of direct, diffuse, and continued contamination of the marine environment. In the present survey, the concentrations of TBT and dibultytin (DBT) in brackish waters, sediments, and the gastropods Nassarius nitidus were evaluated in order to estimate the contamination of the southern part of the Venice lagoon. TBT and DBT were determined by GC-MS/MS. Recent contamination of TBT was found in brackish waters near marinas, whereas the highest concentrations of TBT and DBT were observed in surface sediments at dockyards and harbours. High content of organotin in the gastropods sampled near the dockyards, harbours, and marinas showed a mobilisation from the sediments through the food web. The present study allowed assessment of whether, despite the ban on the use of TBT paints, waters, sediments, and biota were still being contaminated by organotin compounds in the southern Venice lagoon.


Assuntos
Monitoramento Ambiental , Compostos Orgânicos de Estanho/análise , Compostos de Trialquitina/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental/métodos , Cromatografia Gasosa-Espectrometria de Massas , Gastrópodes/química , Sedimentos Geológicos/análise , Itália , Água do Mar/análise
17.
Mar Pollut Bull ; 114(2): 1088-1095, 2017 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-27745738

RESUMO

A high concentration of hydrocarbons in the environment is indicative of pollution. To evaluate the effect of hydrocarbons transported by urban runoff, the present study analyzed total petroleum hydrocarbons (TPHs), aliphatic hydrocarbons (AHs), unresolved complex mixture (UCM), and n-alkanes of the sediments of the canal that cross the urban area of Pelotas, Rio Grande do Sul, Brazil. The carbon preference index (CPI), terrigenous/aquatic ratio (TAR), and pristane/phytane ratio were determined. The TPH content ranged from 177,043.7µg·kg-1±13.4% to 5,892,667.0µg·kg-1±5.9%. The total aliphatic content ranged from 116,268.8µg·kg-1±11.1% to 2,393,592.6µg·kg-1±7.7%, indicating chronic contamination of n-alkanes petrogenic and biogenic sources. The levels of hydrocarbons (TPH, AHs, and n-alkanes) were considered relatively high, confirming the effect of urban runoff on the drainage system of cities and their consequent effect on the estuarine region of Patos Lagoon and other water resources.


Assuntos
Sedimentos Geológicos/análise , Hidrocarbonetos/análise , Poluentes Químicos da Água/análise , Alcanos/análise , Brasil , Cidades , Meio Ambiente , Monitoramento Ambiental , Sedimentos Geológicos/química , Poluição por Petróleo/análise , Poluentes Químicos da Água/química
18.
Sci Total Environ ; 368(1): 298-305, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16376970

RESUMO

The southern basin of the Venice Lagoon has been the focus of fewer studies concerning contamination from heavy metals than the northern and central basins. A recent increase in urban waste waters from Chioggia town, as well as dockyards, shipping and fishing activities, affect this part of the lagoon. The aim of this study was to investigate the total mercury (THg) incidence in sediments and Nassarius reticulatus gastropods in order to assess its distribution and evaluate the level of contamination. THg concentration measured in bottom sediments ranged between 0.1 and 3.4 mg/kg d. wt. The enrichment factor (EF) showed high values (avg. 30, max 49) near the dockyards of Chioggia; the lowest (avg. 9, max 17) were found in the coastal marine sediments near the port entrance of the southern basin. THg in marine scavenger gastropods accumulated in N. reticulatus with concentrations falling within the range of 0.3-1.3 mg/kg d. wt. A positive correlation was found between THg concentration in sediments and in N. reticulatus in all sites, excluding the dockyards. A first local cause for mercury pollution might be attributed to the antifouling paints used in great quantity in the recent past near the town of Chioggia. Moreover, fine suspended sediments associated with tidal flushing are suggested as possibly being the vehicle for pollutant dispersal from the Marghera industrial area to the whole of Venice's lagoon.


Assuntos
Gastrópodes/química , Sedimentos Geológicos/análise , Mercúrio/análise , Poluentes Químicos da Água/análise , Animais , Monitoramento Ambiental , Itália
19.
Sci Total Environ ; 353(1-3): 350-9, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16223521

RESUMO

The chemical and biological properties of the water column at a Tyrrhenian site (Isola del Giglio) were studied during a 3-year period. The results highlighted the oligotrophic features of the site, characterised by quite low concentrations of organic carbon (on average DOC 102 micromol/L and POC 9 micromol/L). Relevant bacterial biomass (on average 42.1 microg C/L) and a notable activity (in terms of frequency of dividing cells, on average more than 5%) were observed. However, remarkable changes for these parameters were seasonally recorded. The cyclic occurrence, generally during the late spring-summer period, of benthic mucilage indicated that localised distrophic processes may occur. In particular, the benthic mucilage events of 2000 and 2001 were investigated, although some comparative information was available also for 1999 and 2002. The mucilage aggregates generally showed high bacterial colonisation, which have remarkable effects on the organic matter cycle both inside the aggregates and in the surrounding seawater. During the benthic mucilage development, an increase of DOC and POC concentrations was observed (up to 129 and 18 micromol/L, respectively, in June 2000 and up to 145 and 10 micromol/L, respectively, in May and June 2001) in the water column adjacent to the bottom. However, a general decrease of the trophic value of particulate matter (in terms of C/N ratio) was also observed, especially in 2000 after the disappearance of the mucilage. The available energy and organic matter during the mucilage events led to an increased presence of bacteria in the bottom waters of the Isola del Giglio, with maximum biomass values in 2001. Similarly, the replicative activity of bacteria was higher in 2001 (frequency of dividing cells about 5% vs. 3% of 2000). The lower activity of 2000, in addition to the lower trophic value of organic matter and different environmental conditions (namely lower temperature), might be involved in the persistence of mucilage in 2000 with respect to the rapid disappearance observed in 2001.


Assuntos
Bactérias/crescimento & desenvolvimento , Carbono/análise , Eucariotos/crescimento & desenvolvimento , Biologia Marinha/estatística & dados numéricos , Fitoplâncton/crescimento & desenvolvimento , Água do Mar/química , Água do Mar/microbiologia , Biomassa , Mar Mediterrâneo , Nitrogênio/análise , Dinâmica Populacional , Estações do Ano
20.
Sci Total Environ ; 353(1-3): 189-203, 2005 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-16225908

RESUMO

We tested the hypothesis that the appearance of mucilage in the Northern Adriatic Sea was related with the accumulation of dissolved organic compounds released by intensive enzymatic activities and not utilized as direct substrate for microbial growth. To do this enzymatic activities and dissolved organic and inorganic pools in periods characterized by the presence of mucilage and in the same seasons but in absence of mucilage were compared. Extracellular enzymatic activities (aminopeptidase, beta-glucosidase and alkaline phosphatase), nutrient pool concentrations (total dissolved nitrogen, dissolved organic nitrogen, total dissolved phosphorus, dissolved organic phosphorus) and the biochemical composition of particulate and dissolved organic matter (in terms of proteins and carbohydrates) were determined on a monthly basis over a period of 3 years. Aminopeptidase and alkaline phosphatase activities displayed higher values in springs preceding the appearance of mucilage than in spring when no mucilage was observed. Beta-Glucosidase activity showed significantly higher values in summer periods characterized by the massive production of mucilage than in summers without mucilage events. The months preceding mucilage events were also characterized by an increase of the alkaline phosphatase to aminopeptidase activity ratio and by a significant accumulation of dissolved proteins. These findings, together with the significant increase of the DON/DOP ratio, suggest that mucilage formation is favoured by the deficiency of organic P. The present study provides compelling evidences that mucilage formation is favoured by the unbalance between organic matter mobilization by enzymatic activities and the accumulation of labile dissolved organic-N compounds.


Assuntos
Eucariotos/enzimologia , Eucariotos/crescimento & desenvolvimento , Biologia Marinha/estatística & dados numéricos , Fitoplâncton/enzimologia , Fitoplâncton/crescimento & desenvolvimento , Água do Mar/química , Fosfatase Alcalina/metabolismo , Aminopeptidases/metabolismo , Mar Mediterrâneo , Nitrogênio/análise , Fósforo/análise , Dinâmica Populacional , Estações do Ano , Espectrofotometria , beta-Glucosidase/metabolismo
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