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1.
J Dairy Sci ; 104(5): 6194-6199, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33685689

RESUMO

Paratuberculosis is a chronic enteric disease affecting virtually all ruminants, but only anecdotal information is currently available about the occurrence of this disease in water buffaloes (Bubalus bubalis). We carried out a survey study aimed at determining the prevalence of paratuberculosis in 2 provinces in the region of Campania, Italy, where about half of all Italian buffaloes are reared. From May 2017 to December 2018, we collected 201,175 individual serum samples from 995 buffalo herds. The sera were collected from animals over 24 mo old and were tested using a commercial ELISA test. The herd-level apparent prevalence result was 54.7%, and the animal-level apparent prevalence was 1.8%. The herd-level true prevalence was estimated using a Bayesian approach, demonstrating a high herd-level prevalence of paratuberculosis in water buffaloes from the Campania area. These findings suggest that the urgent adoption of paratuberculosis herd-control programs for water buffaloes in this area would be beneficial.


Assuntos
Doenças dos Bovinos , Paratuberculose , Animais , Teorema de Bayes , Búfalos , Bovinos , Ensaio de Imunoadsorção Enzimática/veterinária , Itália/epidemiologia , Paratuberculose/epidemiologia , Prevalência , Estudos Soroepidemiológicos
2.
Transbound Emerg Dis ; 65(4): 1033-1038, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29473322

RESUMO

Wild dabbling ducks are the main reservoir for avian influenza (AI) viruses and pose an ongoing threat to commercial poultry flocks. Combining the (i) size of that population, (ii) their flight distances and (iii) their AI prevalence, the density of AI-infected dabbling ducks (DID) was calculated as a risk factor for the introduction of AI viruses into poultry holdings of Emilia-Romagna region, Northern Italy. Data on 747 poultry holdings and on 39 AI primary outbreaks notified in Emilia-Romagna between 2000 and 2017 were used to validate that risk factor. A multivariable Bayesian logistic regression was performed to assess whether DID could be associated with the occurrence of AI primary outbreaks. DID value, being an outdoor flock, hobby poultry trading, species reared, length of cycle and flock size were used as explanatory variables. Being an outdoor poultry flock was significantly associated with a higher risk of AI outbreak occurrence. The probability of DID to be a risk factor for AI virus introduction was estimated to be 90%. A DID cut-off of 0.23 was identified to define high-risk areas for AI virus introduction. Using this value, the high-risk area covers 43% of the region. Seventy-four per cent of the primary AI outbreaks have occurred in that area, containing 39% of the regional poultry holdings. Poultry holdings located in areas with a high DID value should be included in a risk-based surveillance programme aimed at AI early detection.


Assuntos
Animais Selvagens/virologia , Surtos de Doenças/veterinária , Patos/virologia , Vírus da Influenza A/isolamento & purificação , Influenza Aviária/transmissão , Doenças das Aves Domésticas/transmissão , Animais , Teorema de Bayes , Galinhas , Influenza Aviária/virologia , Itália , Modelos Estatísticos , Doenças das Aves Domésticas/virologia , Prevalência , Fatores de Risco
3.
Leukemia ; 30(12): 2293-2301, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27677742

RESUMO

The development and progression of chronic B-cell tumors depend on a complex microenvironmental network of cells that include monocyte-derived macrophages. In chronic lymphocytic leukemia (CLL) the survival of malignant cells is supported in vitro by nurse-like cells, which differentiate from CD14+ monocytes and have been identified as tumor-associated macrophages (TAMs). The role of the monocyte/macrophage lineage in CLL has been extensively studied in vitro, but only recently has been investigated in in vivo models. We here discuss how the cellular and molecular interactions that physiologically occur between B cells and macrophages can be subverted in chronic B lymphoid malignancies. Clinical approaches for the therapeutic targeting of TAMs are under evaluation. Promising strategies, along with a direct impact on the malignant cells, affect crucial pathways involved in the interaction of leukemic cells with TAMs. As an example, ibrutinib reduces CLL cell chemoattraction by inhibiting macrophage secretion of CXCL13. Lenalidomide and trabectedin prevent TAM recruitment mainly through CCL2 blockade. Most advanced strategies aim at depleting macrophages by targeting the CSF1/CSF1R pathway, which is fundamental for TAM survival. Of note, CSF1 transcripts are significantly more abundant in progressive CLL patients when compared with stable CLL and the frequency of CSF1R+ TAMs correlates with poor survival in hematological malignancies. The successful combination of CSF1R inhibition with currently available agents targeting malignant cells might represent the next therapeutic frontier in CLL. Conceivably these approaches may become applicable to numerous chronic B lymphoid malignancies.


Assuntos
Linfócitos B/patologia , Leucemia Linfocítica Crônica de Células B/patologia , Macrófagos/patologia , Linhagem da Célula , Progressão da Doença , Humanos
4.
J Dairy Sci ; 97(9): 5592-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24997661

RESUMO

For more than 30 yr, a control plan for Streptococcus agalactiae and Staphylococcus aureus has been carried out in more than 1,500 dairy herds of the province of Brescia (northern Italy). From 2010 to 2011, the apparent prevalence of Strep. agalactiae has been relatively stable around 10%, but the apparent prevalence of Staph. aureus has been greater than 40% with an increasing trend. The aim of this paper was to estimate and compare the diagnostic accuracy of 3 assays for the detection of Strep. agalactiae and Staph. aureus in bulk-tank milk samples (BTMS) in field conditions. The assays were a qualitative and a quantitative bacteriological culture (BC) for each pathogen and a homemade multiplex real-time PCR (rt-PCR). Because a gold standard was not available, the sensitivities (Se) and specificities (Sp) were evaluated using a Bayesian latent class approach. In 2012 we collected one BTMS from 165 dairy herds that were found positive for Strep. agalactiae in the previous 2-yr campaigns of eradication plan. In most cases, BTMS collected in these herds were positive for Staph. aureus as well, confirming the wide spread of this pathogen. At the same time we also collected composite milk samples from all the 8,624 lactating cows to evaluate the within-herd prevalence of Strep. agalactiae. Streptococcus agalactiae samples were cultured using a selective medium Tallium Kristalviolette Tossin, whereas for Staph. aureus, we used Baird Parker modified medium with added Rabbit Plasma Fibrinogen ISO-Formulation. In parallel, BTMS were tested using the rt-PCR. Regarding Strep. agalactiae, the posterior median of Se and Sp of the 2 BC was similar [qualitative BC: Se=98%, posterior credible interval (95%PCI): 94-100%, and Sp=99%, 95%PCI: 96-100%; quantitative BC: Se=99%, 95%PCI: 96-100%, and Sp=99%, 95%PCI: 95-100%] and higher than those of the rt-PCR (at 40 cycle threshold, Se=92%, 95%PCI: 85-97%; Sp=94%, 95%PCI: 88-98%). Also in case of Staph. aureus, the posterior medians of BC were generally higher than those of rt-PCR. In fact, although the Se of BC was slightly lower (rt-PCR at 40 cycle threshold, median Se=99%, 95%PCI: 97-100%, and qualitative BC, median Se=94%, 95%PCI: 87-99%), the Sp was much higher (rt-PCR at 40 cycle threshold, median Sp=67%, 95%PCI: 38-97%; qualitative BC, median Sp=95%; 95%PCI: 76-100%). Our study confirms that BC and rt-PCR are reliable diagnostic tools to detect Strep. agalactiae and Staph. aureus, and rt-PCR results should be confirmed by BC carried out on BTMS and possibly on composite milk samples.


Assuntos
Leite/microbiologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Staphylococcus aureus/isolamento & purificação , Streptococcus agalactiae/isolamento & purificação , Animais , Bovinos , DNA Bacteriano/análise , Feminino , Itália , Lactação , Mastite Bovina/epidemiologia , Mastite Bovina/microbiologia , Mastite Bovina/prevenção & controle , Sensibilidade e Especificidade , Infecções Estafilocócicas/veterinária , Staphylococcus aureus/genética , Staphylococcus aureus/crescimento & desenvolvimento , Infecções Estreptocócicas/veterinária , Streptococcus agalactiae/genética , Streptococcus agalactiae/crescimento & desenvolvimento
5.
Allergy ; 62(3): 293-300, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17298347

RESUMO

BACKGROUND: Epidemiological studies have documented large international variations in the prevalence of asthma, and 'westernization' seems to play an important role in the development of the disease. The aims of this study were to compare the prevalence of respiratory symptoms in migrant and nonmigrant children resident in Italy, and to examine the effect of length of time living in Italy. METHODS: Data were collected in a large cross-sectional study (SIDRIA-2) performed in 12 Italian centres, using standardized parental questionnaires. For the 29 305 subjects included in the analysis (6-7 and 13-14 years old), information about place of birth and parental nationality was available. RESULTS: There were 1012 children (3%) born outside of Italy, mainly in East Europe. Lifetime asthma and current wheeze were generally significantly less common among children born abroad than among children born in Italy (lifetime asthma: 5.4% and 9.7% respectively, P < 0.001; current wheeze: 5.2% and 6.9%, respectively, P = 0.04). Lower risks for lifetime asthma (prevalence odds ratio, POR = 0.39; 95% CI: 0.23-0.66) and current wheeze (POR = 0.72; 95% CI: 0.47-1.10) were found for children who had lived in Italy <5 years, while migrant children who had lived in Italy for 5 years or more had risks very similar to Italian children. CONCLUSIONS: Migrant children have a lower prevalence of asthma symptoms than children born in Italy. Prevalence increased with the number of years of living in Italy, suggesting that exposure to environmental factors may play an important role in the development of asthma in childhood.


Assuntos
Asma/epidemiologia , Emigração e Imigração , Sons Respiratórios , Adolescente , Criança , Estudos Transversais , Humanos , Itália/epidemiologia , Prevalência , Fatores de Risco , Inquéritos e Questionários , Fatores de Tempo
6.
J Environ Monit ; 8(12): 1219-26, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17133278

RESUMO

The present paper reports on a rapid method for the analysis of gaseous emissions from ceramic industry, based on ion mobility spectrometry (IMS) as a means for on-site monitoring of volatile organic compounds (VOCs) produced during tile baking. IMS was calibrated with a set of reference compounds (i.e. ethyl acetate, ethanol, ethylene glycol, diethylene glycol, acetaldehyde, formaldehyde, 2-methyl-1,3-dioxolane, 2,2-dimethyl-1,3-dioxolane, 1,3-dioxolane, 1,4-dioxane, benzene, toluene, cyclohexane, acetone, acetic acid) via air-flow permeation. The technique was tested on a laboratory-scale kiln and tiles prepared with selected glycol- and resin-based additives. Finally, the analytical method was applied to emissions from two industries in the Modena (Italy) ceramic area. The results of all experimental phases were compared to those obtained by solid phase micro-extraction/gas chromatography/mass spectrometry (SPME/GC/MS). IMS showed potential as a real-time monitoring device for quality assessment in ceramic industry emissions. IMS spectra, SPME/GC/MS data, relationship between additives/baking conditions and produced VOCs and advantages and limitations of both techniques will be discussed.


Assuntos
Poluentes Atmosféricos/análise , Cerâmica , Compostos Orgânicos/análise , Monitoramento Ambiental , Resíduos Industriais , Espectrometria de Massas/métodos , Compostos Orgânicos/química
7.
G Chir ; 25(6-7): 224-6, 2004.
Artigo em Italiano | MEDLINE | ID: mdl-15558983

RESUMO

Hydatidosis represents a form of helminthic zoonosis with a stronger medical, social and economic impact. It is endemic in some areas of the world including Mediterranean countries, and therefore Italy. The disease is often diagnosed in an advanced phase, due to the poor symptomatology in the early stages. The best treatment is surgery. Emergency surgery is similar to elective surgery, though in some cases is preferable only a drainage procedure until the stabilization of the genreal and local conditions of the patient allow a radical intervention. The Authors report on their five year experience of surgical treatment of compliated pulmonar hydatidosis pointing out that exeresis must be aimed at preserving pulmonar function as much as possible.


Assuntos
Equinococose Pulmonar/cirurgia , Adolescente , Adulto , Idoso , Equinococose Pulmonar/diagnóstico , Equinococose Pulmonar/diagnóstico por imagem , Emergências , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Pneumonectomia , Radiografia Torácica , Fatores de Tempo , Tomografia Computadorizada por Raios X
8.
G Chir ; 25(5): 171-4, 2004 May.
Artigo em Italiano | MEDLINE | ID: mdl-15382475

RESUMO

Celomic cysts (pericardiopleural or serous cysts) are rare, as they account for about 30% of all the homoplastic disembryogenetic lesions of the mediastinum. There is not usually a characteristic symptomatology associated with this anomaly, which is, however, easily diagnosed by means of the most common radiologic techniques. The TC together with the MRI provides all the necessary data for an appropriate management of the patient. The Authors report on their five year experience of the surgical treatment of celomic cysts, pointing out that surgery must be aimed at preserving pulmonary function as much as possible. They finally maintain that the first surgical approach should be video-thoracoscopic with the aid of a minithoracotomy, if necessary.


Assuntos
Cistos/cirurgia , Pericárdio , Doenças Pleurais/cirurgia , Adolescente , Adulto , Idoso , Cistos/diagnóstico , Feminino , Cardiopatias/diagnóstico , Cardiopatias/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Pleurais/diagnóstico
9.
G Chir ; 25(4): 137-9, 2004 Apr.
Artigo em Italiano | MEDLINE | ID: mdl-15283406

RESUMO

Among recurrent pleural effusions a role of remarkable importance is held by those combined with ascitis due to the difficulty of their treatment, even using widely tested techniques. The incidence of such pathology varies from 4% to 6% of patients suffering from cirrhotic pathology, reaching 10% in cases with advanced illnesses. Pleural effusions involve the right emithorax more frequently than the left one, but it can show up bilaterally too. Its etiopathogenesis is tied up to the direct passage of ascitic liquid into the chest and, during the past years, numerous theories have been described to explain this migration. The Authors report the case of a patient with interesting considerations for the diagnostic difficulties and the peculiarity of the treatment performed.


Assuntos
Ascite/cirurgia , Síndrome de Budd-Chiari/cirurgia , Derrame Pleural/cirurgia , Stents , Cirurgia Torácica Vídeoassistida , Veia Cava Inferior/cirurgia , Adulto , Ascite/etiologia , Síndrome de Budd-Chiari/complicações , Síndrome de Budd-Chiari/diagnóstico , Terapia Combinada , Constrição Patológica/complicações , Constrição Patológica/diagnóstico , Constrição Patológica/cirurgia , Diagnóstico Diferencial , Humanos , Masculino , Derrame Pleural/etiologia , Pleurodese , Veia Cava Inferior/patologia
10.
Anal Chem ; 73(16): 3824-7, 2001 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-11534703

RESUMO

Some improvements to the membrane introduction mass spectrometry (MIMS) technique, resulting in low-ppt detection limits for volatile organohalogen compounds (CX) in water (namely, chloroform, bromoform, bromodichloromethane, chlorodibromomethane, tetrachloroethylene, trichloroethylene, 1,1,1-trichloroethane, and carbon tetrachloride) and low-microgram per cubic meter detection limits for benzene, toluene, ethylbenzene, and xylenes (BTEX) in gaseous samples, are shown. A static MIMS configuration was compared to a dynamic one, the former requiring longer time to obtain the analytical response. A cryotrapping preconcentration step is introduced and linearity of response, mixture effects, and detection limits are presented. The instrumental setup consists of a hollow fiber silicone membrane, a water or air container, a cryofocusing trap based on Tenax adsorbent, a Peltier cell, and a Varian ion trap benchtop mass spectrometer is described. This instrumental setup, which we named membrane extraction trap focusing mass spectrometry, allowed the detection of CX in water at a concentration as low as 8 ppt and of benzene in air at 0.1 microg/m3. The whole assembly shows great potential for on-site routine monitoring of drinking water resources and urban and indoor air under current EU and Italian regulations.

11.
J Cardiovasc Surg (Torino) ; 42(4): 543-9, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11455294

RESUMO

BACKGROUND: Balloon expandable metal stents (BEMS) are used to treat restenosis following percutaneous transluminal angioplasty (PTA) and as primary treatment. Intimal proliferation (IP) and resultant restenosis occurs in 25-50% of patients despite all preventive measures. OBJECTIVE: to test the intra-arterial response to the insertion of a fibrin sealant (FS) coated BEMS vs an uncoated BEMS by measuring endothelization and IP. HYPOTHESIS: that a BEMS coated with FS will lead to rapid endothelization and prevent or reduce IP. RATIONALE: FS consists of fibrinogen and thrombin. Thrombin affects endothelial cell proliferation and reduces smooth muscle proliferation, the forerunner of IP and restenosis. Normal endothelium also releases substances that promote vascular relaxation and normal smooth muscle tone regulation. METHODS: Thirty-40 kg pigs (EA), Palmaz-Shatz BEMS (Cordis), FS Tissucol (Baxter Immuno). Stents were uniformly coated with FS in a special mold. Both coated and uncoated stents were mounted on balloon catheters and deployed caudad in the carotid arteries via an arteriotomy. Angiograms were obtained postdeployment. All specimens were examined grossly, photographed then fixed for histology and in some cases, scanning electron microscopy (SEM). RESULTS: Fifteen animals form this preliminary report. Sacrifice at five days as per original protocol showed insufficient stent incorporation. Thereafter 1/2 of the animals were sacrificed at 15 days and 1/2 at 30 days. PATENCY: coated stents: 6 patent, 9 thrombosed. UNCOATED: 7 patent, 8 thrombosed. Of five EA given postoperatively low molecular weight heparin (LMWH) 4 animals had patent stents 80%. HISTOLOGY: varying degrees of IP were seen in all specimens. In general the coated stents showed a greater degree than the uncoated. STENOSIS: presacrifice angiography revealed that where the stents were patent no stenosis was present, in fact, some demonstrated mild dilatation. This was particularly the case with the coated stents. CONCLUSIONS: Coating stents with FS is not detrimental. IP in these EA at 30 days did not produce stenosis. Postoperative LMWH appears helpful in maintaining patency in a thrombogenic experimental animal. Further study maintaining EA for 6-12 months should resolve whether the IP seen had achieved its maximum expression or would progress and produce stenosis.


Assuntos
Artérias Carótidas/crescimento & desenvolvimento , Endotélio Vascular/crescimento & desenvolvimento , Adesivo Tecidual de Fibrina , Stents , Angioplastia com Balão , Animais , Constrição Patológica/etiologia , Constrição Patológica/prevenção & controle , Suínos , Túnica Íntima/crescimento & desenvolvimento , Grau de Desobstrução Vascular
12.
Rapid Commun Mass Spectrom ; 15(9): 665-9, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11319786

RESUMO

Matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS) has been investigated as a tool for accurate determination of the molecular mass of synthetic analogues of prazosine, a molecule used for the treatment of hypertension. Samples were dissolved in methanol, mixed with mass calibration standards, and crystallised on the target with alpha-cyano-4-hydroxycinnamic acid as matrix. Acquisition of spectra was rapidly completed in reflectron mode, allowing high resolution (6000-10000) and sensitive (about 1-10 pmol of sample on target) determination of the synthetic products. The results show the effectiveness of MALDI-TOFMS for accurate mass determination of these fairly large molecules, which are otherwise difficult to analyse by other high-resolution mass spectrometric techniques.


Assuntos
Antagonistas Adrenérgicos alfa/análise , Prazosina/análogos & derivados , Prazosina/análise , Calibragem , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrofotometria Ultravioleta
13.
Rapid Commun Mass Spectrom ; 14(15): 1417-24, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10920364

RESUMO

Distillery wastewaters generated by ethanol production from fermentation of sugar-cane molasses, named vinasses, lead to important ecological impact due to their high content of soluble organic matter and their intense dark-brown color. Taking advantage of the well-known ability of white-rot fungi to degrade an extensive variety of organic pollutants, the capacity of Trametes sp. I-62 (CECT 20197) to detoxify this type of effluents was evaluated. In this work, pyrolysis/gas chromatography/mass spectrometry was applied to the chemical characterization of several fractions of Cuban distillery wastewater as well as to monitoring the changes which occurred after fungal treatment with this white-rot basidiomycete. Maximum effluent decolorization values and chemical oxygen demand reduction attained after seven days of fungal treatment were 73.3 and 61.7%, respectively, when 20% (v/v) of distillery vinasses was added to the culture medium. Under these conditions a 35-fold increase in laccase production by Trametes sp. I-62 was measured, but no manganese peroxidase activity could be detected. The pyrolysis/gas chromatography/mass spectrometry results showed a decrease in a number of pyrolysis products after seven days of fungal treatment, mainly furan derivatives. The decrease in the relative areas of these compounds could be related to the vinasse color-removal associated with melanoidin degradation. All these results indicated the potential use ofTrametes sp. I-62 in the detoxification of recalcitrant distillery vinasses.


Assuntos
Resíduos Industriais/análise , Polyporaceae/química , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/análise , Fermentação , Cromatografia Gasosa-Espectrometria de Massas , Lacase , Oxirredutases/análise , Oxigênio/análise
14.
Rapid Commun Mass Spectrom ; 14(14): 1275-9, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10918380

RESUMO

In this work, electron-impact mass spectroscopy (EI-MS) was employed on a wide range of sterol compounds in order to study their behaviour with regard to their functional groups. In particular, some specific mechanisms of fragmentation occurring in these substrates (i.e. retro-Diels-Alder reaction, neutral molecules eliminations, specific hydrogen migrations) were investigated. Loss of the alkyl side chain and of the D ring were observed in all cases. Finally, a classification of sterols on the basis of characteristic mass spectral fragments is suggested, and further applications to substrates with functional groups on positions other than the A and B rings is proposed.


Assuntos
Ésteres do Colesterol/química , Animais , Ésteres do Colesterol/análise , Humanos , Espectrometria de Massas/métodos , Oxirredução
15.
Rapid Commun Mass Spectrom ; 14(10): 905-10, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-10825255

RESUMO

Some fractions of beer-factory wastewaters represent an important environmental concern owing to their high content of polyphenols and dark-brown color. The capacity of Coriolopsis gallica to preferentially degrade lignin has been successfully applied in our laboratory to the biotreatment and decolorization of paper-industry effluents. In this work, the ability of this white-rot fungus to degrade high-tannin-containing wastewaters is evaluated. Under all the conditions studied, effluent decolorization and chemical oxygen demand reduction achieved by C. gallica at day 12 of incubation were close to 50 and 65%, respectively. No adhesion of dark color to the fungal mycelium was observed suggesting that decolorization could be ascribed to C. gallica degradation systems. Mycelium dry-weight values showed that C. gallica is tolerant to relatively high tannin content present in the effluent samples. In the sample containing the highest effluent concentration (60% v/v), dry-weight values suggested an inhibition of fungal growth at day 6 of incubation and a further adaptation of the fungus to the stressing tannin effect at day 12 of fungal treatment. Pyrolysis/gas chromatography/mass spectrometry results showed a decrease of polyphenols pyrolysis products, mainly phenol and guaiacol, with the incubation time. All these results indicate the potential use of C. gallica in bioremediation of tannin-containing industrial wastewaters and in other applications where a reduction in polyphenols content is required.


Assuntos
Flavonoides , Cromatografia Gasosa-Espectrometria de Massas/métodos , Polyporales/metabolismo , Taninos/metabolismo , Eliminação de Resíduos Líquidos , Poluentes Químicos da Água/metabolismo , Cerveja , Biodegradação Ambiental , Fenóis/metabolismo , Polímeros/metabolismo , Polifenóis , Polyporales/crescimento & desenvolvimento
16.
J Appl Physiol (1985) ; 88(4): 1365-73, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10749831

RESUMO

The pattern of a spatial structure that repeats itself independently of the scale of magnification or resolution is often characterized by a fractal dimension (D). Two-dimensional low-pass filtering, which may serve as a method to assess D, was applied to functional images of pulmonary perfusion measured by positron emission tomography. The corner frequency of a low-pass filter is inversely proportional to the resolution scale. The method was applied to three types of images: random noise images, synthetic fractal images, and positron emission tomographic images of pulmonary perfusion. Images were processed with two-dimensional low-pass filters of decreasing corner frequencies, and a spatial heterogeneity index, the coefficient of variation, was calculated for each low-pass-filtered image. The natural logarithm of the coefficient of variation scaled linearly with the natural logarithm of the resolution scale for the PET images studied (average R(2) = 0.99). D ranged from 1.25 to 1.36 for the residual distribution of pulmonary perfusion after vertical gradients were removed by linear regression. D of the same data without removal of vertical gradients ranged from 1.11 to 1.14, but the fractal plots had systematic deviations from linearity and a lower linear correlation coefficient (R(2) = 0. 96). The method includes all data in the lung field and is insensitive to the effects of misregistration. We conclude that low-pass filtering offers new insights into the interpretation of D of two-dimensional functional images as a measure of the frequency content of spatial heterogeneity.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Circulação Pulmonar , Tomografia Computadorizada de Emissão/métodos , Fractais , Humanos , Pulmão/irrigação sanguínea , Fluxo Sanguíneo Regional
17.
J Chromatogr Sci ; 38(2): 55-60, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10677833

RESUMO

Manual solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS) is applied for the determination of polycyclic aromatic hydrocarbons (PAHs) from natural matrix through a distilled water medium. Seven of the 16 PAH standards (naphthalene, acenaphthene, fluorene, anthracene, fluoranthene, pyrene, benzo[a]anthracene) are spiked on a marine muddy sediment. The samples, containing PAHs in the range of 10-20 ppm, are then aged at room temperature more than 10 days before analysis. The influence of the matrix, SPME adsorption time, pH, salt content, and SPME adsorption temperature are investigated. The reproducibility of the technique is less than 13% (RDS) for the first 6 considered PAHs and 28% (RDS) for benzo(a)anthracene with a fiber containing a 100-micron poly dimethylsiloxane coating. Linearity extended in the range of 5-50 picograms for PAHs direct injection, 5-70 picograms for PAHs in water, and 1-170 picograms for PAHs in sediment. The detection limit is estimated less than 1 microgram/kg of dry sample for the first 6 considered PAHs in sediment and 1.5 micrograms/kg of dry sample for benzo(a)anthracene using the selected ion monitoring mode in GC-MS. The recoveries of the considered PAHs are evaluated.


Assuntos
Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes Químicos da Água/análise , Adsorção , Calibragem , Cromatografia Gasosa-Espectrometria de Massas , Concentração de Íons de Hidrogênio , Indicadores e Reagentes , Itália , Soluções , Temperatura
18.
Acta Biomed Ateneo Parmense ; 71(5): 159-66, 2000.
Artigo em Italiano | MEDLINE | ID: mdl-11450118

RESUMO

Repeat cardiac surgical procedures are associated with increased technical difficulty and risk related to the presence of dense adhesions between the heart and the surrounding tissues. We examined the efficacy of a bioabsorbable membrane containing hyaluronic acid in the prevention of pericardial adhesions in 23 rabbits. After thoracotomy and pericardiotomy the animals were divided in three groups: Group 1 (9 animals) in which the epicardial surfaces were covered by Seprafilm membrane, Group 2 (9 animals) treated with both Seprafilm membrane and Sepracoat solution, and Group 3 (5 animals) as controls. The animals were reexplored at 10, 30 and 60 days: no intrapericardial adhesions were found in all the animals of Group 2. In 4 animals (44%) of Group 1 localized post-operative adhesions were detected, in absence of epicardial hyperplasia; in contrast, dense and diffuse adhesions were present in all the control animals. The use of the bioabsorbable membrane Seprafilm significantly reduces adhesion formation even if better results are possible with the previous intrapericardial administration of Sepracoat solution. Application of these biocompatible products could reduce the technical difficulty and risk of repeat surgical procedures.


Assuntos
Materiais Biocompatíveis , Ácido Hialurônico , Membranas Artificiais , Pericárdio , Animais , Cardiomiopatias/prevenção & controle , Feminino , Masculino , Coelhos , Aderências Teciduais/prevenção & controle
19.
Rapid Commun Mass Spectrom ; 13(20): 2049-53, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10510419

RESUMO

The analysis of organic pollutants in drinking water is a topic of wide interest, reflecting on public health and life quality. Many different methodologies have been developed and are currently employed in this context, but they often require a time-consuming sample pre-treatment. This step affects the recovery of the highly volatile compounds. Trace analysis of volatile organic pollutants in water can be performed 'on-line' by membrane inlet mass spectrometry (MIMS). In MIMS, the sample is separated from the vacuum of the mass spectrometer by a thin polymeric hollow-fibre membrane. Gases and organic volatile compounds diffuse and concentrate from the sample into the hollow-fibre membrane, and from there into the mass spectrometer. The main advantages of the technique are that no pre-treatment of samples before analysis is needed and that it has fast response times and on-line monitoring capabilities. This paper reports the set-up of the analytical conditions for the analysis of volatile organohalogen compounds (chloroform, bromoform, bromodichloromethane, chlorodibromomethane, tetrachloroethylene, trichloroethylene, 1,1,1-trichloroethane, and carbon tetrachloride). Linearity of response, repeatability, detection limits, and spectra quality are evaluated.


Assuntos
Hidrocarbonetos Halogenados/análise , Espectrometria de Massas/métodos , Poluentes da Água/análise , Água/química , Tetracloreto de Carbono/análise , Clorofórmio/análise , Hidrocarbonetos Bromados/análise , Controle de Qualidade , Reprodutibilidade dos Testes , Tetracloroetileno/análise , Tricloroetanos/análise , Tricloroetileno/análise , Trialometanos , Volatilização
20.
Surg Endosc ; 12(8): 1046-50, 1998 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-9685540

RESUMO

BACKGROUND: Laparoscopic colon anastomosis are technically demanding. A new technique for colon resection and anastomosis using a combined laparoendoscopic approach is presented. METHODS: In 10 pigs, pneumoperitoneum was induced and 5 trocars were placed. A sigmoid segment was isolated; a vein stripper was inserted from the anus, and the head was secured with a tie; the segment was intussuscepted pulling the stripper out; 4 seromuscular sutures were placed at the anastomotic site and fibrin glue was spread all around; an electrical wire loop, introduced via a colonoscope, was used to resect the intussuscepted segment that was removed from the anus. RESULTS: All animals but one survived until sacrifice at 30, 60, 90, and 120 days. Macroscopically, the anastomosis appeared well healed; microscopically, after 90 days, there was a complete restitutio ad integrum of the intestinal wall. CONCLUSIONS: This technique is feasible and quick; it could be used clinically in small tumors not removable endoscopically.


Assuntos
Canal Anal/cirurgia , Colo/cirurgia , Colonoscopia/métodos , Adesivo Tecidual de Fibrina/uso terapêutico , Laparoscopia/métodos , Adesivos Teciduais/uso terapêutico , Canal Anal/patologia , Anastomose Cirúrgica/métodos , Animais , Colo/patologia , Colonoscopia/mortalidade , Terapia Combinada , Modelos Animais de Doenças , Estudos de Viabilidade , Feminino , Laparoscopia/mortalidade , Taxa de Sobrevida , Suínos , Resultado do Tratamento
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