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1.
Arch Environ Contam Toxicol ; 53(3): 321-8, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17728989

RESUMO

The toxicity of leather tanning wastewater from a traditional tannery (TT), which is based on vegetable tannin (VT), was compared with wastewater from a tannery combining the use of chromium-based tanning (CT) with VT-based tanning operations. Wastewater samples from a TT and a CT plant as well as from five sewer sampling points were collected in Marrakesh, Morocco, and the concentrations of VT and some selected inorganics were measured. A set of bioassays were used to test wastewater toxicity in sea urchin (Paracentrotus lividus) embryos and sperm, in Daphnia magna, and in marine microalgae (Dunaliella tertiolecta). Toxicity end points included: (1) developmental defects, embryonic mortality, sperm fertilization success, and offspring damage in sea urchins; (2) D. magna immobilization; and (3) algal growth rate inhibition. Toxicity tests on TT and CT effluents (TTE and CTE) were run at dilutions ranging from 0.1% to 2% (sea urchins and algae) or up to 12% in D. magna. Parallel bioassays were run on VT extract (VTE) at nominal tannin concentrations ranging from 0.1 to 10 mg l(-1). The results showed higher toxicity of CTE compared with TTE. CTE toxicity in sea urchins and algae showed concentration-related trends, whereas TTE exerted hormetic effects at levels of 0.1% to 0.2% and toxic effects at levels >or=1%. The same trends were observed for VTE, suggesting a prevailing role of tannin in TTE-associated effects. The moderate wastewater toxicity of VT-based tanneries might prompt interest in the VT tanning process.


Assuntos
Cromo/toxicidade , Curtume , Taninos/toxicidade , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/toxicidade , Animais , Bioensaio , Daphnia/efeitos dos fármacos , Daphnia/fisiologia , Embrião não Mamífero/efeitos dos fármacos , Eucariotos/efeitos dos fármacos , Eucariotos/crescimento & desenvolvimento , Feminino , Masculino , Ouriços-do-Mar/embriologia
2.
Arch Environ Contam Toxicol ; 46(3): 336-44, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15195805

RESUMO

Tannin from mimosa trees (Acacia sp.) utilized in traditional leather tanning was tested for toxicity in sea urchin (Sphaerechinus granularis and Paracentrotus lividus) embryos and sperm, marine, and freshwater algae (Selenastrum capricornutum and Dunaliella tertiolecta), and Daphnia magna. Based on a two-step tanning procedure used in traditional tanneries, two mimosa tannin preparations, i.e., fresh tannin (FT) and used tannin (UT), were tested as suspensions. The early results in S. granularis embryos showed that UT exerted lower acute toxicity than FT, namely, 1 vs 100 mg/L, to obtain 100% mortality, respectively. Subsequent bioassays were conducted on fresh tannin water extracts (TWE) corresponding to nominal tannin concentrations ranging from 0.1 to 30 mg/L. Developmental toxicity, up to embryonic mortality was exerted by TWE at levels > 1 mg/L, S. granularis being more sensitive than P. lividus embryos/larvae. At the concentration of 0.1 mg/L, the frequencies of larval malformations were significantly lower than in controls. This positive stimulatory effect (currently termed as hormesis) was observed in extended numbers of culture replicates (up to 14) and was significant in the embryo cultures characterized by a relatively poor control quality (with < 70% viable larvae in controls), whereas this effect was not observed in good-quality cultures (with > or = 70% viable larvae in controls). Cytogenetic analysis of S. granularis embryos reared in FT or UT suspensions (1 mg/L to 1 g/L) showed mitotoxic effects (decrease in active mitoses per embryo) in FT-exposed, but not in UT-exposed embryos. Mitotic aberrations were significantly increased by 10 mg/L UT. Sperm fertilization success in both sea urchin species showed an increasing fertilization rate (FR) up to 0.3 mg/L TWE and a dose-related decrease in FR up to 30 mg/L. Again, the offspring of P. lividus sperm exposed to TWE (0.1 and 0.3 mg/L) showed a decrease in larval malformations compared to controls, whereas a dose-related increase in developmental defects was observed in the offspring of P. lividus sperm exposed to higher TWE levels (1 to 30 mg/L). Algal cell growth bioassays in two species (S. capricornutum and D. tertiolecta) also showed a maximum growth at TWE levels ranging from 0.3 to 3 mg/L and a subsequent decline up to 30 mg/L TWE. D. magna bioassays resulted in daphnid immobilization by TWE concentrations ranging from 100 to 300 mg/L. The results demonstrate that tannins utilized in traditional leather tanning industry may raise concern of environmental damage at relatively high concentrations, whereas low-level tannins may result in hormetic effects. The present study also points to the need for bioassay design that should rely on adequate criteria in control quality, allowing to detect both inhibitory and hormetic effects.


Assuntos
Acacia/química , Taninos/toxicidade , Animais , Bioensaio/métodos , Clorófitas/genética , Clorófitas/crescimento & desenvolvimento , Anormalidades Congênitas/veterinária , Daphnia/embriologia , Daphnia/genética , Daphnia/crescimento & desenvolvimento , Fertilização/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Controle de Qualidade , Reprodutibilidade dos Testes , Ouriços-do-Mar/embriologia , Ouriços-do-Mar/genética , Ouriços-do-Mar/crescimento & desenvolvimento
3.
Ann Ital Chir ; 75(5): 599-601, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15960352

RESUMO

In this report we define the terms of saccular, extra-saccular and intrasaccular tumor and present a rare case of intrasaccular tumor of the colon; it is remarked a careful clinical examination of patients with inguinal hernias to find a colon tumor; diagnosis in emergency is intra-operative. Two therapeutics options are possible: the simultaneous treatment or the delayed resolution.


Assuntos
Adenocarcinoma/complicações , Hérnia Inguinal/etiologia , Neoplasias do Colo Sigmoide/complicações , Adenocarcinoma/cirurgia , Idoso , Humanos , Masculino , Neoplasias do Colo Sigmoide/cirurgia
4.
Ann Ital Chir ; 75(6): 701-3, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15960368

RESUMO

We present a case report of a patient affected by chronic ileitis re-made acute and in which we found some entheroliths; they wern't not bezoars. We remarked the importance in bowel diseases in which are stasis or ipomotility like the Crohns disease. Sometimes they are responsible of subsequent complications like obstructions, hemorrages, perforations and so their presence must be considered by important diagnostic implications.


Assuntos
Cálculos/diagnóstico , Doenças do Íleo/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade
5.
Ann Ital Chir ; 74(3): 343-7, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-14677292

RESUMO

SEP is an increasingly seen complication of CAPD; we have the occasion to see again this condition because two patients came under our observation. We have remarked the unknown etiology and pathogenesis, the difficult diagnosis and therapy, and the often poor prognosis.


Assuntos
Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/etiologia , Idoso , Candidíase/complicações , Comorbidade , Diagnóstico Diferencial , Enterococcus faecalis , Evolução Fatal , Feminino , Fibrose , Humanos , Falência Renal Crônica/terapia , Masculino , Peritonite/diagnóstico , Peritonite/patologia , Peritonite/cirurgia , Infecções por Pseudomonas/complicações , Esclerose , Infecções Estreptocócicas/complicações
6.
Ann Ital Chir ; 74(5): 579-82, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-15139716

RESUMO

MMPB is a rare disease, very often is a casual finding because has not a specific sintomatology; the isthological examen permits the diagnosis; the prognosis is good but follow-up is necessary because the recurrences are possible.


Assuntos
Mesotelioma Cístico , Neoplasias Peritoneais , Feminino , Seguimentos , Humanos , Mesotelioma Cístico/diagnóstico , Mesotelioma Cístico/patologia , Mesotelioma Cístico/cirurgia , Pessoa de Meia-Idade , Neoplasias Peritoneais/diagnóstico , Neoplasias Peritoneais/patologia , Neoplasias Peritoneais/cirurgia , Peritônio/patologia , Fatores de Tempo
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