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1.
Artigo em Inglês | MEDLINE | ID: mdl-38624818

RESUMO

Automated valuation models (AVMs) are widely used by financial institutions to estimate the property value for a residential mortgage. The distribution of pricing errors obtained from AVMs generally show fat tails (Pender 2016; Demiroglu and James Management Science, 64(4), 1747-1760 2018). The extreme events on the tails are usually known as "black swans" (Taleb 2010) in finance and their existence complicates financial risk management, assessment, and regulation. We show via theory, Monte Carlo experiments, and an empirical example that a direct relation exists between non-normality of the pricing errors and goodness-of-fit of the house pricing models. Specifically, we provide an empirical example using US housing prices where we demonstrate an almost perfect linear relation between the estimated degrees-of-freedom for a Student's t distribution and the goodness-of-fit of sophisticated evaluation models with spatial and spatialtemporal dependence.

2.
J Biol Regul Homeost Agents ; 33(3 Suppl. 1): 1-9. DENTAL SUPPLEMENT, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31538444

RESUMO

Blood contamination of the canal during preparation and obturation can be a problem in Endodontics; this may result in apical microleakage. The purpose of this investigation was to observe and evaluate the hemostatic properties of biofilm decontaminant material (sulfonic/sulphuric acid solution, HybenX, EPIEN Medical) used in teeth with necrotic pulp and unstoppable bleeding after root canal shaping. A prospective study was designed with 2 randomized parallel groups: decontaminant material (experimental group) and sodium hypochlorite 5% (control group). The analysis of the root canal bleeding was evaluated by the clinician before and after the application of the sulfonic/sulphuric solution or sodium hypochlorite 5%, by measuring the millimeters of blood on a sterile paper point introduced in the root canal. Sixty patients with necrotic pulp and unstoppable bleeding were enrolled in this study and randomly divided into 2 groups: decontaminant material in 30 patients (experimental group) or sodium hypochlorite 5% in 30 patients (control group). T-test showed that the percentage change in millimeters of blood detected in the root canal was statistically greater for experimental group [mean difference: 0.74 (IC: 0.66-0.82); p less than 0.0001]. The hemostatic properties were better in the experimental group than in the sodium hypochlorite 5% group (control). Further research may be needed to confirm the results of this study..


Assuntos
Cavidade Pulpar , Hemorragia/prevenção & controle , Hemostáticos/uso terapêutico , Irrigantes do Canal Radicular/uso terapêutico , Humanos , Estudos Prospectivos , Tratamento do Canal Radicular , Hipoclorito de Sódio/uso terapêutico
3.
Diabet Med ; 34(12): 1684-1695, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28782842

RESUMO

AIMS: To investigate whether polycystic ovary syndrome further increases postpartum diabetes risk in women with gestational diabetes mellitus and to explore relationships between polycystic ovary syndrome and incident diabetes in women who do not develop gestational diabetes. METHODS: This retrospective cohort study (Quebec Physician Services Claims; Hospitalization Discharge Databases; Birth and Death registries) included 34 686 women with gestational diabetes during pregnancy (live birth), matched 1:1 to women without gestational diabetes by age group, year of delivery and health region. Diagnostic codes were used to define polycystic ovary syndrome and incident diabetes. Cox regression models were used to examine associations between polycystic ovary syndrome and incident diabetes. RESULTS: Polycystic ovary syndrome was present in 1.5% of women with gestational diabetes and 1.2% of women without gestational diabetes. There were more younger mothers and mothers who were not of white European ancestry among those with polycystic ovary syndrome. Those with polycystic ovary syndrome more often had a comorbidity and a lower proportion had a previous pregnancy. Polycystic ovary syndrome was associated with incident diabetes (hazard ratio 1.52; 95% CI 1.27, 1.82) among women with gestational diabetes. No conclusive associations between polycystic ovary syndrome and diabetes were identified (hazard ratio 0.94; 95% CI 0.39, 2.27) in women without gestational diabetes. CONCLUSION: In women with gestational diabetes, polycystic ovary syndrome confers additional risk for incident diabetes postpartum. In women without gestational diabetes, an association between PCOS and incident diabetes was not observed. Given the already elevated risk of diabetes in women with a history of gestational diabetes, a history of both polycystic ovary syndrome and gestational diabetes signal a critical need for diabetes surveillance and prevention.


Assuntos
Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Gestacional/epidemiologia , Síndrome do Ovário Policístico/epidemiologia , Resultado da Gravidez/epidemiologia , Adulto , Feminino , Humanos , Incidência , Recém-Nascido , Síndrome do Ovário Policístico/complicações , Gravidez , Complicações na Gravidez/epidemiologia , Quebeque/epidemiologia , História Reprodutiva , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
4.
Sci Rep ; 14(1): 2368, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38321108

RESUMO

Nature-based solutions inherently require a multifaceted perspective that encompasses diverse fields. The aim of this project is to develop more effective nature-based solutions, climate action and environmental awareness by breaking down boundaries between disciplines and fostering a co-creative process. Concepts of ecology and urban forestry were combined with the research on political ecology, environmental humanities, land art, regenerative art, performing art, participatory art, and more-than-human art. This process resulted in the creation of Aula Verde Aniene. It is located in an urban park in Rome and consists of a stand of trees arranged in circles with a specific design to give the perception of being in an outdoor vegetated room. The project activities involved community participation through art performances and citizen science initiatives. Regulating and cultural ecosystem services of Aula Verde were assessed using i-Tree Eco software and citizens' surveys. Beyond numerical descriptions of ecosystem services, the manuscript introduces shinrin-yoku as a practice to raise awareness of nature. The distinctive approach here described contributed to convey a sense of belonging to the ecosystem to citizens. The project framework and study findings have been developed to formulate policy recommendations and disseminate a format that can be adapted to diverse locations.

5.
Clin Case Rep ; 9(4): 1870-1875, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33936606

RESUMO

A case of regenerative endodontics: (a) before treatment; (b) post-treatment Xray; (c) follow-up at 6 months; (d) follow-up at 12 months.

6.
PLoS One ; 15(9): e0239572, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32960932

RESUMO

Social distancing, a non-pharmaceutical tactic aimed at reducing the spread of COVID-19, can arise because individuals voluntarily distance from others to avoid contracting the disease. Alternatively, it can arise because of jurisdictional restrictions imposed by local authorities. We run reduced form models of social distancing as a function of county-level exogenous demographic variables and jurisdictional fixed effects for 49 states to assess the relative contributions of demographic and jurisdictional effects in explaining social distancing behavior. To allow for possible spatial aspects of a contagious disease, we also model the spillovers associated with demographic variables in surrounding counties as well as allow for disturbances that depend upon those in surrounding counties. We run our models weekly and examine the evolution of the estimated coefficients over time since the onset of the COVID-19 pandemic in the United States. These estimated coefficients express the revealed preferences of individuals who were able to and chose to stay at home to avoid the disease. Stay-at-home behavior measured using cell phone tracking data exhibits considerable cross-sectional variation, increasing over nine-fold from the end of January 2020 to the end of March 2020, and then decreasing by about 50% through mid-June 2020. Our estimation results show that demographic exogenous variables explain substantially more of this variation than predictions from jurisdictional fixed effects. Moreover, the explanations from demographic exogenous variables and jurisdictional fixed effects show an evolving correlation over the sample period, initially partially offsetting, and eventually reinforcing each other. Furthermore, the predicted social distance from demographic exogenous variables shows substantial spatial autoregressive dependence, indicating clustering in social distancing behavior. The increased variance of stay-at-home behavior coupled with the high level of spatial dependence can result in relatively intense hotspots and coldspots of social distance, which has implications for disease spread and mitigation.


Assuntos
Betacoronavirus , Infecções por Coronavirus/epidemiologia , Modelos Teóricos , Pneumonia Viral/epidemiologia , Distância Psicológica , COVID-19 , Análise por Conglomerados , Infecções por Coronavirus/prevenção & controle , Estudos Transversais , Demografia , Humanos , Governo Local , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , SARS-CoV-2 , Isolamento Social , Estados Unidos
7.
J Stomatol Oral Maxillofac Surg ; 120(5): 432-442, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30641282

RESUMO

BACKGROUND: In craniofacial reconstruction, the gold standard procedure for bone regeneration is the autologous bone graft (BG). However, this procedure requiring bone harvesting is a source of morbidity. Bone substitutes, such as biphasic calcium phosphate (BCP), represent an interesting alternative but are not sufficient for bone healing in hypoplastic conditions. In such conditions, osteoprogenitors are essential to provide osteoinduction. Previous studies have shown that BCP associated with total bone marrow (TBM) provides same bone reconstruction as bone graft in a rat model of calvaria defect. Furthermore, adipose tissue stromal vascular fraction (SVF) seems to be another promising source of osteoprogenitor cells that can be used intra-operatively. This study aimed to combine, intra-operative BCP-based bone tissue engineering strategies with TBM or SVF from human sources. METHODS: 5 mm critical-size calvaria defects were performed in 18 nude rat. The defects were filled with intra-operative bone tissue engineering procedures: human BG, human TBM + BCP, human SVF + BCP and, rat TBM + BCP. Animals were sacrificed 8 weeks after implantation and calvaria were processed for histological and radiological examinations. Implanted cells were labelled with a fluorochrome. RESULTS: Micro-CT analysis revealed partial repair of bone defect. Only hBG significantly succeeded in healing the defect (43.1%). However, low rate of newly formed bone tissue was observed in all tissue engineering conditions (hTBM, hSVF, ratTBM). DISCUSSION: The lack of bone formation observed in this study could possibly be attributed to the model. CONCLUSION: This study combined with a literature analysis show the stringency of the nude rat calvaria model in term of bone regeneration.


Assuntos
Substitutos Ósseos , Engenharia Tecidual , Tecido Adiposo , Animais , Regeneração Óssea , Humanos , Osteogênese , Ratos
8.
Genes Immun ; 9(6): 501-8, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18563170

RESUMO

Cystic fibrosis pulmonary disease is characterized by excessive and prolonged inflammation. CF Pulmonary disease severity exhibits considerable variation that, to some extent, appears to be due to the presence of modifier genes. Several components of the inflammatory response are known to have altered regulation in the CF lung. Genetic variants in 52 inflammatory genes were tested for associations with lung disease indices in a CF patient population (n=737) homozygous for the DeltaF508 cystic fibrosis transmembrane conductance regulator mutation. Variants in three inflammatory genes showed significant genotypic associations with CF lung disease severity, including IL8 and previously reported TGFbeta1 (P< or =0.05). When analyzed by gender, it was apparent that IL8 variant associations were predominantly due to males. The IL8 variants were tested in an additional CF population (n=385) and the association in males verified (P< or =0.01). The IL8 variants were in strong linkage disequilibrium with each other (R2> or =0.82), while variants in neighboring genes CXCL6, RASSF6 and PF4V1 did not associate (P> or =0.26) and were in weaker LD with each other and with the IL8 variants (0.01< or =R2< or =0.49). Studies revealed differential expression between the IL8 promoter variant alleles (P<0.001). These results suggest that IL8 variants modify CF lung disease severity and have functional consequences.


Assuntos
Fibrose Cística/genética , Fibrose Cística/imunologia , Interleucina-8/genética , Feminino , Humanos , Interleucina-8/imunologia , Masculino , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Caracteres Sexuais
9.
Food Chem Toxicol ; 46(10): 3290-4, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18706466

RESUMO

The effect of elevated levels of dietary vitamin E, C and a combination of vitamin E and C (E&C) with soybean oil on activities of antioxidant (AOE) enzymes important in the protection against lipid peroxidation was studied in male rats fed with vitamin C (12 mg/g), vitamin E (3.68 mg/g) or E&C (3.68 mg/kg+12 mg/g) supplemented diets for 28 days. Catalase (CAT), glutathione peroxidase (GPx) and glutathione reductase (GR) activity in liver, pectoralis major (PM) and sartorius (S) muscles was increased significantly in rats fed with dietary vitamin C, E separately, and vitamin C&E combination, except, superoxide dismutase (SOD), which showed no alterations. These results clearly indicated that vitamin E&C separately and E&C together increased AOE activity in liver, PM and S muscle of rats. However, vitamin E and C combination enhanced AOE activity more significantly and our findings suggest the possible role of vitamin C&E and their combination in reducing the risk of chronic diseases related to oxidative stress.


Assuntos
Antioxidantes/metabolismo , Ácido Ascórbico/farmacologia , Fígado/enzimologia , Músculo Esquelético/enzimologia , Óleo de Soja/farmacologia , Vitamina E/farmacologia , Animais , Suplementos Nutricionais , Quimioterapia Combinada , Masculino , Estresse Oxidativo , Ratos , Ratos Sprague-Dawley
10.
Int Endod J ; 41(9): 800-6, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18637853

RESUMO

AIM: To present a clinical case of odontogenic keratocyst (OKC) simulating a lateral periodontal cyst. SUMMARY: A 39-year-old female complaining of swelling and pain in the left mandibular premolar area was found to have a radiolucent lesion between teeth 34 and 35 (FDI). Both teeth had incomplete root fillings, and orthograde re-treatment of both premolars was performed. At 2-year follow-up, radiographic examination showed an increase in the radiolucent defect with respect to the previous examination. A surgical treatment of tooth 34 was then performed, with histological examination of the lesion. Histological features were consistent with an OKC, and the lesion was successfully treated by complete enucleation and application of Carnoy's solution. At 2-year follow-up, no clinical signs or symptoms were found and the radiolucent area had disappeared. KEY LEARNING POINTS: Odontogenic keratocysts may mimic endodontic lesions. Clinicians should carefully review their cases and consider surgical intervention with biopsy in cases that do not heal.


Assuntos
Doenças Mandibulares/patologia , Cistos Odontogênicos/patologia , Doenças Periapicais/diagnóstico , Cisto Periodontal/diagnóstico , Adulto , Diagnóstico Diferencial , Feminino , Humanos , Queratinas , Doenças Mandibulares/diagnóstico por imagem , Doenças Mandibulares/cirurgia , Cistos Odontogênicos/diagnóstico por imagem , Cistos Odontogênicos/cirurgia , Radiografia , Tratamento do Canal Radicular
11.
J Stomatol Oral Maxillofac Surg ; 119(1): 8-15, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29033269

RESUMO

INTRODUCTION: The treatment of fractures in the mandibular condylar process remains controversial. The aim of this study was to assess the outcomes of isolated functional treatment versus open reduction and internal fixation (ORIF) of mandibular condylar fracture with articular impact based on clinical and radiological criteria. MATERIALS AND METHODS: Eighty-three patients with a mandibular condylar fracture with articular impact were included in this retrospective study. They were divided according to Loukota, Spiessl and Schroll, Mercier and Rasse, Neff, and Hlawitschka classifications. Two groups were created: operated patients (operated) and non-operated patients (non-operated). Occlusal and functional features were evaluated using clinical measurements at 1, 3, 6, and 12 months after the treatment as well as radiological measurements performed preoperatively, 6 weeks later, and at the end of the follow-up. RESULTS: A male predominance was observed in the data (69.9%, P<0.0001). Isolated functional treatment was applied in 55 patients (66.26%). Twenty-eight patients (33.7%) were operated upon using a pre-auricular or modified Risdon's approach. Maximal mouth opening (MMO) was lesser in "operated" group compared to "non-operated" group until 6 months (25.75mm vs 31.96mm, 34.76mm vs 37.95mm, 38.06mm vs 41.87mm respectively 1, 3 and, 6 months, P<0.05). Results were satisfactory 1 year after treatment (41.29mm vs 45.22mm, P>0.05). There was no difference concerning temporo-mandibular joint dysfunctions between operated and non-operated patients. For unilateral fractures, the loss of height of the ramus was significantly higher in operated patients initially compared to "non-operated" group (P=0.0137). After surgical correction, there was no difference between the two sides of mandible. At the end of the follow-up, the there was no difference between operated and non-operated ramus (P=0.1304 and 0.6420). CONCLUSION: The present study showed that a properly followed isolated functional treatment provided similar clinical results to ORIF for mandibular condylar fractures with articular impact. Surgical treatment should be preferred when the loss of height of the ramus is severe to restore the ramus height since adult condylar remodeling is less efficient than in children.


Assuntos
Fraturas Mandibulares , Adulto , Criança , Fixação Interna de Fraturas , Humanos , Masculino , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento
12.
J Tissue Eng Regen Med ; 12(5): 1238-1246, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29489057

RESUMO

Hydrogels are attractive biomaterials for replicating cellular microenvironments, but attention needs to be given to hydrogels diffusion properties. A large body of literature shows the promise of hydrogels as 3D culture models, cell expansion systems, cell delivery vehicles, and tissue constructs. Surprisingly, literature seems to have overlooked the important effects of nutrient diffusion on the viability of hydrogel-encapsulated cells. In this paper, we present the methods and results of an investigation into glucose and oxygen diffusion into a silated-hydroxypropylmethylcellulose (Si-HPMC) hydrogel. Using both an implantable glucose sensor and implantable oxygen sensor, we continuously monitored core glucose concentration and oxygen concentration at the centre of hydrogels. We demonstrated that we could tune molecular transport in Si-HPMC hydrogel by changing the polymer concentration. Specifically, the oxygen diffusion coefficient was found to significantly decrease from 3.4 × 10-10 to 2.4 × 10-10  m2  s-1 as the polymer concentration increased from 1% to 4% (w/v). Moreover, it was revealed during in vitro culture of cellularized hydrogels that oxygen depletion occurred before glucose depletion, suggesting oxygen diffusion is the major limiting factor for cell survival. Insight was also gained into the mechanism of action by which oxygen and glucose diffuse. Indeed, a direct correlation was found between the average polymer crosslinking node size and glucose parameters, and this correlation was not observed for oxygen. Overall, these experiments provide useful insights for the analysis of nutrient transport and gas exchange in hydrogels and for the development of future cellular microenvironments based on Si-HPMC or similar polysaccharide hydrogels.


Assuntos
Glucose/análise , Hidrogéis/química , Oxigênio/análise , Medicina Regenerativa , Células-Tronco/citologia , Alicerces Teciduais/química , Contagem de Células , Difusão , Humanos , Derivados da Hipromelose/química
13.
J Stomatol Oral Maxillofac Surg ; 118(5): 320-325, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28642188

RESUMO

Spontaneous regeneration of bone tissue after mandibular resection is rare in adults, although it does often take place in children. Periosteum conservation appears to play a major role in this healing process. We here report regarding a 5-year-old boy who exhibited a large mandibular trabecular juvenile ossifying fibroma. The lesion was treated by mandibulectomy, with careful preservation of the periosteal layer and immediate reconstruction with a costal graft by an intraoral approach. Monitoring over the course of a year revealed spontaneous mandibular regeneration, and it allowed for a series of measurements of the graft to be made. During this follow-up period, the mandibular height increased from 41.5% to 75.2% (P=0.0008) of the height of the unaffected mandibular height, while the width grew from 34.4% to 82.8% (P=0.0078) of the width of the healthy side, thus demonstrating the importance of a conservative approach regarding the periosteum in such situations. The costal graft acted as a support for bone regeneration by immobilizing the remaining bone fragments and by preventing soft-tissue prolapse.


Assuntos
Regeneração Óssea/fisiologia , Fibroma Ossificante/cirurgia , Regeneração Tecidual Guiada/métodos , Neoplasias Mandibulares/cirurgia , Osteotomia Mandibular , Reconstrução Mandibular/métodos , Costelas/transplante , Pré-Escolar , Fibroma Ossificante/patologia , Retalhos de Tecido Biológico/cirurgia , Retalhos de Tecido Biológico/transplante , Humanos , Masculino , Neoplasias Mandibulares/patologia , Osteotomia Mandibular/métodos , Osteotomia Mandibular/reabilitação , Tratamentos com Preservação do Órgão , Periósteo/patologia , Costelas/cirurgia
14.
J Natl Cancer Inst ; 72(3): 545-56, 1984 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-6199542

RESUMO

Normal human globulin fraction 1 (NHG-1) produced cytotoxicity and/or cytostasis as well as inhibition of protein synthesis in 8 well-characterized human tumor cell lines (4 breast cancer, 1 colon cancer, 1 melanoma, and 2 leukemia) and in 2 variants of murine B-16 melanoma. NHG-1 was not cytotoxic for the Chang liver cell line, a normal kidney embryo line, or for normal lymphocytes or macrophages when used in lower concentrations but was growth inhibitory for normal cells in higher concentrations. Although lymphocyte blastogenesis with phytohemagglutinin (PHA) was inhibited by high concentrations of NHG-1, augmentation of the lymphocyte PHA response was seen at lower concentrations, suggesting a lymphokine-like effect. Preincubation with the mitogen partially nullified these NHG-1 effects (suggesting the need for cell surface binding). Although NHG-1 antitumor activity was confirmed in selected human and murine tumor cell lines, the mechanism of its activity is unknown. Occurrence of NHG-1 in the alpha 2-globulin region (an area rich in immune-regulating factors) suggests that NHG-1 may have general "cytokine"-like effects and may be capable of regulating replication of both normal and transformed cells.


Assuntos
alfa-Globulinas/uso terapêutico , Neoplasias/fisiopatologia , Albumina Sérica/uso terapêutico , alfa-Globulinas/isolamento & purificação , Animais , Neoplasias da Mama/fisiopatologia , Agregação Celular , Linhagem Celular , Neoplasias do Colo/fisiopatologia , Replicação do DNA , Avaliação Pré-Clínica de Medicamentos , Humanos , Cinética , Leucemia Linfoide/fisiopatologia , Fígado/fisiologia , Melanoma/fisiopatologia , Camundongos , Neoplasias/terapia , Albumina Sérica/isolamento & purificação
15.
Cancer Res ; 43(9): 4504-10, 1983 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-6871879

RESUMO

The monocyte-macrophage system has long been recognized as a necessary accessory to the immune response. Recently, however, monocyte-macrophages have been shown to be important effectors of cell-mediated cellular cytotoxicity (both antibody dependent and antibody independent). In this study, monocyte-mediated cellular cytotoxicity of both types was assessed on 51Cr-labeled human erythrocytes (type B+) using autologous and standardized AB serum, and monocytes from 57 normal controls, 16 women with benign breast disease, and 175 patients with cancers of the breast (44 patients), colorectum (46 patients), head and neck (33 patients), lung (13 patients), and melanoma (39 patients). Although results were variable, many of the patients had depressed antibody-dependent cellular cytotoxicity suggesting decreased ability of their monocyte-macrophage to lyse the sensitized erythrocytes. Enhanced antibody-dependent cellular cytotoxicity was observed in patients with localized colorectal cancer, but this effect was reversed in patients with advanced disease. Serum factors did not significantly affect responses in most cases. The clinical relevance of this assay remains to be determined.


Assuntos
Citotoxicidade Celular Dependente de Anticorpos , Citotoxicidade Imunológica , Hemólise , Monócitos/imunologia , Neoplasias da Mama/imunologia , Adesão Celular , Eritrócitos/imunologia , Feminino , Neoplasias de Cabeça e Pescoço/imunologia , Humanos , Neoplasias Intestinais/imunologia , Neoplasias Pulmonares/imunologia , Macrófagos/imunologia , Melanoma/imunologia , Neoplasias/imunologia , Valores de Referência
16.
Mycotoxin Res ; 32(4): 229-236, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27637586

RESUMO

During a 5-year period from 2010 to 2014, n = 919 samples of feed and raw materials were analyzed for aflatoxin B1 (AFB1) contamination using accredited ELISA screening methods. Only 0.76 % of these samples were non-compliant with maximum levels set by the European Union Regulation 32/2002. Non-compliant samples were mainly from the province of Bari (n = 3 samples, mean AFB1 value 7.03 µg/kg), although the highest AFB1 levels were found in two samples from the provinces of Foggia and Brindisi, at 32.6 ± 3.6 µg/kg and 31.0 ± 4.0 µg/kg, respectively. Mean AFB1 levels in samples contaminated but compliant with the limits ranged from 1.4 to 2.2 µg/kg. Considering the great importance of climate conditions in mycotoxins production, during crops production and during the critical phases of materials storage and/or transport, to better understand the variability in contamination levels, the analytical results were reviewed in term of temperature and relative environmental humidity in the sampling areas. Correlations between aflatoxin B1 levels in feed and these climate factors might explain seasonal and annual variations in contamination levels. The data from the present study provide useful suggestions for the organization of targeted monitoring plans and the protection of consumers, as well as for improvement in the quality standards of zootechnological activities and feed industry.


Assuntos
Aflatoxina B1/análise , Ração Animal , Análise de Alimentos , Ensaio de Imunoadsorção Enzimática , Contaminação de Alimentos , Armazenamento de Alimentos , Umidade , Itália , Estações do Ano , Temperatura
17.
Biochim Biophys Acta ; 1503(1-2): 123-37, 2001 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-11115629

RESUMO

Results from a variety of experimental techniques which have been used to define the oxidation levels of Mn and other components in the S states of the water oxidising complex in Photosystem II are reviewed. A self-consistent interpretation of Mn X-ray absorption near edge spectroscopy, UV-visible and near infrared spectroscopic data suggests that Mn oxidation occurs only on the S0-->S1 transition, and that all four Mn centres have formal oxidation state III thereafter. Ligand oxidation occurs on the transitions to S2 and S3. This is supported by high level quantum chemical calculations and an analysis of the kinetics of substrate water exchange, as recently determined by Wydrzynski et al. (this journal). One type of model for the catalytic site structure and water oxidation mechanism, consistent with these conclusions, is discussed. This model invokes magnetically separate oxo bridged dimers with water oxidation occurring by a concerted 2H+/2e- transfer mechanism, with one H transfer to a bridge oxygen on each dimer.


Assuntos
Manganês/química , Oxigênio/química , Complexo de Proteínas do Centro de Reação Fotossintética/química , Cálcio/química , Dimerização , Microanálise por Sonda Eletrônica , Espectroscopia de Ressonância de Spin Eletrônica , Cinética , Modelos Químicos , Modelos Moleculares , Oxirredução , Complexo de Proteína do Fotossistema II , Espectrofotometria , Água/química
18.
Biochim Biophys Acta ; 1656(1): 66-77, 2004 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-15136160

RESUMO

The characteristic Mn hyperfine 'multiline' signal exhibited in the S2 state of the oxygen-evolving complex (OEC) complex of Photosystem II (PSII) has been shown to be heterogeneous in character. In this study, we have explored the effects that influence the proportions of the two forms of the S2 state multiline signal present in any sample. The narrow form of the signal is lost upon storage (weeks) at 77 K, whereas the broad form remains. In particular, we explore the roles of ethanol and methanol as well as effects of the second turnover of the enzyme on storage of the sample at 77 K. We find that in samples containing methanol, the narrow form may predominate upon the first flash, but the broad form predominates on the fifth flash and also in samples containing ethanol.


Assuntos
Etanol/química , Metanol/química , Complexo de Proteína do Fotossistema II/química , Espectroscopia de Ressonância de Spin Eletrônica , Manganês/química , Manejo de Espécimes
19.
Eur J Obstet Gynecol Reprod Biol ; 120(2): 195-7, 2005 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15925051

RESUMO

OBJECTIVE: To obtain data on the relation between age, menopause and homocysteine levels in women around menopause, we collected data for a sample of about 500 women attending a menopause clinic in Milan, Italy. STUDY DESIGN: Eligible for the study were all women aged 45-75 years, never HRT users consecutively observed for the first time at the Menopause Center of the 1st Obstetric Gynecological Clinic of the University of Milan. Fasting blood samples for total homocysteine plasma levels were collected during the visit. Of the 490 study subjects, 107 were pre-menopausal and 383 post-menopausal. RESULTS: In the total series, the mean homocysteine level was 8.3 micromol/L (S.D. 3.7, range 3.2-48.8). The values increased from 7.8 micromol/L in women aged <47 years to 9.0 micromol/L in those aged >59. Among pre-menopausal women the mean homocysteine level was 7.7 micromol/L compared to 8.3 micromol/L in post-menopausal women: this difference disappeared on the adjusted values. In post-menopausal women only, no clear relationship emerged between years since menopause and homocysteine levels. CONCLUSION: In our population, age, and not menopausal status, was the main determinant of homocysteine levels in women around menopause.


Assuntos
Envelhecimento/sangue , Homocisteína/sangue , Menopausa , Adulto , HDL-Colesterol/sangue , Feminino , Humanos , Itália , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa
20.
Cancer Epidemiol Biomarkers Prev ; 7(3): 237-41, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9521440

RESUMO

The objective of this study was to compare the use of molecular hybridization by hybrid capture methodology for human papillomavirus (HPV) with the use of demographic and lifestyle variables as intermediate triage in patients with cytological mild dyskaryosis. The study was designed as a prospective study using regression tree analysis of demographic data in consecutive patients who were subjected to colposcopic evaluation at the colposcopy clinic at the First Department of Obstetrics and Gynaecology, University of Milan (Milan, Italy). A total of 177 women were subjected to colposcopy because of a single routine Pap smear showing mild dyskaryosis. A structured interview, sampling for HPV testing for the detection of viral DNA by hybrid capture methodology, and colposcopic evaluation with cervical biopsies were performed for each subject. The accuracies of molecular hybridization for HPV and of the classification model based on the demographic and lifestyle variables in predicting patients with histologically high-grade cervical intraepithelial lesions were measured. The classification model based on the demographic and lifestyle variables showed comparable results with molecular hybridization for HPV (specificity, 0.75 versus 0.73; sensitivity, 0.61 versus 0.67, respectively). The use of demographic and lifestyle variables appears to be a simple and economic possibility for triaging patients with mild dyskaryotic smears in a screening program.


Assuntos
Sondas de DNA de HPV , Papillomaviridae , Infecções por Papillomavirus/patologia , Lesões Pré-Cancerosas/patologia , Infecções Tumorais por Vírus/patologia , Displasia do Colo do Útero/patologia , Neoplasias do Colo do Útero/patologia , Adulto , Colo do Útero/patologia , Feminino , Humanos , Estilo de Vida , Pessoa de Meia-Idade , Teste de Papanicolaou , Infecções por Papillomavirus/etiologia , Lesões Pré-Cancerosas/etiologia , Prognóstico , Fatores de Risco , Fumar/efeitos adversos , Fumar/patologia , Infecções Tumorais por Vírus/etiologia , Displasia do Colo do Útero/etiologia , Neoplasias do Colo do Útero/etiologia , Esfregaço Vaginal
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