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1.
Toxicol Lett ; 316: 20-26, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31465813

RESUMO

Health-care personnel handling antineoplastic drugs could be at risk for adverse health effects. We aimed to evaluate genotoxic and cytotoxic effects of antineoplastic drug exposure of personnel preparing and administering such drugs in three Oncology Hospitals in Italy enrolling 42 exposed subjects and 53 controls. Furthermore, we aimed to study the possible influence of XRCC1 and hOGG1 DNA repair genes polymorphisms on genotoxicity induced on buccal cells. We performed workplace and personal monitoring of some drugs and used exposure diary informations to characterize the exposure. Urinary 5-FU metabolite (α-fluoro-ß-alanine) was measured. Buccal Micronucleus Cytome (BMCyt) assay was used to evaluate DNA damage and other cellular anomalies. GEM and 5-FU contamination was found in 68% and 42% of wipe/swab samples respectively. GEM deposition was found on workers' pads while no α-fluoro-ß-alanine was found. BMCyt-assay showed higher genotoxicity and cytotoxicity on nurses administering antineoplastics than on preparators and controls. Among micronucleus (MN) positive (with MN frequency higher than 1.5‰) exposed subjects, the percentage of those carrying XRCC1 mut/het genotype was higher than in MN positive-controls. Using the sensitive BMCyt assay, we demonstrated that handling antineoplastics still represents a potential occupational health risk for workers that should be better trained/informed regarding such risks.


Assuntos
Antineoplásicos/efeitos adversos , Desoxicitidina/análogos & derivados , Monitoramento Ambiental/métodos , Fluoruracila/efeitos adversos , Micronúcleos com Defeito Cromossômico/induzido quimicamente , Testes para Micronúcleos , Mucosa Bucal/efeitos dos fármacos , Recursos Humanos de Enfermagem Hospitalar , Exposição Ocupacional/efeitos adversos , Saúde Ocupacional , Enfermagem Oncológica , Adulto , Antineoplásicos/urina , Biomarcadores/urina , Estudos de Casos e Controles , DNA Glicosilases/genética , Desoxicitidina/efeitos adversos , Desoxicitidina/urina , Feminino , Fluoruracila/urina , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/metabolismo , Exposição Ocupacional/prevenção & controle , Polimorfismo Genético , Medição de Risco , Fatores de Risco , Urinálise , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/genética , Gencitabina
2.
Eur Rev Med Pharmacol Sci ; 20(12): 2630-3, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27383315

RESUMO

OBJECTIVE: Rickettsia conorii is responsible for the Mediterranean Spotted Fever. Recently, new rickettsial species have been recognized in Europe and implicated in human diseases. Clinical features often differ greatly from each other, but non-severe liver involvement is frequently observed during any rickettsial infection. CASE REPORT: We describe the unique case of a patient presented with significant high aminotransferase levels due to the first human R. aeschlimannii infection ever detected in Italy. The hypothesis of rickettsiosis was made on the basis of a comprehensive medical history and was confirmed by serological tests. Molecular analyses made on a sample of hepatic tissue revealed the presence of a rickettsial species never found before in human liver. CONCLUSIONS: A brief review of the literature is reported to highlight how relevant this case is and to remind that rickettsioses should be in the differential diagnoses of acute hepatitis, considering mostly the recent spread of new rickettsial species.


Assuntos
Hepatite/microbiologia , Infecções por Rickettsia , Rickettsia , Adulto , Diagnóstico Diferencial , Hepatite/diagnóstico , Humanos , Masculino , Infecções por Rickettsia/diagnóstico , Infecções por Rickettsia/microbiologia
3.
J Microsc ; 259(3): 173-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25865182

RESUMO

With the expansion of the production and applications of multiwalled carbon nanotubes (MWCNTs) in several industrial and science branches, the potential adverse effects on human health have attracted attention. Numerous studies have been conducted to evaluate how chemical functionalization may affect MWCNT effects; however, controversial data have been reported, showing either increased or reduced toxicity. In particular, the impact of carboxylation on MWCNT cytotoxicity is far from being completely understood. The aim of this work was the evaluation of the modifications induced by carboxylated-MWCNTs (MWCNTs-COOH) on cell surface and the study of cell-MWCNT-COOH interactions by means of field emission scanning electron microscope (FESEM). Human pulmonary epithelial cells (A549) were incubated with MWCNTs-COOH for different exposure times and concentrations (10 µg/mL for 1, 2, 4 h; 5, 10, 20 µg/mL for 24 h). At short incubation time, MWCNTs-COOH were easily observed associated with plasma membrane and in contact with microvilli. After 24 h exposure, FESEM analysis revealed that MWCNTs-COOH induced evident changes in the cellular surface in comparison to control cells: treated cells showed blebs, holes and a depletion of the microvilli density in association with structure modifications, such as widening and/or lengthening. In particular, an increase of cells showing holes and microvilli structure alterations was observed at 20 µg/mL concentration. FESEM analysis showed nanotube agglomerates, of different sizes, entering into the cell with two different mechanisms: inward bending of the membrane followed by nanotube sinking, and nanotube internalization directly through holes. The observed morphological microvilli modifications, induced by MWCNTs-COOH, could affect epithelial functions, such as the control of surfactant production and secretion, leading to pathological conditions, such as alveolar proteinosis. More detailed studies will be, however, necessary to examine in depth the effects induced by MWCNTs-COOH and, in particular, the timing of the MWCNT-COOH-cell interaction.


Assuntos
Membrana Celular/ultraestrutura , Células Epiteliais/fisiologia , Células Epiteliais/ultraestrutura , Microvilosidades/ultraestrutura , Nanotubos de Carbono/toxicidade , Linhagem Celular Tumoral , Sobrevivência Celular , Células Epiteliais/citologia , Humanos , Microscopia Eletrônica de Varredura , Nanotubos de Carbono/ultraestrutura , Propriedades de Superfície
4.
Int J Immunopathol Pharmacol ; 23(4): 1245-52, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21244774

RESUMO

Although several reports have correlated Chlamydophila pneumoniae (CP) infection with carotid endarterectomy and coronary stent, no data have been reported on the potential relationship between this pathogen and carotid artery stenting (CAS). Hence, we evaluated 47 subjects, 27 symptomatic and 20 asymptomatic, before CAS intervention and during the follow up, for the presence of CP DNA and anti-CP antibodies, including chlamydial HSP60 (Cp-HSP60). Before stent placement, CP DNA was detected exclusively in symptomatic patients, all of whom were also positive for CP IgG and IgA and 85.7 percent of them also had CP-HSP60 antibodies. At the follow-up, all CP DNA positive and 11 out of the 13 symptomatic patients with Cp-HSP60 antibodies became negatives. In contrast, no change was observed for CP- IgA antibodies. Despite the small number of patients, the present study advocates an important role of CP infection in symptomatic patients with carotid artery disease. Our findings also suggest that stent placement and/or therapy might have a role in favouring resolution of inflammation, though not affecting persistence of CP infection.


Assuntos
Estenose das Carótidas/terapia , Infecções por Chlamydophila/etiologia , Chlamydophila pneumoniae , Stents/microbiologia , Idoso , Anticorpos Antibacterianos/sangue , Proteína C-Reativa/análise , Chaperonina 60/imunologia , DNA Bacteriano/análise , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placa Aterosclerótica/microbiologia , Fatores de Risco
6.
Int J Immunopathol Pharmacol ; 21(2): 421-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18547488

RESUMO

Chlamydophila pneumoniae has been implicated in atherosclerosis, but the role of this obligate intracellular pathogen in the development of the above pathology is still unclear. In particular, its presence and quantitative distribution within lesional areas has not yet been defined. We studied 18 carotid biopsies obtained from patients undergoing endoartherectomy. By laser microdissection (LCM), two different sites (intra-plaque and plaque-adjacent areas) were taken from each lesion, and the presence and quantity of the pathogen DNA were determined by real-time polymerase chain reaction (Real-time PCR). A total of 8 plaques, exclusively from patients with unstable angina, were positive in real-time PCR. The bacterial DNA was detected in both lesional areas of 3 plaques which contained the highest number of DNA copies (1,900 to 2,200 copy numbers), while C. pneumoniae DNA was detected only in the intra-plaque area of the other 5 positive (500 to 1,600 copy numbers). No C. pneumoniae DNA was found in the other 10 plaques of which 6 were from patients with unstable angina and 4 from stable angina patients. No DNA from Helicobacter pylori or Cytomegalovirus was found in any plaque. This is the first report where both the target lesion and an adjacent reference site were evaluated for the presence of C. pneumoniae DNA by the combination of LCM and Real-time PCR assays. The integration of these two methodologies offer an excellent tool for in situ studies and may help to elucidate the putative role of C. pneumoniae in atherosclerosis.


Assuntos
Aterosclerose/microbiologia , Infecções por Chlamydia/microbiologia , Chlamydophila pneumoniae/química , DNA Bacteriano/análise , Microdissecção/métodos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Idoso , Aterosclerose/patologia , Artérias Carótidas/microbiologia , Artérias Carótidas/patologia , Infecções por Chlamydia/patologia , Chlamydophila pneumoniae/genética , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Endarterectomia das Carótidas , Feminino , Humanos , Lasers , Masculino , Pessoa de Meia-Idade
7.
G Ital Med Lav Ergon ; 29(3 Suppl): 286-7, 2007.
Artigo em Italiano | MEDLINE | ID: mdl-18409689

RESUMO

Genotoxic and oxidative effect of airborne particulate matter collected in a coke plant were evaluated on lung epithelial cells (A549). We aimed to clarify the mechanism of action of complex mixtures of PAHs and to identify biomarkers of effect of lung cancer. Particulate matter was analysed by GC/MS. Genotoxic and oxidative effects induced by the exposure to the extract were evaluated by Fpg comet assay. The cells were exposed for 30 min, 2h and 4h to 0.01%, 0.02% and 0.05% of the extract. We evaluated comet percentage and analysed tail moment values of exposed and unexposed cells treated with Fpg enzyme (TMenz) and untreated (TM) that indicate respectively oxidative and direct DNA damage. We found 0.328 ng/m3 of pyrene, 0.33 ng/m3 of benzo(a)anthracene, 1.073 ng/m3 of benzo(b)fluoranthene, 0.22 ng/m3 of benzo(k)fluoranthene, 0.35 ng/m3 of benzo(a)pyrene, 0.079 ng/m3 of dibenzo(a,h)anthracene and 0.40 ng/m3 of benzo(g,h,i)perylene. A dose-dependent increase, although not significant, of TM and TMenz in the exposed cells in respect to controls was found that indicates a slight increase of both direct and oxidative damage in exposed cells. A slight increase of comet percentage was found at the highest dose. We show the high sensibility of comet assay to measure early DNA damage also at low doses suggesting the use of such test on A549 to evaluate on target organ the effects of complex mixtures of genotoxic substances.


Assuntos
Poluentes Atmosféricos/toxicidade , Indústrias Extrativas e de Processamento , Pulmão/citologia , Pulmão/efeitos dos fármacos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Células Cultivadas , Humanos , Testes de Mutagenicidade , Oxirredução
9.
Ann Occup Hyg ; 50(3): 211-8, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16344288

RESUMO

Paving workers are exposed during road paving to several polycyclic aromatic hydrocarbons (PAHs) contained in asphalt fumes. In this study early genotoxic and oxidative effects of exposure to bitumen fumes were evaluated in 19 paving workers and 22 controls. Environmental and biological monitoring of exposure was carried out, measuring, on personal air samples from exposed workers collected during three working days, the concentration of 14 PAHs and urinary OH-pyrene at the end of each of the three working days. Genotoxic effect was evaluated analysing sister chromatid exchange (SCE) frequency and direct-oxidative DNA damage by formamido-pyrimidine-glycosylase (Fpg)-modified comet assay on lymphocytes. Tail moment values from Fpg-enzyme treated cells (TMenz) and from untreated cells (TM) were used as parameters of direct and oxidative DNA damage, respectively. For each subject, the TMenz/TM ratio >2.0 was used to indicate the presence of oxidative damage. DNA damage was also evaluated analysing comet percentage. Personal air samples showed low level of total PAHs (2.843 microg m(-3)) with prevalence of 2-3 ring PAHs (2.693 microg m(-3)). Urinary OH-pyrene after work-shift of the three working days was significantly higher than that found at the beginning of the working week. SCE analysis did not show any difference between two groups while an oxidative DNA damage was found in 37% of exposed with respect to the absence in controls. Comet percentage was significantly higher (P = 0.000 ANOVA) in the exposed than in controls. The results demonstrate the high sensitivity of comet assay to assess early oxidative effects induced by exposure to bitumen fumes at low doses and confirm the suitability of urinary OH-pyrene as a biomarker of PAH exposure. In conclusion the study suggests the use of Fpg-modified comet test as a biomarker of early genotoxic effects and that of urinary OH-pyrene as a biomarker of PAH exposure to furnish indications in terms of characterization, prevention and management of risk in occupational exposure to mixtures of potentially carcinogenic substances.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Dano ao DNA , Exposição Ocupacional/efeitos adversos , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Troca de Cromátide Irmã/efeitos dos fármacos , Adulto , Poluentes Ocupacionais do Ar/análise , Biomarcadores/urina , Monitoramento Ambiental/métodos , Humanos , Hidrocarbonetos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional/análise , Estresse Oxidativo , Hidrocarbonetos Policíclicos Aromáticos/análise , Pirenos/análise , Fumar/urina
10.
G Ital Med Lav Ergon ; 27(3): 297-9, 2005.
Artigo em Italiano | MEDLINE | ID: mdl-16240578

RESUMO

Paving workers are exposed during road paving to several PAHs contained in asphalt fumes. We aimed to evaluate early genotoxic and oxidative effects in 19 paving workers and 22 controls. We analysed sister chromatide exchange (SCE) frequency as marker of genotoxicity. Moreover we assessed oxidative DNA damage by Fpg-modified comet assay on lymphocytes calculating tail moment values from fpg-enzyme treated cells (TMenz) and from untreated cells (TM). For each subject the TMenz/TM ratio higher than 2.0 was used to indicate the presence of oxidative damage. We also evaluated DNA damage analysing comet percentage. SCE analysis didn't show any difference between exposed and control groups. We found oxidative DNA damage in 37% of exposed in respect to the absence in controls. Comet percentage was significantly higher in the exposed than in controls. The results demonstrate the high sensitivity of comet assay to assess early oxidative effects induced by exposure to PAH mixtures at low doses and suggest the use of this biomarker in the characterization, prevention and management of risk induced by occupational exposure to mixtures of potentially carcinogenic substances.


Assuntos
Ensaio Cometa , Hidrocarbonetos/efeitos adversos , Mutagênicos , Exposição Ocupacional , Hidrocarbonetos Policíclicos Aromáticos/efeitos adversos , Adulto , Células Cultivadas , Dano ao DNA , Humanos , Linfócitos/efeitos dos fármacos , Estresse Oxidativo , Oxigênio/metabolismo , Fatores de Risco , Sensibilidade e Especificidade , Troca de Cromátide Irmã , Fumar/efeitos adversos , Fatores de Tempo
11.
J Biol Regul Homeost Agents ; 19(3-4): 136-40, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16602628

RESUMO

Inflammatory processes contribute to the pathogenesis and complications of atherosclerosis and coronary heart disease (CHD). Several findings indicate that chlamydial heat shock proteins (HSP) may represent a particularly strong antigenic stimulus, able to induce specific humoral (Ab) and T-cell-mediated immune responses (CMI) linking infection by Chlamydia pneumoniae (CP) to immuno-pathological sequelae such as atherosclerosis and CHD. We have here evaluated the ability of chlamydial recombinant (r) HSP60 and rHSP10 to induce specific immune responses in human peripheral blood lymphocytes and in murine models. rHSP60, but not rHSP10, was shown to induce proliferation and Interferon-gamma secretion in lymphocytes of randomly selected blood donors, as well as to generate and detect delayed-type hypersensitivity response in HSP60-vaccinated mice. Overall, the present study provides new hints to evaluate a previous exposition to CP using rHSP60 in humans. Thus the evaluation of specific HSP60 CMI response in healthy subject could be useful to monitor the reactivity to Chlamydia pneumoniae possibly providing a link to CHD pathologies.


Assuntos
Proteínas de Bactérias/imunologia , Chaperonina 60/imunologia , Chlamydophila pneumoniae/imunologia , Linfócitos T/imunologia , Animais , Antígenos de Bactérias/genética , Aterosclerose/etiologia , Linfócitos B/imunologia , Proteínas de Bactérias/genética , Chaperonina 60/genética , Chlamydophila pneumoniae/genética , Chlamydophila pneumoniae/patogenicidade , Doença das Coronárias/etiologia , Humanos , Imunização , Técnicas In Vitro , Inflamação/etiologia , Camundongos , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia
12.
Eur J Neurol ; 11(5): 321-7, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15142225

RESUMO

Retrospective and cross-sectional studies have suggested that both bacterial and viral infections may be risk factors for atherosclerosis, ischemic stroke and acute coronary events. The correlation between Chlamydia pneumoniae and atherosclerosis remains a source of controversy. Our case-control study is aimed at evaluating the frequency of C. pneumoniae infection in a cohort of young adults with recent cerebrovascular disease and in particular etiologic stroke subtypes. Chlamydia pneumoniae IgG, IgM and IgA antibodies were evaluated by microimmunofluorescence method and antibody titers to both recombinant antigens chlamydial outer protein 2 and 60-kDa chlamydial heat shock protein (HSP60) by ELISA. The two groups differed with regard to the prevalence of C. pneumoniae IgA (P < 0.001) and IgG (P < 0.0001), as well as the titer of anti-R-HSP60 IgG (P < 0.001). We found an increase in IgA titers, suggestive of persistent, chronic active infection, in 16 patients in whom the etiology of the cerebral ischemic event was large-vessel atherothrombosis. Persistent, active C. pneumoniae infection may be an additional risk factor for ischemic stroke mainly of atherotrombotic origin in young subjects. However, a large-scale prospective confirmation of our findings is required.


Assuntos
Infecções por Chlamydia/complicações , Chlamydophila pneumoniae , Acidente Vascular Cerebral/complicações , Adolescente , Adulto , Fatores Etários , Anticorpos Antibacterianos/sangue , Antígenos de Bactérias/sangue , Antígenos de Bactérias/imunologia , Estudos de Casos e Controles , Chaperonina 60/sangue , Chaperonina 60/imunologia , Infecções por Chlamydia/imunologia , Chlamydophila pneumoniae/imunologia , Estudos de Coortes , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Imunofluorescência/métodos , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Estudos Soroepidemiológicos , Acidente Vascular Cerebral/imunologia
13.
Ann Ig ; 15(6): 851-61, 2003.
Artigo em Italiano | MEDLINE | ID: mdl-15049542

RESUMO

Chlamydia pneumoniae (C. p.) is an intracellular parasite directly involved in respiratory disease and more recently in chronic degenerative pathologies as atherosclerosis and asthma. Its peculiar life cycle makes cultural isolation difficult, thus, troublesome the diagnosis of the disease. Serology is so far the most common method of diagnosis of the, although the indirect based evidence of the serology may give clinically misleading results. Nucleic acid amplification methods offer indeed rapid, reliable and low cost assessment pathogen bacteria isolation, with relevant benefits for the patient's management. These molecular methods are nowadays essential in presence of bacteria of difficult cultivation or method inconsistent with temporal clinical needs, for they allow to rapidly detect even nucleic acid traces of the infectious agent, providing direct evidence of its presence in the biological samples and hence the relevant therapy. Nucleic acid methods are extensively applied in laboratory diagnosis of Chlamydia trachomatis bringing about the development of sensitive and reliable commercial kits. This review analyses the literature of the genic amplification methods in the search of C. p. in clinical samples highlighting methodological and diagnostic aspects. Although genic amplification methods have been implemented presently by the clinical research labs only, it is anticipated that through their standardisation they could be used by most clinical microbiology laboratories.


Assuntos
Infecções por Chlamydophila/diagnóstico , Chlamydophila pneumoniae , Pneumonia Bacteriana/diagnóstico , Chlamydophila pneumoniae/genética , Chlamydophila pneumoniae/isolamento & purificação , Humanos , Técnicas de Diagnóstico Molecular , Reação em Cadeia da Polimerase
14.
J Clin Microbiol ; 39(12): 4554-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11724882

RESUMO

The aim of this study was to characterize a Bartonella strain (BA-1) isolated from a blood culture of an Italian, human immunodeficiency virus-positive patient with bacillary angiomatosis. We analyzed the isolate using molecular biology methods such as whole-cell fatty acid analysis, PCR-restriction fragment length polymorphism analysis, type-specific 16S rRNA PCRs, sequence analysis of the 16S rRNA, pulsed-field gel electrophoresis, and arbitrarily primed PCR. The BA-1 isolate turned out to be a Bartonella quintana strain, similar but not identical to B. quintana Oklahoma, which was used as a control strain.


Assuntos
Angiomatose Bacilar/microbiologia , Bartonella quintana/classificação , Bartonella quintana/genética , Infecções por HIV/complicações , Adulto , Técnicas de Tipagem Bacteriana/métodos , Bartonella quintana/isolamento & purificação , Eletroforese em Gel de Campo Pulsado , Ácidos Graxos/análise , Humanos , Itália , Masculino , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
J Clin Microbiol ; 39(6): 2254-60, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11376066

RESUMO

Between 1993 and 1998, we isolated Borrelia burgdorferi sensu lato from 55 of the 119 patients with clinically diagnosed Lyme borreliosis who were admitted to "San Martino" Hospital in Belluno, Veneto, an Adriatic region in northeastern Italy where Lyme borreliosis is endemic. Upon hospitalization, all patients presented erythema migrans. Isolates were typed using ribosomal DNA PCR-restriction fragment length polymorphism (RFLP) analysis of the rrfA-rrlB intergenic spacer. Of the 41 isolates typed, 37 belonged to Borrelia afzelii, 2 to Borrelia garinii, and 2 to B. burgdorferi sensu stricto. Pulsed-field gel electrophoresis, performed on 21 strains (13 new isolates and 8 controls), revealed different RFLP patterns within the B. garinii and B. afzelii strains; among the five B. garinii strains and the 12 B. afzelii strains, three or two different RFLP patterns were identified, according to the restriction enzyme used. The protein patterns of the new isolates confirmed their genotypic classification and revealed the level of expression of some immunodominant proteins like OspA and other characteristic Osps. These findings constitute the first report of such a high recovery rate of B. burgdorferi from patients in a very restricted area in Italy; they also indicate the predominance of the genospecies B. afzelii in the study area and the heterogeneity of the circulating strains.


Assuntos
Grupo Borrelia Burgdorferi/classificação , Grupo Borrelia Burgdorferi/isolamento & purificação , Doenças Endêmicas , Doença de Lyme/epidemiologia , Adulto , Proteínas de Bactérias/análise , Grupo Borrelia Burgdorferi/química , Grupo Borrelia Burgdorferi/genética , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Espaçador Ribossômico/análise , DNA Espaçador Ribossômico/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Humanos , Itália/epidemiologia , Doença de Lyme/microbiologia , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição
16.
J Vasc Surg ; 33(1): 191-4, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11137944

RESUMO

Variations in the arterial anatomy of the upper extremities, although uncommon, occur in up to one in five patients. Most of these variants occur in either the radial or ulnar artery; brachial artery variations are less common. The case we report is a rare anomaly consisting of brachial artery agenesis or regression. The brachial artery was absent from its origin but reconstituted as a normal-appearing vessel 3 cm above the antecubital fossa. The profunda brachii artery and the superior and inferior ulnar collateral arteries were also absent in this patient. The axillary artery served as the main collateral to the forearm. This constellation of anomalies has not been previously described or explained by developmental models in humans and other primates. We speculate that failure of development or arrest of specific vascular anlage in the upper extremity occurs at particular embryological stages because of unknown factors.


Assuntos
Malformações Arteriovenosas/diagnóstico por imagem , Artéria Braquial/anormalidades , Angiografia , Braço/irrigação sanguínea , Derivação Arteriovenosa Cirúrgica , Feminino , Humanos , Pessoa de Meia-Idade , Diálise Renal
18.
J Vasc Surg ; 31(3): 436-42, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10709054

RESUMO

PURPOSE: The purpose of this study was to evaluate the role and efficacy of the tourniquet in lower limb revascularization. METHODS: During a 3-year period, 195 patients underwent 205 infrainguinal reconstruction operations in the lower extremity. These patients underwent bypass with a tourniquet and inflow occlusion (group 1) or bypass without a tourniquet (group 2). The type of infrainguinal reconstruction, tourniquet ischemia time, blood loss, and complications related to tourniquet use were recorded. A subset of patients underwent serial muscle biopsies. Specimens from calf muscle were taken just (1) before application of the tourniquet, (2) before tourniquet release, and (3) once wound closure was initiated. These biopsy specimens were studied by histochemical staining and also analyzed for phosphorylase enzyme, a marker for subcellular ischemia. RESULTS: One hundred eleven patients underwent 117 infrainguinal reconstruction procedures in which the tourniquet and inflow occlusion were used. These patients were matched against 84 patients who underwent 88 infrainguinal reconstructions without the use of the tourniquet. Complete hemostatic control in group 1 was obtained in 108 of the procedures (92%). Eight percent of the procedures required minor additional techniques to obtain complete hemostasis; in two instances, the tourniquet was removed because it did not provide hemostasis. Mean tourniquet time was less than 1 hour for all reconstruction groups. There were no instances of neurologic deficit, thrombosis of distal vessels, or vascular injury that was related to the use of a tourniquet. A comparison of the two groups revealed no differences with regard to overall blood loss (P =.63) or duration of operation (P = 0.60), observations that reflect the complexity of the cases rather than the use or nonuse of a tourniquet. When tourniquet control was used, we noted a definite decrease in the time for the distal dissection, because total vascular control with extensive dissection was unnecessary. Histochemical analysis with phosphorylase revealed a conversion of tissue with active enzyme activity to a low level with tourniquet use (P <.05). CONCLUSION: The use of a tourniquet for lower limb revascularization is safe and effective and improves visualization of the operative field. Less dissection of the target vessels is required. With a combination of the nonuse of clamps and other occluding devices, we project a decrease in host hyperplastic response that will, in turn, impact favorably on patency rates. The possibility exists that early failure may be prevented by avoiding the application of traumatic forces to diseased and brittle or calcified arteries. In this study, tourniquet time had no impact on overall operative procedural time, although certain phases of the operation were clearly shortened and facilitated, particularly in complex and difficult reconstructions. Histochemical changes found in muscle biopsy specimens did not adversely impact patients clinically, but further investigation is required to elucidate subcellular events.


Assuntos
Artéria Poplítea/cirurgia , Torniquetes , Idoso , Algoritmos , Implante de Prótese Vascular , Estudos de Casos e Controles , Feminino , Humanos , Isquemia/cirurgia , Perna (Membro)/irrigação sanguínea , Masculino , Músculo Esquelético/patologia , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/patologia , Veia Safena/transplante , Fatores de Tempo
19.
Virology ; 264(2): 410-21, 1999 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-10562502

RESUMO

The small hydrophobic protein 3AB of the picornaviruses, encompassing the replication primer 3B, has been suggested to anchor the viral replication complex to membranes. For hepatitis A virus (HAV) 3AB, we have previously demonstrated its ability to form stable homodimers, to bind to membranes, and to interact specifically with RNA, implicating its multiple involvement in viral replication. In the present report, we show that HAV 3AB additionally interacts with HAV protein 3CD, a feature also described for the corresponding polypeptide of poliovirus. By assessing the interactions of three deletion mutants, distinct domains of HAV 3AB were mapped. The hydrophobic domain and the 3B moiety were found to be essential for the 3AB interaction with 3CD. Both electrostatic and hydrophobic forces are involved in this interaction. The cluster of charged amino acid residues at the C terminus of 3A seems to determine the specificity of 3AB interaction with RNA structures formed at either terminus of the HAV genome. Furthermore, our data implicate that 3A can interact with HAV RNA. Compared with poliovirus 3AB, which by itself is a nonspecific RNA-binding protein, HAV 3AB specifically recognizes HAV RNA structures that might be of relevance for initiation of viral RNA replication.


Assuntos
Cisteína Endopeptidases/metabolismo , Hepatovirus/fisiologia , RNA Viral/metabolismo , Proteínas do Core Viral/metabolismo , Proteínas Virais , Proteases Virais 3C , Sequência de Aminoácidos , Sítios de Ligação , Mapeamento Cromossômico , Cisteína Endopeptidases/genética , Dimerização , Hepatovirus/genética , Hepatovirus/metabolismo , Humanos , Dados de Sequência Molecular , Homologia de Sequência de Aminoácidos , Proteínas do Core Viral/genética
20.
Biochem Biophys Res Commun ; 249(1): 266-74, 1998 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-9705870

RESUMO

Hepatitis A virus (HAV) protein 3AB is a membrane-interacting protein containing a stretch of 21 hydrophobic amino acid residues. The nature of its membrane association was studied in detail by analysing various deletion mutants. In vivo and in vitro expression of the wild-type protein and its mutants allowed to demonstrate that the hydrophobic domain interacts with membranes and to define the portions essential for this feature. Furthermore, the results suggest that 3AB behaves as an integral membrane protein. Expression in Escherichia coli showed that 3AB can be isolated, in association with membranes, both in monomeric and in dimeric form. This finding was confirmed in vitro after post-translational incubation of the protein with microsomal membranes. Analysis of deletion mutants demonstrated that the dimerization region colocalises with the hydrophobic transmembrane domain, implicating that HAV 3AB could form oligomers mediated by the interaction of transmembrane alpha-helices.


Assuntos
Hepatovirus/metabolismo , Proteínas de Membrana/metabolismo , Proteínas do Core Viral/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Dimerização , Escherichia coli , Humanos , Proteínas de Membrana/genética , Microssomos/metabolismo , Dados de Sequência Molecular , Mutação , Proteínas do Core Viral/genética
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