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1.
Proc Natl Acad Sci U S A ; 116(34): 16750-16759, 2019 08 20.
Artigo em Inglês | MEDLINE | ID: mdl-31350352

RESUMO

In October 2017, most European countries reported unique atmospheric detections of aerosol-bound radioruthenium (106Ru). The range of concentrations varied from some tenths of µBq·m-3 to more than 150 mBq·m-3 The widespread detection at such considerable (yet innocuous) levels suggested a considerable release. To compare activity reports of airborne 106Ru with different sampling periods, concentrations were reconstructed based on the most probable plume presence duration at each location. Based on airborne concentration spreading and chemical considerations, it is possible to assume that the release occurred in the Southern Urals region (Russian Federation). The 106Ru age was estimated to be about 2 years. It exhibited highly soluble and less soluble fractions in aqueous media, high radiopurity (lack of concomitant radionuclides), and volatility between 700 and 1,000 °C, thus suggesting a release at an advanced stage in the reprocessing of nuclear fuel. The amount and isotopic characteristics of the radioruthenium release may indicate a context with the production of a large 144Ce source for a neutrino experiment.

2.
J Antimicrob Chemother ; 73(9): 2396-2399, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-29757406

RESUMO

Background: The spore is the virulence factor identified to be involved in the recurrence of the disease caused by Clostridium difficile. Objectives: To demonstrate that lethal antibiotic concentrations induce the appearance of C. difficile persister-like non-spore cells. Methods: C. difficile and derivative spo0A mutant strains were tested for their susceptibility to antibiotics, as determined using an agar dilution method. Persister-cell generation was determined for all strains using up to 10â€Š× the MIC of every antibiotic for up to 6 days. Results: Using up to 10â€Š× the MIC of every antibiotic, we were able to induce the appearance of persister-like behaviour since biphasic killing curves could be observed in response to treatment antibiotics. Conclusions: To the best of our knowledge, this work provides, for the first time, experimental evidence of the appearance of C. difficile persister-like cells, opening a new research avenue in the pathogenesis of this nosocomial pathogen.


Assuntos
Antibacterianos/farmacologia , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/crescimento & desenvolvimento , Viabilidade Microbiana/efeitos dos fármacos , Testes de Sensibilidade Microbiana
3.
Clin Exp Dermatol ; 39(3): 385-90, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24772485

RESUMO

The differences in systemic T-cell responses between patients with psoriatic arthritis (PsA) and patients with cutaneous psoriasis (Ps) are still largely unknown. To determine differential features that could be used to distinguish PsA from Ps, we compared the cytokine secretion profile of circulating T cells in patients with PsA, patients with cutaneous Ps and control subjects. We determined Th1, Th2 and Th17 cytokine secretion of anti-CD3-stimulated peripheral blood mononuclear cells (PBMCs) using a cytokine bead array. Normality of data distribution was assessed by the Shapiro-Wilk test, and statistical significance was calculated by the Mann-Whitney test. Phenotypic characterization of circulating T cells was performed by fluorescence-activated cell sorting analysis. We found that the major systemic differences distinguishing PsA from cutaneous Ps were the increased secretion of interleukin (IL)-2 by α-CD3-stimulated PBMCs and a higher percentage of circulating CD3+ T cells expressing the proliferation marker CD71 in PsA. These results indicate IL-2 as a possible biomarker of PsA, and suggest a role of circulating T cells with high proliferative capacity in the pathogenesis of PsA.


Assuntos
Artrite Psoriásica/metabolismo , Complexo CD3/imunologia , Interleucina-2/metabolismo , Leucócitos Mononucleares/metabolismo , Psoríase/metabolismo , Adolescente , Adulto , Citocinas/metabolismo , Feminino , Citometria de Fluxo , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/metabolismo , Adulto Jovem
4.
G Ital Med Lav Ergon ; 34(3 Suppl): 753-5, 2012.
Artigo em Italiano | MEDLINE | ID: mdl-23405770

RESUMO

Our study has examined the valuation of exposure to dust, noise and hand-arm vibrations (HAVs) during "extra-professional" activities of do-it-yourself, like wood smoothing, considering a group of 8 heterogeneous volunteer subjects (not expert of the sector), to find any kind of variability among the subjects. The results have shown a moderate risk for dust exposure and a realer one for HAVs, also higher noise exposure levels when an aspiration system is added to the sander. It's important that the exposure time considered in this study is not comparable to professional time exposure, cause of the "domestic" feature of this activities. Moreover, data could be influenced by different use conditions, grip and material grounds. It's also significant that there are not controls, formation and information of the subjects about the health risks, as well as ipersusceptibility.


Assuntos
Exposição Ocupacional , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
5.
Int J Immunopathol Pharmacol ; 23(3): 965-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943071

RESUMO

Treatment of patients with psoriasis and/or psoriatic arthritis and concomitant hepatitis C infection remains difficult. Except for cyclosporine, other drugs have proved unacceptable because of hepatotoxicity in patients with HCV. With the advent of anti-TNF-alpha drugs, including etanercept, new therapeutic options have become available. Our study population was five patients with psoriasis and/or psoriatic arthritis and concomitant chronic HCV infection undergoing etanercept therapy. Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and viral load were used as markers for liver damage and disease progression, respectively. The Psoriasis Area Severity Index (PASI) was used as a reference parameter for evaluating the therapeutic efficacy of etanercept therapy in improving the clinical skin picture. AST, ALT, viral load and PASI were monitored at 3-month intervals starting from the beginning of therapy up to two years after initiation of etanercept therapy. In four out of five patients, liver enzyme levels and viral load remained substantially unchanged during the course of therapy. In the one remaining patient, viral load and liver enzyme levels increased during etanercept therapy, and then decreased following the initiation of Peg-IFN/ribavirin in combination with anti-TNF-alpha therapy. PASI scores decreased in all five patients. Our data suggest that etanercept therapy is safe and provides an efficacious therapeutic alternative in patients with psoriasis and concomitant HCV infection.


Assuntos
Hepatite C/tratamento farmacológico , Imunoglobulina G/uso terapêutico , Imunossupressores/uso terapêutico , Psoríase/tratamento farmacológico , Receptores do Fator de Necrose Tumoral/uso terapêutico , Idoso , Alanina Transaminase/sangue , Antivirais/uso terapêutico , Artrite Psoriásica/complicações , Artrite Psoriásica/tratamento farmacológico , Aspartato Aminotransferases/sangue , Etanercepte , Feminino , Hepatite C/complicações , Hepatite C/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Psoríase/complicações , RNA Viral/sangue , Ribavirina/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo , Carga Viral
6.
Int J Immunopathol Pharmacol ; 22(1): 243-6, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19309573

RESUMO

Amicrobial pustulosis associated with autoimmune diseases (APAD) is a clinical entity which was described only recently and few cases are reported in the literature. This condition is characterized by recurrent acute onset with pustular lesions predominantly involving skin folds, genitals, scalp and external auditory canals of young women. The etiopathogenesis of APAD is unknown and the most effective therapeutic treatment seems to be systemic corticosteroids. We describe the case of a 16-year old female patient suffering from APAD successfully treated with cyclosporine A.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Dermatopatias Vesiculobolhosas/tratamento farmacológico , Adolescente , Feminino , Humanos
7.
J Environ Radioact ; 99(7): 1056-60, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18272267

RESUMO

The radioactivity level of soils in a volcanic area in Cameroon was determined and discussed. Thirty soils samples were collected from Buea and Limbé cities located in the south-western Cameroon. These two regions are known for theirs volcanic grounds due to the presence of Mount Cameroon Mountain. The activity concentrations of natural radionuclides as well as that of the fission product were evaluated by gamma-ray spectrometry using a hyper-purity germanium detector (HPGe). The ranges of concentrations in the surveyed soils were 11-17 Bq kg(-1), 22-36 Bq kg(-1) and 43-201 Bq kg(-1) for (226)Ra, (232)Th and (40)K, respectively. The radioisotope (137)Cs was also found but in a very small amount. The outdoor absorbed dose rate 1m above ground with the corresponding annual effective dose rate, assuming a 20% occupancy factor was estimated. The radium equivalent and the external hazard index were also evaluated and results are compared with available data from other studies and with the world average value [United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR), 1988. Sources, Effects and Risks of Ionizing Radiation. Report to the General Assembly on the Effects of Atomic Radiation. United Nations, New York; UNSCEAR, 2000. Sources and Effects of Ionizing Radiations. Report to the General Assembly with Scientific Annexes. United Nations, New York]. A solid state nuclear track detector (SSNTD), LR-115 was used for soil radon measurements at a depth of 50 cm. The ranges of soil radon concentrations were 6.7-10.8 kBq m(-3) and 5.5-8.7 kBq m(-3) in Buea and Limbé, respectively. A positive correlation was found between concentrations of radium measured with gamma-spectrometry and the soil radon concentrations measured with the nitrate cellulose detectors. The results of this study provide the radioactivity level in soil of a volcanic area, which has been found to be within the safety limits. The south-western Cameroon can be considered as having normal natural background radiation.


Assuntos
Monitoramento de Radiação/métodos , Poluentes Radioativos do Solo/análise , Erupções Vulcânicas/análise , Camarões , Geografia , Rádio (Elemento)/análise , Radônio/análise
8.
J Mol Med (Berl) ; 84(1): 97-107, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16283140

RESUMO

Glutathione (GSH) is one of the most important defense mechanisms against oxidative stress in the respiratory epithelial lining fluid. Considering that GSH secretion in respiratory cells has been postulated to be at least partially electrogenic, and that the mucoregulator S-carbocysteine lysine salt monohydrate (S-CMC-Lys) can cause an activation of epithelial Cl(-) conductance, the purpose of this study was to verify whether S-CMC-Lys is able to stimulate GSH secretion. Experiments have been performed by patch-clamp technique, by high-performance liquid chromatography (HPLC) assay, and by Western blot analysis on cultured lines of human respiratory cells (WI-26VA4 and CFT1-C2). In whole-cell configuration, after cell exposure to 100 microM S-CMC-Lys, a current due to an outward GSH flux was observed, which was inhibitable by 5-nitro-2-(3-phenylpropylamino)-benzoate and glibenclamide. This current was not observed in CFT1-C2 cells, where a functional cystic fibrosis transmembrane conductance regulator (CFTR) is lacking. Inside-out patch-clamp experiments (GSH on the cytoplasm side, Cl(-) on the extracellular side) showed the activity of a channel, which was able to conduct current in both directions: the single channel conductance was 2-4 pS, and the open probability (P(o)) was low and voltage-independent. After preincubation with 100 microM S-CMC-Lys, there was an increase in P(o), in the number of active channels present in each patch, and in the relative permeability to GSH vs Cl(-). Outwardly directed efflux of GSH could also be increased by protein kinase A, adenosine 5'-triphosphate, and cyclic adenosine monophosphate (cAMP) added to the cytoplasmic side (whole-cell configuration). The increased secretion of GSH observed in the presence of S-CMC-Lys or 8-bromoadenosine-3',5'-cyclic monophosphate was also confirmed by HPLC assay of GSH on a confluent monolayer of respiratory cells. Western blot analysis confirmed the presence of CFTR in WI-26VA4 cells. This study suggests that S-CMC-Lys is able to stimulate a channel-mediated GSH secretion by human respiratory cells: electrophysiological and pharmacological characteristics of this channel are similar to those of the CFTR channel.


Assuntos
Carbocisteína/análogos & derivados , Glutationa/metabolismo , Mucosa Respiratória/efeitos dos fármacos , Mucosa Respiratória/metabolismo , Carbocisteína/farmacologia , Linhagem Celular , Cloretos/metabolismo , Regulador de Condutância Transmembrana em Fibrose Cística/genética , Regulador de Condutância Transmembrana em Fibrose Cística/metabolismo , Humanos , Técnicas de Patch-Clamp , Mucosa Respiratória/citologia
9.
Phys Rev E Stat Nonlin Soft Matter Phys ; 75(2 Pt 1): 021115, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17358321

RESUMO

Efficient tools to characterize stochastic processes are discussed. Quantifiers originally proposed within the framework of information theory, like entropy and statistical complexity, are translated into wavelet language, which renders the above quantifiers into tools that exhibit the important "localization" advantages provided by wavelet theory. Two important and popular stochastic processes, fractional Brownian motion and fractional Gaussian noise, are studied using these wavelet-based informational tools. Exact analytical expressions are obtained for the wavelet probability distribution. Finally, numerical simulations are used to validate our analytical results.

10.
Phys Rev E Stat Nonlin Soft Matter Phys ; 76(6 Pt 1): 061114, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18233821

RESUMO

By recourse to appropriate information theory quantifiers (normalized Shannon entropy and Martín-Plastino-Rosso intensive statistical complexity measure), we revisit the characterization of Gaussian self-similar stochastic processes from a Bandt-Pompe viewpoint. We show that the ensuing approach exhibits considerable advantages with respect to other treatments. In particular, clear quantifiers gaps are found in the transition between the continuous processes and their associated noises.

11.
J Colloid Interface Sci ; 303(2): 388-403, 2006 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-16987521

RESUMO

The role of the interfacial forces was emphasized in interactive processes, involving membrane surface and penetrating molecules. The surface character controlling the dissolution process of some species (CO2, H2O, C3H6O2, C4H8O2, C5H10O2) was evaluated in relation to the supra-molecular chemistry of membranes based on 80PTMO/PA12. Infrared analyses combined with the estimation of the hydrophilic and hydrophobic domains of the membrane surface yielded useful information about the distribution, availability and accessibility of the polar moieties responsible for the penetrant sorption. At the interface, attractive Lewis acid/base interactions such as H-bonding directed the sorption of vapor species into the membranes, whereas quadrupolar CO2 participated in specific Lifshitz-van der Waals interactions with the modified polymers. In both the cases, the presence of additional polar moieties such as carbonyl, sulfonamide, and hydroxyl groups enhanced the affinity of the Pebax-based membranes for the penetrating species considered in this work. As a result, the quantification of the reactivity of a membrane surface for specific molecules may allow predictive models to be constructed and selective membranes to be designed.


Assuntos
Membranas Artificiais , Polímeros/química , 1-Butanol/química , 1-Propanol/química , Ácido Cítrico/análogos & derivados , Ácido Cítrico/química , Interações Hidrofóbicas e Hidrofílicas , Soluções/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sacarose/análogos & derivados , Sacarose/química , Sulfonamidas/química , Propriedades de Superfície , Termodinâmica
12.
J Environ Radioact ; 151 Pt 1: 264-274, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26547362

RESUMO

The radon prone areas definition is matter of many researches in radioecology, since radon is considered a leading cause of lung tumours, therefore the authorities ask for support to develop an appropriate sanitary prevention strategy. In this paper, we use geostatistical tools to elaborate a definition accounting for some of the available information about the dwellings. Co-kriging is the proper interpolator used in geostatistics to refine the predictions by using external covariates. In advance, co-kriging is not guaranteed to improve significantly the results obtained by applying the common lognormal kriging. Here, instead, such multivariate approach leads to reduce the cross-validation residual variance to an extent which is deemed as satisfying. Furthermore, with the application of Monte Carlo simulations, the paradigm provides a more conservative radon prone areas definition than the one previously made by lognormal kriging.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Habitação , Análise Espacial
13.
Artigo em Inglês | MEDLINE | ID: mdl-16089346

RESUMO

The function of the gallbladder is not only to store bile, but also to concentrate it during the interdigestive phase by means of salt-dependent water reabsorption. On the contrary, secretions of water and salt take place during the digestive phase. Dysregulation of ion absorption or secretion are common in many gallbladder diseases, such as colelithiasis. Transepithelial absorptions are determined by the Na+/K+ pump on the basolateral membrane, and by several apical membrane Na(+)-coupled transporters. Among these, some isoforms of Na+/H+ and Cl-/HCO3(-) exchangers have been studied. The presence of a Na(+)-Cl(-) simport has been molecularly and functionally characterized in some animal species. The ion transepithelial secretion is mainly dependent on an apical chloride transport attributable to a CFTR-like cAMP-activated channel with high permeability to HCO3(-). The apical membrane electrical potential is one of the factors influencing anion secretion and is maintained by the activity of cAMP-dependent K+ channels. The regulation of the activity of these channels is complex, because of their sensitivity to voltage, and to intracellular calcium and pH. The coordinated interplay underlying the regulation of transporters and channels needs to be clarified yet, as well as the interactions between transporters, channels and aquaporins.


Assuntos
Vesícula Biliar/metabolismo , Animais , Bile/metabolismo , Transporte Biológico Ativo , Proteínas de Transporte/metabolismo , Epitélio/metabolismo , Humanos , Mucosa Intestinal/metabolismo , Íons/metabolismo , Rim/metabolismo
14.
Radiat Prot Dosimetry ; 113(4): 438-41, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15788419

RESUMO

The present paper describes field performance of two different passive radon monitor devices formed, respectively, by a CR-39 track detector enclosed in a diffusion chamber and a cellulose nitrate detector (LR-115) in a heat-sealed polyethylene bag. The most important scope of these investigations was to study the performance of these detectors directly in the field. To this end, two different types of radon monitors mentioned above have been exposed simultaneously in 100 school rooms within the Italian region Friuli Venezia Giulia. Finally, the accuracy of their responses has been evaluated by exposing them under extreme humidity conditions and/or together with other radon measurement instruments.


Assuntos
Poluição do Ar em Ambientes Fechados , Colódio/química , Monitoramento de Radiação/métodos , Radiometria/métodos , Radônio/análise , Poluentes Radioativos do Ar , Difusão , Relação Dose-Resposta à Radiação , Exposição Ambiental , Itália , Plásticos , Polietileno/química , Doses de Radiação , Reprodutibilidade dos Testes , Instituições Acadêmicas
15.
J Am Osteopath Assoc ; 95(1): 31-6, 1995 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-7860366

RESUMO

During the past 2 years, an increasing number of gynecologic surgeons have performed laparoscopy-assisted vaginal hysterectomy (LAVH) and laparoscopic hysterectomy (LH). Although these procedures have become more common, they are still considered controversial. Many gynecologists question their cost, safety, efficacy, and indications. We reviewed and analyzed the perioperative and postoperative course of ten patients as well as the total cost. The patients who underwent these procedures were compared with ten matched patients who underwent abdominal hysterectomy for similar indications. Compared with control subjects, patients in the laparoscopic group had a shorter hospitalization stay (2.2 days vs 4.2 days), shorter recovery (2 weeks vs 5 weeks), and 28% fewer complications. Although the LAVH took significantly longer than TAH (3.28 hours vs 1.75 hours), the total hospital costs and charges for both procedures were similar. As technology advances and techniques are modified, the laparoscopic approach should reduce hospital costs and charges significantly. The current results suggest that LAVH may eventually be preferred to the TAH approach by physicians and their patients.


Assuntos
Análise Custo-Benefício , Histerectomia Vaginal/economia , Adulto , Análise de Variância , Estudos de Casos e Controles , Feminino , Humanos , Histerectomia Vaginal/instrumentação , Laparoscopia/economia , Resultado do Tratamento
16.
Radiat Prot Dosimetry ; 111(4): 377-83, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15550706

RESUMO

Late in the summer of 1986, the Health Physics Departments of Pordenone, Udine and Trieste, entrusted with monitoring radioactivity in the environment and food as a consequence of the Chernobyl accident, started noticing high concentrations of radionuclides--especially radiocaesium--in mushroom samples coming from different areas of the Friuli Venezia Giulia region (northeast Italy). To date, the authors have conducted 14 annual rounds of sampling and gamma spectrometry measurements on mushrooms, generating a total of over 2250 samples belonging to more than 300 species, which were picked in about 30 stations in the region. This surveys the main results from 15 years of macromycetes radiocontamination analysis in the region, the still unsolved problems, and hypotheses for future work.


Assuntos
Agaricales/química , Radioisótopos de Césio/análise , Acidente Nuclear de Chernobyl , Contaminação Radioativa de Alimentos/análise , Monitoramento de Radiação , Cinza Radioativa/análise , Medição de Risco/métodos , Análise de Alimentos/métodos , Itália , Doses de Radiação , Radiometria/métodos , Fatores de Risco , Fatores de Tempo , Topografia Médica/métodos
17.
Radiat Prot Dosimetry ; 97(4): 341-4, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11878416

RESUMO

During the year 2000 the Regional Agency for Environmental Protection (ARPA) of Friuli Venezia Giulia together with the Pordenone Province carried out a survey to determine the radon concentration in the schools. About 900 measurements have been carried out in 300 schools located both in the mountainous and in the flat territory. Moreover, geological information was gathered. both on a regional scale and, where possible, on a small detailed scale. The purpose of this study is to consider the possibility of using all the data collected to discover some radon prone areas. The first results of this study seem to locate some radon prone areas where the cover consists of very permeable gravelly deposits.


Assuntos
Poluição do Ar em Ambientes Fechados/análise , Radônio/análise , Instituições Acadêmicas , Geografia , Inquéritos Epidemiológicos , Humanos , Itália , Doses de Radiação , Monitoramento de Radiação , Radiometria
18.
Epidemiol Prev ; 12(45): 1-6, 1990 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-2151321

RESUMO

Our study was performed in 1986-'87 and 1987-'88 school years on 12.354 three to eighteen years old students (the whole scholastic population of zone 20 of Milan) in order to apply dietary education on obese subjects. Mean prevalence of obesity was 13.4% with elevated percentages in 11 to 13 years old students (17.9%), with respect to primary (14.1%), high school (12.4%) and nursery school (4.7%). The 36% of obese subjects (more than 50% of adolescents) had already tempted to reduce body weight. Intervention reduced % weight excess (from 33.6 +/- 0.5% to, 28.8 +/- 0.5% after 12 months, p less than 0.001); 67% of obese subjects lost weight and body weight returned within normal limits in 31% of subjects. An educational dietetic strategy may be successful in childhood obesity.


Assuntos
Fenômenos Fisiológicos da Nutrição Infantil , Educação em Saúde , Obesidade/prevenção & controle , Adolescente , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Itália/epidemiologia , Masculino , Obesidade/epidemiologia
19.
J Environ Radioact ; 138: 208-19, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25261867

RESUMO

Studying the geographical distribution of indoor radon concentration, using geostatistical interpolation methods, has become common for predicting and estimating the risk to the population. Here we analyse the case of Friuli Venezia Giulia (FVG), the north easternmost region of Italy. Mean value and standard deviation are, respectively, 153 Bq/m(3) and 183 Bq/m(3). The geometric mean value is 100 Bq/m(3). Spatial datasets of indoor radon concentrations are usually affected by clustering and apparent non-stationarity issues, which can eventually yield arguable results. The clustering of the present dataset seems to be non preferential. Therefore the areal estimations are not expected to be affected. Conversely, nothing can be said on the non stationarity issues and its effects. After discussing the correlation of geology with indoor radon concentration It appears they are created by the same geologic features influencing the mean and median values, and can't be eliminated via a map-based approach. To tackle these problems, in this work we deal with multiple definitions of RPA, but only in quaternary areas of FVG, using extensive simulation techniques.


Assuntos
Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Monitoramento de Radiação/métodos , Radônio/análise , Mapeamento Geográfico , Itália , Modelos Estatísticos
20.
Minerva Anestesiol ; 79(10): 1132-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23698547

RESUMO

BACKGROUND: An increase in serum lactate can occur in patients undergoing craniotomy. We hypothesized that prolonged craniotomy for brain tumor resection leads to inadequate tissue perfusion as demonstrated by increased level of lactate. This study attempts to determine the mechanism and identify any modifiable risk factors. METHODS. Prospective, observational study of 18 patients undergoing craniotomy for brain tumor resection. The primary outcome was that peak serum lactate would correlate with length of surgery. Secondary outcomes included lactate at 3, 6 and 9 hours, creatine kinase (CK) and myoglobinuria overtime. These values were correlated with expected risk factors for lactatemia including length of surgery, Body Mass Index (BMI), hypotension, hemoglobin and mannitol therapy. RESULTS. Serum lactate consistently increased in the first 3 hours in all patients (2.21±1.22 mmol/L) with a peak increase at 9 hours (3.73±1.62 mmol/L) (P<0.05 for both). The peak serum lactate did not correlate with length of surgery (P=0.799). However, the change in lactate over 3 hours (Δ3hrLactate) did correlate with BMI (P=0.010). Serum CK was increased at 12 hours (P<0.05) and reached a peak level greater than 1000 U/L in 8 of 18 patients. Six of these patients experienced myoglobinuria. No other parameters correlated with increased lactate. CONCLUSION: We observed a consistent and early increase in serum lactate in patients undergoing craniotomy, which correlated with BMI, but not length of surgery. Associated increases in CK and myoglobinuria support the hypothesis that elevated BMI contributed to muscle ischemia and tissue breakdown during craniotomy. Future studies are required to establish the overall clinical significance and mechanism of hyperlactatemia during neurosurgery.


Assuntos
Índice de Massa Corporal , Craniotomia/efeitos adversos , Ácido Láctico/sangue , Adulto , Idoso , Gasometria , Neoplasias Encefálicas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Projetos Piloto , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
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