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1.
Cell Mol Neurobiol ; 43(1): 367-380, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35061107

RESUMO

The pilocarpine-induced (PILO) model has helped elucidate the electrophysiological and molecular aspects related to mesial temporal lobe epilepsy. It has been suggested that the extensive cell death and edema observed in the brains of these animals could be induced by increased inflammatory responses, such as the rapid release of the inflammatory cytokine interleukin 1 beta (Il1b). In this study, we investigate the role of endogenous Il1b in the acute phase of the PILO model. Our aim is twofold. First, we want to determine whether it is feasible to silence Il1b in the central nervous system using a non-invasive procedure. Second, we aim to investigate the effect of silencing endogenous Il1b and its antagonist, Il1rn.We used RNA interference applied non-invasively to knockdown Il1b and its endogenous antagonist Il1rn. We found that knocking down Il1b prior to pilocarpine injection increased the mortality rate of treated animals. Furthermore, we observed that, when exposing the animals to more Il1b by silencing its endogenous antagonist Il1rn, there was a better response to status epilepticus with decreased animal mortality in the acute phase of the PILO model. Thus, we show the feasibility of using a novel, less invasive approach to study genes involved in the inflammatory response in the central nervous system. Furthermore, our results provide suggestive evidence that modulating endogenous Il1b improves animal survival in the acute phase of the PILO model and may have effects that extend into the chronic phase.


Assuntos
Epilepsia do Lobo Temporal , Epilepsia , Estado Epiléptico , Animais , Pilocarpina/efeitos adversos , Pilocarpina/metabolismo , Interleucina-1beta/metabolismo , Epilepsia/induzido quimicamente , Epilepsia/genética , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/genética , Estado Epiléptico/metabolismo , Modelos Animais de Doenças , Hipocampo/metabolismo
2.
Hum Genet ; 135(12): 1299-1327, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27699475

RESUMO

Tooth agenesis and orofacial clefts represent the most common developmental anomalies and their co-occurrence is often reported in patients as well in animal models. The aim of the present systematic review is to thoroughly investigate the current literature (PubMed, EMBASE) to identify the genes and genomic loci contributing to syndromic or non-syndromic co-occurrence of tooth agenesis and orofacial clefts, to gain insight into the molecular mechanisms underlying their dual involvement in the development of teeth and facial primordia. Altogether, 84 articles including phenotype and genotype description provided 9 genomic loci and 26 gene candidates underlying the co-occurrence of the two congenital defects: MSX1, PAX9, IRF6, TP63, KMT2D, KDM6A, SATB2, TBX22, TGFα, TGFß3, TGFßR1, TGFßR2, FGF8, FGFR1, KISS1R, WNT3, WNT5A, CDH1, CHD7, AXIN2, TWIST1, BCOR, OFD1, PTCH1, PITX2, and PVRL1. The molecular pathways, cellular functions, tissue-specific expression and disease association were investigated using publicly accessible databases (EntrezGene, UniProt, OMIM). The Gene Ontology terms of the biological processes mediated by the candidate genes were used to cluster them using the GOTermMapper (Lewis-Sigler Institute, Princeton University), speculating on six super-clusters: (a) anatomical development, (b) cell division, growth and motility, (c) cell metabolism and catabolism, (d) cell transport, (e) cell structure organization and (f) organ/system-specific processes. This review aims to increase the knowledge on the mechanisms underlying the co-occurrence of tooth agenesis and orofacial clefts, to pave the way for improving targeted (prenatal) molecular diagnosis and finally to reflect on therapeutic or ultimately preventive strategies for these disabling conditions in the future.


Assuntos
Anodontia/genética , Encéfalo/anormalidades , Fenda Labial/genética , Fissura Palatina/genética , Estudos de Associação Genética , Anodontia/fisiopatologia , Encéfalo/fisiopatologia , Fenda Labial/fisiopatologia , Fissura Palatina/fisiopatologia , Regulação da Expressão Gênica/genética , Ontologia Genética , Genótipo , Humanos , Especificidade de Órgãos , Fenótipo , Biossíntese de Proteínas/genética
3.
J Math Biol ; 71(2): 361-98, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25168624

RESUMO

This work concerns the optimization of the dose fractionation for cancer radiotherapy schedules of the kind one fraction/day, five fractions/week, assuming a fixed overall treatment time. Constraints are set to limit the radiation damages to surrounding normal tissues, as well as the daily fraction size. The response to radiation of tumour and normal tissues is represented by the classical LQ model, including the exponential repopulation term. We provide a framework to analytically determine the optimal weekly scheme of radiation doses as a function of the tumour type, the fraction upper bound and the normal tissue parameters. For a comparison with the literature, we present some numerical examples of optimal treatment schedules for specific tumour types.


Assuntos
Fracionamento da Dose de Radiação , Neoplasias/radioterapia , Biologia Computacional , Humanos , Modelos Lineares , Conceitos Matemáticos , Modelos Biológicos , Dinâmica não Linear , Planejamento da Radioterapia Assistida por Computador , Fatores de Tempo
4.
Neurol Sci ; 35 Suppl 1: 153-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24867854

RESUMO

Headache attributed to head and/or neck trauma or injury, the so-called post-traumatic headache (PTH), is the most common secondary headache disorder and one of the most controversial clinical entities in the headache field, due to its unclear pathophysiological mechanisms and the unsolved role of associated psychological and medico-legal aspects. PTH, as a significant cause of morbidity after traumatic brain injury, may occur as an isolated symptom or as one of a constellation of symptoms known as post-concussive syndrome. However, in many cases, PTH might also represent an accentuation of non-disabling, remote or infrequent pre-existing primary headaches rather than a new onset headache strictly related to the trauma. Recently, the International Classification of Headache Disorders attempted to classify PTH; however, many unsolved issues are still to be clarified. In this brief review, we will focus on PTH clinical aspects and diagnostic criteria.


Assuntos
Cefaleia Pós-Traumática/classificação , Cefaleia Pós-Traumática/fisiopatologia , Lesões Encefálicas/complicações , Lesões Encefálicas/mortalidade , Humanos , Cefaleia Pós-Traumática/diagnóstico , Cefaleia Pós-Traumática/patologia
5.
Neurol Sci ; 35 Suppl 1: 203-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24867867

RESUMO

Post-traumatic headache (PTH) is the most common secondary headache disorder, corresponding to approximately 4 % of all symptomatic headaches. PTH, a cardinal feature of the post-concussive syndrome, usually shows a phenotype similar to migraine or tension-type headache. However, rare cases of PTH similar to trigeminal autonomic cephalalgias have been described. Many studies have investigated PTH prevalence and potential risk factors for its development and maintenance. In general population, the majority of PTH patients is female and has been involved in vehicle-related accidents. Generally, headache gradually disappears over few weeks or months; however, PTH could become persistent and very disabling in a minority of patients. This brief review will focus on PTH epidemiological aspects.


Assuntos
Cefaleia Pós-Traumática/epidemiologia , Lesões Encefálicas/epidemiologia , Humanos
6.
J Environ Health ; 77(2): 22-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25226781

RESUMO

The U.S. National Shellfish Sanitation Program (NSSP) 14/43 standard states that conditionally approved shellfish growing areas must be closed for harvest when the geometric mean of fecal coliform concentration exceeds the NSSP limit of 14 most probable number (MPN)/100 mL, or the estimated 90th percentile of fecal coliform concentrations exceeds 43 MPN/100 mL for a five-tube test. The authors hypothesized that the NSSP 14/43 standard is not sufficient to protect the public from risks from consumption of biologically contaminated shellfish and the standard should be modified to 8/26 MPN/100 mL. To verify this hypothesis, the authors analyzed fecal coliform data from conditionally approved shellfish harvest areas of seven Texas bays using the Pearl sanitation model. Results showed that the shellfish closure rules mandated by the Texas Department of State Health Services actually enforced the "Pearl" limits of 8/26 MPN/100 mL, and not the NSSP limit of 14/43 MPN/100 mL.


Assuntos
Baías/microbiologia , Enterobacteriaceae/isolamento & purificação , Monitoramento Ambiental/métodos , Monitoramento Ambiental/normas , Fezes/microbiologia , Microbiologia de Alimentos/métodos , Modelos Teóricos , Frutos do Mar/microbiologia , Aquicultura , Contagem de Colônia Microbiana , Humanos , Texas
7.
Neurol Sci ; 34 Suppl 1: S47-50, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23695045

RESUMO

Migraine is a neurologic disorder characterized by disabling attacks of throbbing headache with specific features and associated symptoms. Despite the recent discoveries in basic neurosciences, migraine pathophysiology is not completely understood. Nevertheless, in the last decades, advances in functional magnetic resonance imaging (fMRI) have significantly provided new insights into migraine mechanisms. Blood oxygen level dependent (BOLD) fMRI technique is the most commonly used method to explore brain function and connectivity due to high temporal and spatial resolution. The purpose of this review is to present a synthesis of recent BOLD-fMRI studies which have allowed us to elucidate the complex process involved in migraine pathophysiology.


Assuntos
Mapeamento Encefálico/métodos , Imageamento por Ressonância Magnética/métodos , Transtornos de Enxaqueca/fisiopatologia , Circulação Cerebrovascular/fisiologia , Humanos , Oxigênio/sangue
8.
Braz J Med Biol Res ; 56: e12659, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37075347

RESUMO

Dendritic cells (DCs) are antigen-presenting cells that drive the differentiation of T CD4+ cells into different profiles according to the nature of the antigen or immunomodulator. Propolis is a resinous product made by bees that has numerous pharmacological properties, including an immunomodulatory action. To assess whether propolis can modulate the activation of CD4+ T cells by stimulating DCs with heat-labile enterotoxin B subunit (EtxB) or lipopolysaccharide (LPS), we aimed to elucidate the mechanisms affected by propolis in the differential activation of T lymphocytes. Cell viability, lymphocyte proliferation, gene expression (GATA-3 and RORc), and cytokine production (interleukin (IL)-4 and IL-17A) were analyzed. Propolis, EtxB, and LPS induced a higher lymphoproliferation compared with the control. Propolis induced GATA-3 expression and, in combination with EtxB, maintained the baseline levels. Propolis alone or in combination with LPS inhibited RORc expression. EtxB alone and in combination with propolis increased IL-4 production. Propolis in combination with LPS prevented LPS-induced IL-17A production. These results opened perspectives for the study of biological events that may be favored by propolis by promoting Th2 activation or helping in the treatment of inflammatory conditions mediated by Th17 cells.


Assuntos
Toxinas Bacterianas , Proteínas de Escherichia coli , Própole , Toxinas Bacterianas/farmacologia , Lipopolissacarídeos/farmacologia , Própole/farmacologia , Interleucina-17 , Células Th17 , Proteínas de Escherichia coli/farmacologia , Células Dendríticas , Células Th2
9.
Eur J Surg Oncol ; 49(10): 107034, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37639860

RESUMO

BACKGROUND: Differences have often been reported in the outcomes of bladder cancer (BC) patients according to gender. OBJECTIVE: This study aims to provide data on patients undergoing radical cystectomy (RC) in a high-volume tertiary urologic center and to assess whether gender discrepancies do exist in terms of surgical options and clinical outcomes. MATERIALS AND METHODS: Consecutive BC patients treated between 2016 and 2020 at a single center (Careggi University Hospital, Florence, Italy) were included in the study. The impact of gender on disease stage at diagnosis, overall survival (OS), and type of surgery was analyzed. RESULTS: The study series comprised 447 patients (85 females and 362 males). At a median follow-up of 28.3 months (IQR: 33.5), OS was 52.6% and cancer-specific survival was 67.6%. Significant differences in OS emerged for age, acute myocardial infarction (AMI), Charlson Comorbidity Index (CCI), pT, and pN. OS rates were higher in patients undergoing robot-assisted surgery and in those receiving open orthotopic neobladder (ONB) (p = 0.0001). No statistically significant differences were found between male and female patients regarding surgical offer in any age group, surgical time, early postoperative complications, pathologic stage, and OS. CONCLUSIONS: After adjustment for pathologic tumor stage and treatment modalities, female and male patients showed similar oncologic outcomes. Further studies should be undertaken to evaluate functional results in women subjected to RC.


Assuntos
Procedimentos Cirúrgicos Robóticos , Estruturas Criadas Cirurgicamente , Neoplasias da Bexiga Urinária , Humanos , Feminino , Masculino , Cistectomia/métodos , Resultado do Tratamento , Neoplasias da Bexiga Urinária/cirurgia , Neoplasias da Bexiga Urinária/patologia , Bexiga Urinária/cirurgia , Estruturas Criadas Cirurgicamente/patologia , Estudos Retrospectivos , Procedimentos Cirúrgicos Robóticos/métodos
10.
Chronobiol Int ; 39(4): 547-556, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34872434

RESUMO

Previous studies described the modifications of physiological and behavioural variables associated with self-awakening, while only few studies assessed subjective sleep quality and psychological characteristics in habitual self-awakeners. Here we investigated self-reported sleep habits and features, as well as psychological variables of habitual self-awakeners and forced-awakeners, with special regard to subjective sleep quality, personality characteristics, anxiety and depression symptoms. In our sample, the prevalence of habitual self-awakeners was 15.1%. Compared to forced-awakeners, habitual self-awakeners showed more regular sleep/wake schedules and were more frequently morning types. Moreover, habitual self-awakeners referred to be more satisfied about their sleep, to wake up more easily in the morning, to need less time to get out of bed and to feel more refreshed upon awakening than forced-awakeners. We also observed an association between the habit of self-awakening and the "ability" to set the awakening to an unusual time. Concerning psychological features, habitual self-awakeners showed higher scores in Conscientiousness and Openness and lower scores in Extraversion compared to forced-awakeners, whereas no differences between groups emerged for anxiety and depression levels. In conclusion, our findings point to an association between the habit of self-awakening and good subjective sleep quality. In this perspective, future research should objectively test in detail the effects of the self-awakening habit on sleep structure and organization, taking into account also microstructural sleep features.


Assuntos
Ritmo Circadiano , Sono , Transtornos de Ansiedade , Ritmo Circadiano/fisiologia , Extroversão Psicológica , Hábitos , Humanos , Sono/fisiologia
11.
Sleep Med ; 100: 347-353, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36191402

RESUMO

BACKGROUND: In insomnia, poor sleep is accompanied by several cognitive impairments affecting prefrontal functioning that could affect source-monitoring processes and contribute to false memories production. By using a modified version of the Deese-Roediger-McDermott paradigm (DRM), we previously found that individuals suffering from insomnia produced more false memories than good sleepers adopting a free-recall task, especially for sleep-related stimuli. However, whether poor sleep affects false memory production in a task-dependent manner (i.e., free recall or recognition) remains unclear. METHODS: Through an online research method, we adopted the classical DRM paradigm to investigate the production of false recalls and false recognitions in 32 subjects referring insomnia symptoms (IN group) and 37 good sleepers (GS group), addressing also executive functioning and source monitoring ability in both groups. RESULTS: Compared to the GS group, the IN group produced more false memories (p = .002) and intrusions (p = .004) at the free recall task and showed a lower working memory index (p = .008). No between-groups differences emerged at the recognition task. Correlational analysis revealed significant associations between DRM performance, executive functioning and source monitoring (SM) variables. Moreover, false recalls were predicted by being in the presence of insomnia symptoms (p = .012) and intrusions by the number of correct responses to the Stroop task (p = .051) and SM task (p = .015), as well as by the presence of insomnia symptoms (p = .003). CONCLUSIONS: Our data show that the presence of insomnia symptoms can influence false memories production. Furthermore, the evidence that free recall is more affected than recognition suggests that poor sleep mainly affects performance at more cognitively demanding tasks. Finally, correlational and regression analyses support the hypothesis of a link between false memories production and both the presence of insomnia symptoms and executive functioning impairments.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Humanos , Rememoração Mental/fisiologia , Reconhecimento Psicológico , Cognição , Memória de Curto Prazo
12.
Neurol Sci ; 32 Suppl 1: S165-7, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21533737

RESUMO

The aim of our study was to explore the pain processing network in patients with migraine during trigeminal nociceptive stimulation. Sixteen patients with episodic migraine without aura and 16 healthy controls performed functional magnetic resonance imaging during thermal stimuli (at 41, 51 and 53°C). Patients with migraine showed a greater activation in the perigenual part of anterior cingulate cortex at 51°C and less activation in the bilateral somatosensory cortex at 53°C compared to healthy controls. There were no differences in experimental pain perception between groups. Our findings demonstrate a functional reorganization of cerebral areas known to be involved in pain processing in patients with migraine.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiopatologia , Enxaqueca sem Aura/fisiopatologia , Vias Neurais/fisiopatologia , Dor/fisiopatologia , Adulto , Estimulação Elétrica , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Percepção da Dor/fisiologia , Nervo Trigêmeo/fisiologia
13.
G Chir ; 32(3): 110-2, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21453587

RESUMO

Antiphospholipid syndrome (APS) is an autoimmune condition characterized by vascular thromboses and/or pregnancy morbidity in the presence of antiphospholipid antibodies. The variant "catastrophic" (CAPS) is defined as a potential life-threatening disease, characterized by multiple small vessel thromboses that can lead to multiple organ failure. Surgery is between precipitating factors in CAPS International Registry, but it's still unclear the relationship between surgery and syndrome. The present study reports two surgical procedures, performed on two patients with APS admitted with diagnosis of loss of substance of the lower limb needing of reconstructive treatment. We compared and analyzed aggressive and minimally invasive surgery.


Assuntos
Síndrome Antifosfolipídica/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Índice de Gravidade de Doença , Procedimentos Cirúrgicos Operatórios/métodos
14.
Transl Psychiatry ; 11(1): 376, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34226517

RESUMO

Slowed processing speed is considered a hallmark feature of cognitive decline in cerebral small vessel disease (SVD); however, it is unclear whether SVD's association with slowed processing might be due to its association with overall declining general cognitive ability. We quantified the total MRI-visible SVD burden of 540 members of the Lothian Birth Cohort 1936 (age: 72.6 ± 0.7 years; 47% female). Using latent growth curve modelling, we tested associations between total SVD burden at mean age 73 and changes in general cognitive ability, processing speed, verbal memory and visuospatial ability, measured at age 73, 76, 79 and 82. Covariates included age, sex, vascular risk and childhood cognitive ability. In the fully adjusted models, greater SVD burden was associated with greater declines in general cognitive ability (standardised ß: -0.201; 95% CI: [-0.36, -0.04]; pFDR = 0.022) and processing speed (-0.222; [-0.40, -0.04]; pFDR = 0.022). SVD burden accounted for between 4 and 5% of variance in declines of general cognitive ability and processing speed. After accounting for the covariance between tests of processing speed and general cognitive ability, only SVD's association with greater decline in general cognitive ability remained significant, prior to FDR correction (-0.222; [-0.39, -0.06]; p = 0.008; pFDR = 0.085). Our findings do not support the notion that SVD has a specific association with declining processing speed, independent of decline in general cognitive ability (which captures the variance shared across domains of cognitive ability). The association between SVD burden and declining general cognitive ability supports the notion of SVD as a diffuse, whole-brain disease and suggests that trials monitoring SVD-related cognitive changes should consider domain-specific changes in the context of overall, general cognitive decline.


Assuntos
Doenças de Pequenos Vasos Cerebrais , Disfunção Cognitiva , Idoso , Idoso de 80 Anos ou mais , Doenças de Pequenos Vasos Cerebrais/complicações , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Criança , Cognição , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Memória
15.
Int J Food Sci ; 2019: 5782974, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31275956

RESUMO

Donkey milk can be used as a substitute for infants and children who suffer from cow milk proteins intolerance and multiple food hypersensitivity. Up to date, this is one of the main reasons why donkey milk has become a substantial area for reasearch, with an increase over the the last fifteen years. In donkey milk chain, risk analysis should be the object of particular attention because children are the main consumers of this food. In fact, this process is one of the main tool to achieve a high level of protection of human health and life; thus, the most important safety hazards should be monitored in order to attain this goal. This review focuses on the main hazards possibly present in raw donkey milk, including bacteria, fungal toxins, parasites, and chemical pollutants. Literature data have been considered, including some information that is not provided in the international literature. In the authors' opinion, the current scientific knowledge should be improved, with the aim of allowing a suitable risk assessment along the whole donkey milk chain. However, in the meantime, the competent authorithies must carry out more stringent official controls, with particular attention given to the level of primary production. The issue of a traceability system in donkey milk chain should be considered of paramount importance.

16.
J Environ Radioact ; 208-209: 106023, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31352265

RESUMO

The compartment model POSEIDON-R with an embedded dynamic food web model was used to assess 137Cs distributions in the Mediterranean and Black Seas during 1945-2020 due to the weapon testing and accident at the Chernobyl nuclear power plant. Three maximums of contamination of surface waters can be identified from 1950 in the Mediterranean Sea system. Two of them (in 1959 and 1963) were caused by atmospheric deposition due to the nuclear weapon testing. Third maximum in 1986 was related with the Chernobyl accident. Maximum of inventory of 137Cs in the Mediterranean Sea (11461 TBq) was achieved in 1968, whereas secondary maximum caused by Chernobyl accident in 1986 was almost the same (11460 TBq). The corresponding maximum in the Black Sea (3703 TBq) was reached in 1986. It is approximately two times larger than nuclear weapon tests maximum. The results of simulations conducted with generic parameters agreed well with measurements of 137Cs concentrations in the water, bottom sediments, and in marine organisms. The inventory in the Mediterranean Sea is most sensitive to the global deposition, whereas water exchange with Atlantic Ocean and the Black Sea plays minor role. The cumulative individual dose for the period 1945-2020 from consumption of marine products contaminated by 137Cs was in the range 41-130 µSv in the Mediterranean Sea and 213-274 µSv in the Black Sea. The dose increased up to 40% due to Chernobyl accident in the Mediterranean countries and 66-103% in the Black Sea countries comparatively with dose from the global deposition. A useful application of the modelling for monitoring purposes was selection of representative regions in the Mediterranean Sea (5 regions) and in the Black Sea (4 regions) using "etalon" method for classification.


Assuntos
Radioisótopos de Césio/análise , Monitoramento de Radiação , Poluentes Radioativos da Água/análise , Contaminação Radioativa da Água/estatística & dados numéricos , Mar Negro , Acidente Nuclear de Chernobyl , Modelos Teóricos
17.
Math Med Biol ; 36(1): 1-53, 2019 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-29346681

RESUMO

We address a non-linear programming problem to find the optimal scheme of dose fractionation in cancer radiotherapy. Using the LQ model to represent the response to radiation of tumour and normal tissues, we formulate a constrained non-linear optimization problem in terms of the variables number and sizes of the dose fractions. Quadratic constraints are imposed to guarantee that the damages to the early and late responding normal tissues do not exceed assigned tolerable levels. Linear constraints are set to limit the size of the daily doses. The optimal solutions are found in two steps: i) analytical determination of the optimal sizes of the fractional doses for a fixed, but arbitrary number of fractions n; ii) numerical simulation of a sequence of the previous optima for n increasing, and for specific tumour classes. We prove the existence of a finite upper bound for the optimal number of fractions. So, the optimum with respect to n is found by means of a finite number of comparisons amongst the optimal values of the objective function at the first step. In the numerical simulations, the radiosensitivity and repopulation parameters of the normal tissue are fixed, while we investigate the behaviour of the optimal solution for wide variations of the tumour parameters, relating our optima to real clinical protocols. We recognize that the optimality of hypo or equi-fractionated treatment schemes depends on the value of the tumour radiosensitivity ratio compared to the normal tissue radiosensitivity. Fast growing, radioresistant tumours may require particularly short optimal treatments.


Assuntos
Fracionamento da Dose de Radiação , Modelos Biológicos , Neoplasias/radioterapia , Neoplasias da Mama/patologia , Neoplasias da Mama/radioterapia , Proliferação de Células/efeitos da radiação , Sobrevivência Celular/efeitos da radiação , Simulação por Computador , Feminino , Humanos , Masculino , Conceitos Matemáticos , Neoplasias/patologia , Dinâmica não Linear , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Tolerância a Radiação , Planejamento da Radioterapia Assistida por Computador/estatística & dados numéricos
18.
Food Chem Toxicol ; 46(5): 1409-13, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18262709

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) were determined by high performance liquid chromatography (HPLC) method with fluorescence detection in rainbow trout fillets processed by traditional flue gas smoking and by liquid smoke flavourings, at low temperature (25 degrees C for 3h). Raw fillets were also investigated as control group. The following compounds, anthracene, fluoranthene, pyrene, benz(a)anthracene, chrysene, benzo(b)fluoranthene, benzo(k)fluoranthene and benzo(ghi)perylene were detected in all samples and no significant difference (p>0.05) was found neither between fresh and processed samples nor between the two different smoking techniques, except for chrysene and benzo(b)fluoranthene. The results show that PAHs found in rainbow trout fillets could be considered as a consequence of environmental pollution and the mild smoking process described in the present study did not affect their concentrations.


Assuntos
Manipulação de Alimentos/métodos , Carne/análise , Oncorhynchus mykiss/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Animais , Aromatizantes/química , Indicadores e Reagentes , Fumaça
19.
Travel Med Infect Dis ; 6(4): 250-2, 2008 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-18571118

RESUMO

Enterobacter sakazakii (Es) infections are likely to involve newborns and infants, causing meningitis and necrotizing enterocolitis and sepsis. Contamination of infant formulae milk during factory production or bottle preparation is implicated. Es has been isolated from environmental sources and from food other than infant formula and milk powder, but why it is associated only with the consumption of infant formulae, is unclear. According to Regulation (EC) No. 2073/2005 on the microbiological criteria for foodstuffs, Es is considered a microorganisms of greatest concern in infant formulae and follow-on formulae. Es is included between "safety criteria". The isolation of two strains of Es from 50 samples of ass' milk in Sicily is described. The antibiotic resistance profile of the isolates revealed a multiple resistance profile, including fluoroquinolones, commonly used to treat the infections. The authors underline the importance of survey because in Italy ass' milk is considered one of the solutions for infants suffering from hypersensitivity to milk protein of some animal species. There is scarce information about the ecology and the uncertainty concerning the source of infection in the children and adults; the authors are concerned that ass' milk could become a high-risk food.


Assuntos
Cronobacter sakazakii/isolamento & purificação , Equidae , Legislação sobre Alimentos , Leite/microbiologia , Segurança/legislação & jurisprudência , Animais , Antibacterianos/farmacologia , Cronobacter sakazakii/classificação , Cronobacter sakazakii/efeitos dos fármacos , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/etiologia , Infecções por Enterobacteriaceae/microbiologia , Equidae/microbiologia , Europa (Continente) , Feminino , Análise de Alimentos , Contaminação de Alimentos , Humanos , Lactente , Sicília
20.
Acta Chir Plast ; 50(2): 55-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18807392

RESUMO

Glomus tumors are benign neoplasms that differentiate from the glomus apparatus. This neoplasm is clinically characterized by a typical symptomatological triad: paroxysmal pain, pinpoint pain and hypersensitivity to cold. The diagnosis is usually clinical, but can be confirmed by instrumental tests such as X-ray, MRI, selective arteriography and most commonly by ultrasound, with or without Doppler. Surgical resection of the glomus tumor is the definitive treatment with resolution of all symptoms. From 1997 to 2007, 21 surgically-treated cases were reviewed and here we report the clinical assessment that was used. The nine most recent cases of glomus tumor underwent surgery after clinical assessment alone. In our opinion clinical examination is the most effective method to diagnose this type of tumor and in selected cases it may be sufficient to undergo surgical therapy.


Assuntos
Angiografia/métodos , Dedos , Tumor Glômico/diagnóstico , Imageamento por Ressonância Magnética/métodos , Neoplasias de Tecidos Moles/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Dedos/diagnóstico por imagem , Dedos/patologia , Seguimentos , Tumor Glômico/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias de Tecidos Moles/cirurgia , Ultrassonografia
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