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1.
Phys Med ; 104: 149-159, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36427487

RESUMO

PURPOSE: In order to translate the FLASH effect in clinical use and to treat deep tumors, Very High Electron Energy irradiations could represent a valid technique. Here, we address the main issues in the design of a VHEE FLASH machine. We present preliminary results for a compact C-band system aiming to reach a high accelerating gradient and high current necessary to deliver a Ultra High Dose Rate with a beam pulse duration of 3µs. METHODS: The proposed system is composed by low energy high current injector linac followed by a high acceleration gradient structure able to reach 60-160 MeV energy range. To obtain the maximum energy, an energy pulse compressor options is considered. CST code was used to define the specifications RF parameters of the linac. To optimize the accelerated current and therefore the delivered dose, beam dynamics simulations was performed using TSTEP and ASTRA codes. RESULTS: The VHEE parameters Linac suitable to satisfy FLASH criteria were simulated. Preliminary results allow to obtain a maximum energy of 160 MeV, with a peak current of 200 mA, which corresponds to a charge of 600 nC. CONCLUSIONS: A promising preliminary design of VHEE linac for FLASH RT has been performed. Supplementary studies are on going to complete the characterization of the machine and to manufacture and test the RF prototypes.


Assuntos
Aceleradores de Partículas
2.
Geobiology ; 15(5): 664-677, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28383164

RESUMO

Ammonium- and Fe(II)-rich fluid flows, known from deep-sea hydrothermal systems, have been extensively studied in the last decades and are considered as sites with high microbial diversity and activity. Their shallow-submarine counterparts, despite their easier accessibility, have so far been under-investigated, and as a consequence, much less is known about microbial communities inhabiting these ecosystems. A field of shallow expulsion of hydrothermal fluids has been discovered at depths of 170-400 meters off the base of the Basiluzzo Islet (Aeolian Volcanic Archipelago, Southern Tyrrhenian Sea). This area consists predominantly of both actively diffusing and inactive 1-3 meters-high structures in the form of vertical pinnacles, steeples and mounds covered by a thick orange to brown crust deposits hosting rich benthic fauna. Integrated morphological, mineralogical, and geochemical analyses revealed that, above all, these crusts are formed by ferrihydrite-type Fe3+ oxyhydroxides. Two cruises in 2013 allowed us to monitor and sampled this novel ecosystem, certainly interesting in terms of shallow-water iron-rich site. The main objective of this work was to characterize the composition of extant communities of iron microbial mats in relation to the environmental setting and the observed patterns of macrofaunal colonization. We demonstrated that iron-rich deposits contain complex and stratified microbial communities with a high proportion of prokaryotes akin to ammonium- and iron-oxidizing chemoautotrophs, belonging to Thaumarchaeota, Nitrospira, and Zetaproteobacteria. Colonizers of iron-rich mounds, while composed of the common macrobenthic grazers, predators, filter-feeders, and tube-dwellers with no representatives of vent endemic fauna, differed from the surrounding populations. Thus, it is very likely that reduced electron donors (Fe2+ and NH4+ ) are important energy sources in supporting primary production in microbial mats, which form a habitat-specific trophic base of the whole Basiluzzo hydrothermal ecosystem, including macrobenthic fauna.


Assuntos
Compostos de Amônio/metabolismo , Archaea/metabolismo , Bactérias/metabolismo , Ecossistema , Compostos Ferrosos/metabolismo , Fontes Hidrotermais/microbiologia , Ferro/metabolismo , Crescimento Quimioautotrófico , Ilhas do Mediterrâneo , Erupções Vulcânicas
3.
Pathologica ; 109(4): 418-420, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29449738

RESUMO

Sarcoidosis is a multisystemic granulomatous disease characterized by the presence of noncaseating granulomas, the exact etiology of which is yet to be determined. Most of patients show granulomas located in the lungs or in the related lymph nodes. However, lesions can affect any organ. Noncaseating granulomas are not a pathognomonic sign of sarcoidosis, being observed also in other diseases, therefore the diagnosis is often of exclusion. We report a case of sarcoidosis with parotid gland involvement in the context of a Heerfordt syndrome, discussing about its clinical presentation, pathogenesis, pathology and differential diagnosis with other granulomatous diseases.


Assuntos
Granuloma/patologia , Glândula Parótida/diagnóstico por imagem , Sarcoidose/diagnóstico por imagem , Febre Uveoparotídea/diagnóstico por imagem , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Glândula Parótida/patologia , Sarcoidose/patologia , Febre Uveoparotídea/patologia
4.
Mar Pollut Bull ; 106(1-2): 119-26, 2016 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-26992747

RESUMO

One of the main challenges of bioremediation is to define efficient protocols having a low environmental impact. We have investigated the effect of three treatments in oily-seawater after a real oil-spill occurred in the Gulf of Taranto (Italy). Biostimulation with inorganic nutrients allowed the biodegradation of the 73±2.4% of hydrocarbons, bioaugmentation with a selected hydrocarbonoclastic consortium consisting of Alcanivorax borkumensis, Alcanivorax dieselolei, Marinobacter hydrocarbonoclasticus, Cycloclasticus sp. 78-ME and Thalassolituus oleivorans degraded 79±3.2%, while the addition of nutrients and a washing agent has allowed the degradation of the 69±2.6%. On the other hand, microbial community was severely affected by the addition of the washing agent and the same product seemed to inhibit the growth of the majority of strains composing the selected consortium at the tested concentration. The use of dispersant should be accurately evaluated also considering its effect on the principal actors of biodegradation.


Assuntos
Recuperação e Remediação Ambiental/métodos , Poluição por Petróleo , Petróleo/metabolismo , Água do Mar/química , Poluentes Químicos da Água/metabolismo , Bactérias/metabolismo , Biodegradação Ambiental , Hidrocarbonetos/metabolismo , Itália , Óleos , Petróleo/análise , Poluentes Químicos da Água/análise
5.
J Appl Microbiol ; 105(5): 1694-702, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19149767

RESUMO

AIMS: In this study, we evaluated the removal efficiency of fuel hydrocarbons from a jet fuel contaminated area using bioaugmentation treatment in biopile. METHODS AND RESULTS: The hydrocarbon analysis of the sample revealed total hydrocarbons mainly constituted by benzene, toluene, ethylbenzene, xylenes (BTEX) and heavy aliphatic hydrocarbons. Enrichments of soil sample were performed with BTEX, pristane and fuel JP-5, respectively, selected hydrocarbon-degrading strains, namely Acinetobacter sp., Pseudomonas sp. and Rhodococcus sp. Three hundred litres of culture containing 10(8) cell ml(-1) of each strain and nutrients sprayed on the biopile allowed a removal of 90% of total hydrocarbons in 15 days. Bioremediation process was monitored by observation of the respiration rate and the bacterial abundance and GC-MS analysis. CONCLUSIONS: The efficiency of the treatment in the biopile was considerable. The assessment of microbial activity during the experiment is necessary for interventions targeted to improve environmental parameters such as humidity, temperature, pH and nutrients for optimization of the bioremediation process. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in biopile study improve our understanding of processes occurring during oil pollution.


Assuntos
Bactérias/metabolismo , Recuperação e Remediação Ambiental/métodos , Hidrocarbonetos/metabolismo , Microbiologia do Solo , Poluentes do Solo/metabolismo , Bactérias/crescimento & desenvolvimento , Benzeno/metabolismo , Derivados de Benzeno/metabolismo , Biodegradação Ambiental , Contagem de Colônia Microbiana/métodos , Respiração , Tolueno/metabolismo , Xilenos/metabolismo
6.
J Appl Microbiol ; 102(1): 184-94, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17184334

RESUMO

AIMS: Microcosm experiments simulating an oil spill event were performed to evaluate the response of the natural microbial community structure of Messina harbour seawater following the accidental load of petroleum. METHODS AND RESULTS: An experimental harbour seawater microcosm, supplemented with nutrients and crude oil, was monitored above 15 days in comparison with unpolluted ones (control microcosms). Bacterial cells were counted with a Live/Dead BacLight viability kit; leucine aminopeptidase, beta-glucosidase, alkaline phosphatase, lipase and esterase enzymes were measured using fluorogenic substrates. The microbial community dynamic was monitored by isolation of total RNA, RT-PCR amplification of 16S rRNA, cloning and sequencing. Oil addition stimulated an increase of the total bacterial abundance, leucine aminopeptidase and phosphatase activity rates, as well as a change in the community structure. This suggested a prompt response of micro-organisms to the load of petroleum hydrocarbons. CONCLUSIONS: The present study on the viability, specific composition and metabolic characteristics of the microbial community allows a more precise assessment of oil pollution. Both structural and functional parameters offer interesting perspectives as indicators to monitor changes caused by petroleum hydrocarbons. SIGNIFICANCE AND IMPACT OF THE STUDY: A better knowledge of microbial structural successions at oil-polluted sites is essential for environmental bioremediation. Data obtained in microcosm studies improve our understanding of natural processes occurring during oil spills.


Assuntos
Desastres , Petróleo/toxicidade , Água do Mar/microbiologia , Microbiologia da Água , Poluentes Químicos da Água/toxicidade , Alcanivoraceae/classificação , Alcanivoraceae/enzimologia , Alcanivoraceae/isolamento & purificação , Biodegradação Ambiental , Contagem de Colônia Microbiana/métodos , Processos Heterotróficos/fisiologia , Hidrocarbonetos/química , Hidrocarbonetos/toxicidade , Leucil Aminopeptidase/metabolismo , Oxigênio/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Filogenia , Proteobactérias/classificação , Proteobactérias/enzimologia , Proteobactérias/isolamento & purificação
7.
Eur J Surg Oncol ; 30(6): 618-23, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15256234

RESUMO

INTRODUCTION: Sentinel lymph node biopsy (SLNB) has been proposed as a reliable method for staging of early invasive breast cancer (EIBC). In the present study we analyse the impact of this procedure when systematically applied to all unselected women of a community-based Breast Cancer Unit (BCU). METHODS: All consecutive women with unifocal cT1-2 (

Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Biópsia de Linfonodo Sentinela/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Axila , Estudos de Viabilidade , Feminino , Humanos , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Estudos Prospectivos , Compostos Radiofarmacêuticos , Agregado de Albumina Marcado com Tecnécio Tc 99m , Tórax , Resultado do Tratamento
8.
Breast ; 13(3): 200-5, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15177422

RESUMO

The aims of this study were to analyse the feasibility and accuracy of the sentinel lymph node biopsy (SLNB) procedure as performed in a general hospital compared with the literature results; to report on the organizational aspects of planning surgical time with higher accuracy of pathological analysis; and to verify that there is a real advantage of SLNB in the surgical management of breast cancer. From October 1999 to September 2000, 371 consecutive patients with T1-2N0 breast lesions underwent SLNB. The immunoscintigraphic method of sentinel node identification was the main one used, the blue dye method being used only when the lymphoscintigraphic method was unsuccessful in identifying sentinel nodes. SLNB was done under either general or local anaesthesia, depending on how the surgical procedure was organized and clinically planned. SLNB was successful in 99% of these T1-2N0 breast cancer cases, and in 71% no metastases were found in the sentinel node. In 47% of cases with axillary metastasis only the sentinel node was involved. Nodal involvement was not present in any case of microinvasive or in situ carcinoma. In T1 cancers nodal involvement was present in 21%; in T2 cases the corresponding rate reached 51%. The results obtained with the SLNB procedure at Bergamo Hospital are similar to the literature data. When a dedicated surgical team, the nuclear medicine department and the pathology department work together, a general hospital can provide breast cancer patients with appropriate surgical treatment.


Assuntos
Neoplasias da Mama/cirurgia , Competência Clínica , Avaliação de Resultados em Cuidados de Saúde , Biópsia de Linfonodo Sentinela/normas , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Neoplasias da Mama Masculina/diagnóstico por imagem , Neoplasias da Mama Masculina/patologia , Neoplasias da Mama Masculina/cirurgia , Feminino , Hospitais Gerais , Humanos , Itália , Linfonodos/diagnóstico por imagem , Linfonodos/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Equipe de Assistência ao Paciente , Cintilografia
9.
J Endocrinol Invest ; 24(6): 423-9, 2001 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-11434666

RESUMO

Bone loss following menopause can be prevented or reduced by estrogen replacement therapy (ERT). The primary action of estrogen on bone is generally considered to be antiresorptive, but some evidence would also suggest a stimulatory effect on bone formation. The aim of this study was to assess the effect of ERT on biochemical markers of bone resorption (urinary pyridinoline and deoxypyridinoline), and of bone formation (bone-specific alkaline phosphatase--B-ALP, and the C-terminal propeptide of type I collagen--CICP) in a group of 25 postmenopausal women with no evidence of osteoporosis. Since the suggested anabolic effect of estrogen seems to take place in the early period of ERT, we measured the response of markers immediately before and after the start of treatment (30, 60, 120 and 180 days). The markers of bone resorption started to decrease at 30 days and remained low thereafter. We also observed a similar decrease in serum levels of B-ALP and CICP, reflecting a reduction of bone formation rate. Our data would indicate that ERT at the given dose does not have early anabolic effects on bone, in addition to its recognized suppressive effect on bone resorption.


Assuntos
Biomarcadores/análise , Remodelação Óssea , Terapia de Reposição de Estrogênios , Pós-Menopausa , Fosfatase Alcalina/sangue , Aminoácidos/urina , Densidade Óssea , Osso e Ossos/enzimologia , Feminino , Humanos , Interleucina-6/sangue , Pessoa de Meia-Idade , Fragmentos de Peptídeos/sangue , Pró-Colágeno/sangue , Fator de Crescimento Transformador beta/sangue
10.
Sao Paulo Med J ; 119(3): 110-3, 2001 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-11391453

RESUMO

CONTEXT: The relevance of colorectal adenocarcinoma lies in its high incidence, with the liver being the organ most frequently affected by distant metastases. Liver metastases occur in 40 to 50% of patients with colorectal adenocarcinoma, accounting for approximately 80% of deaths in the first three postoperative years. Nevertheless, despite this, they are occasionally susceptible to curative treatment. OBJECTIVE: The present investigation focused on the relationship between the level of carcinoembryonic antigen (CEA) in gallbladder bile and the presence of liver metastases secondary to colorectal adenocarcinoma. DESIGN: Diagnostic test study. SETTING: Surgical Gastroenterology Discipline at the São Paulo Hospital, São Paulo, Brazil. SAMPLE: Forty-five patients with colorectal adenocarcinoma were studied, 30 without liver metastases (group I), and 15 with liver metastases (group II). Diagnosis of liver metastases was made through computed tomography, magnetic resonance imaging and computed tomography during arterial portography. Samples of peripheral blood, portal system blood, and gallbladder bile were collected from patients during the surgical procedure. A control group composed of 18 organ donors underwent the same material collection procedures. CEA level determination was made through fluoroimmunoassay. RESULTS: Mean CEA value in peripheral serum was 2.0 ng/ml (range: 0.7 to 3.8 ng/ml) in the control group, 11.4 ng/ml (range: 0.5 to 110.3 ng/ml) in group I, and 66.0 ng/ml (range: 2.1 to 670 ng/ml) in group II. In the portal system, serum mean values found were 1.9 ng/ml (range: 0.4 to 5.0 ng/ml) in the control group, 15.3 ng/ml (range: 0.8 to 133.3 ng/ml) in group I, and 70.8 ng/ml (range: 1.8 to 725 ng/ml) in group II. Mean values found in gallbladder bile were 4.1 ng/ml (range: 1.0 to 8.6 ng/ml) in the control group, 14.3 ng/ml (range: zero to 93.0 ng/ml) in group I, and 154.8 ng/ml (range: 14.0 to 534.7 ng/ml) in group II. CONCLUSIONS: The CEA level in gallbladder bile is elevated in patients with liver metastases. Determination of CEA both in peripheral serum and in gallbladder bile enabled patients with liver metastases to be distinguished from those without such lesions. The level of CEA in gallbladder bile, however, seems to lead to a more accurate diagnosis of liver metastases secondary to colorectal adenocarcinoma.


Assuntos
Adenocarcinoma/diagnóstico , Adenocarcinoma/secundário , Bile/química , Antígeno Carcinoembrionário/análise , Neoplasias Colorretais/patologia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/secundário , Adenocarcinoma/sangue , Adulto , Idoso , Antígeno Carcinoembrionário/sangue , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Hepáticas/sangue , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade
11.
Minerva Chir ; 50(10): 871-8, 1995 Oct.
Artigo em Italiano | MEDLINE | ID: mdl-8684634

RESUMO

The diagnostic iter and treatment of peptic ulcer have evolved considerably over the past 20 years. The capillary spread of endoscopy has permitted secure and precise diagnoses to be made, in terms of both the site and size of the anatomic lesion, on the one hand, and on the other, the introduction of antisecretory drugs has led to the resolution of the majority of ulcers, so much so that the ulcer is no longer managed using strictly surgical methods but is now treated medically and only emergency cases, such as perforations, undergo surgery. Complications, such as digestive hemorrhage, penetration and stenosis, may lead to the need for surgery. In particular, perforation seems to be the only complication which has not been significantly influenced by the introduction of antisecretory therapy, the point that its status as a "complication" has been questioned leading to the suspicion of its nosological autonomy. The authors review the series of ulcer patients admitted to hospital during the period 1968 to 1991, paying special attention to the correlation with the use of antisecretory drugs which were introduced during the period 1978-1981, the trend of ulcer complications over the entire period, the duration of symptoms and the epidemiology of peptic and perforated ulcers.


Assuntos
Úlcera Duodenal/complicações , Antagonistas dos Receptores H2 da Histamina/uso terapêutico , Úlcera Péptica Perfurada/epidemiologia , Úlcera Gástrica/complicações , Idoso , Estudos de Coortes , Úlcera Duodenal/tratamento farmacológico , Feminino , Humanos , Itália/epidemiologia , Masculino , Úlcera Péptica Perfurada/cirurgia , Fatores Sexuais , Úlcera Gástrica/tratamento farmacológico
12.
Am J Clin Nutr ; 58(6): 886-90, 1993 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8249873

RESUMO

Oxidants in cigarette smoke accelerate metabolic turnover of ascorbic acid (AA), and thereby deplete body stores of this potent antioxidant and putative anticarcinogen in active smokers. We examined plasma AA concentrations and vitamin C intakes in nonsmokers regularly exposed to environmental tobacco smoke (ie, passive smokers; n = 44), as compared with active smokers (n = 47) and nonexposed nonsmokers (n = 50), to determine whether passive smokers also exhibit altered AA nutriture suggestive of oxidant exposure. Plasma AA concentrations in passive smokers were intermediate between those of active smokers (P = 0.0001) and nonexposed nonsmokers (P = 0.01) despite similar dietary vitamin C intakes. Hypovitaminosis C (< 23 mumol/L) was observed in 24% of active smokers and 12% of passive smokers but not in nonexposed nonsmokers. Reduced plasma AA concentrations were associated with low vitamin C intakes within smoke-exposed populations only. We conclude that chronic smoke exposure, particularly in association with low vitamin C intake, may reduce AA pools in both active and passive smokers.


Assuntos
Ácido Ascórbico/sangue , Poluição por Fumaça de Tabaco/efeitos adversos , Adulto , Ácido Ascórbico/administração & dosagem , Cromatografia Líquida de Alta Pressão , Estudos Transversais , Dieta , Feminino , Humanos , Pessoa de Meia-Idade , Fumar/sangue
14.
Cancer Lett ; 30(1): 11-6, 1986 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-3943077

RESUMO

The genotoxicity of cimetidine, a drug widely used in the treatment of peptic ulcer, was examined in human hepatocyte primary cultures. No induction of unscheduled DNA synthesis, as detected by autoradiography, or of DNA fragmentation, as measured by alkaline elution, was seen in metabolically competent human hepatocytes exposed for 20 h to cimetidine concentrations ranging from 0.33 to 9 mM. These findings, which are in contrast with the previously observed capability of cimetidine to induce DNA damage and repair in rat hepatocyte primary cultures, suggest that for some chemicals the rat hepatocyte model might be an inappropriate predictor of potential genotoxic effects in the analogous human cells.


Assuntos
Cimetidina/efeitos adversos , DNA/análise , Fígado/efeitos dos fármacos , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Reparo do DNA/efeitos dos fármacos , Dimetilnitrosamina/efeitos adversos , Humanos , Fígado/citologia , Fígado/metabolismo , Ratos , Especificidade da Espécie
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