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1.
AJNR Am J Neuroradiol ; 44(3): 254-260, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36797027

RESUMO

BACKGROUND AND PURPOSE: MR imaging of the brain provides unbiased neuroanatomic evaluation of brain injury and is useful for neurologic prognostication following cardiac arrest. Regional analysis of diffusion imaging may provide additional prognostic value and help reveal the neuroanatomic underpinnings of coma recovery. The purpose of this study was to evaluate global, regional, and voxelwise differences in diffusion-weighted MR imaging signal in patients in a coma after cardiac arrest. MATERIALS AND METHODS: We retrospectively analyzed diffusion MR imaging data from 81 subjects who were comatose for >48 hours following cardiac arrest. Poor outcome was defined as the inability to follow simple commands at any point during hospitalization. ADC differences between groups were evaluated across the whole brain, locally by using voxelwise analysis and regionally by using ROI-based principal component analysis. RESULTS: Subjects with poor outcome had more severe brain injury as measured by lower average whole-brain ADC (740 [SD, 102] × 10-6 mm2/s versus 833 [SD, 23] × 10-6 mm2/s, P < .001) and larger average volumes of tissue with ADC below 650 × 10-6 mms/s (464 [SD, 469] mL versus 62 [SD, 51] mL, P < .001). Voxelwise analysis showed lower ADC in the bilateral parieto-occipital areas and perirolandic cortices for the poor outcome group. ROI-based principal component analysis showed an association between lower ADC in parieto-occipital regions and poor outcome. CONCLUSIONS: Brain injury affecting the parieto-occipital region measured with quantitative ADC analysis was associated with poor outcomes after cardiac arrest. These results suggest that injury to specific brain regions may influence coma recovery.


Assuntos
Lesões Encefálicas , Traumatismos Craniocerebrais , Parada Cardíaca , Humanos , Coma/diagnóstico por imagem , Coma/etiologia , Estudos Retrospectivos , Parada Cardíaca/complicações , Parada Cardíaca/diagnóstico por imagem , Prognóstico , Encéfalo/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos , Traumatismos Craniocerebrais/complicações
2.
Eur Rev Med Pharmacol Sci ; 26(10): 3787-3796, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35647861

RESUMO

OBJECTIVE: In a prospective study, SARS-CoV-2 IgG seroprevalence was assessed during the second pandemic wave (W2) in a cohort of Inflammatory Bowel Disease (IBD) patients using biologics. The secondary aim was to compare, in the same cohort, the frequency of seropositivity and of COVID-19 during the second vs. the first (W1) wave. PATIENTS AND METHODS: From November 2020 to March 2021, SARS-CoV-2 IgG seropositivity and the prevalence of COVID-19 were assessed in a cohort of IBD patients using biologics already studied at W1. INCLUSION CRITERIA: age ≥ 18 years; diagnosis of IBD; follow-up; written consent. EXCLUSION CRITERIA: SARS-CoV-2 vaccination. Risk factors for infection, compatible symptoms, history of infection or COVID-19, nasopharyngeal swab test were recorded. Data were expressed as median [range]. The χ2 test, Student's t-test, logistic regression analysis was used. RESULTS: IBD cohort at W1 and W2 included 85 patients: 45 CD (52.9%), 40 UC (47.1%). When comparing the same 85 patients at W2 vs. W1, a higher SARS-CoV-2 seroprevalence at W2 was at the limit of the statistical significance (9.4% vs. 2.3%; p=0.05). The prevalence of COVID-19 at W2 vs. W1 was 3.5% (3/85) vs. 0% (0/85) (p=0.08). Contacts with COVID-19 patients and symptoms compatible with COVID-19 were more frequent at W2 vs. W1 (18.8 % vs. 0%; p=0.0001; 34.1% vs. 15.3%; p=0.004). At W2, history of contacts and new onset diarrhea were more frequent in seropositive patients [4/8 (50%) vs. 12/77 (15.6%); p=0.01 and 4/8 (50%) vs. 2/77 (2.6%); p=0.0001]. At W2, the risk factors for seropositivity included cough, fever, new onset diarrhea, rhinitis, arthromyalgia, dysgeusia/anosmia at univariate (p<0.05), but not at multivariate analysis. History of contacts was the only risk factor for seropositivity at univariate (p=0.03), but not at multivariate analysis (p=0.1). CONCLUSIONS: During W2, characterized by a high viral spread, IBD and biologics appeared not to increase the prevalence of SARS-CoV-2 infection or COVID-19 disease. New onset diarrhea mimicking IBD relapse may be observed in patients with SARS-CoV-2 infection.


Assuntos
Produtos Biológicos , COVID-19 , Doenças Inflamatórias Intestinais , Adolescente , Anticorpos Antivirais , Produtos Biológicos/uso terapêutico , COVID-19/epidemiologia , Vacinas contra COVID-19 , Diarreia , Humanos , Imunoglobulina G , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/epidemiologia , Recidiva Local de Neoplasia , Pandemias , Estudos Prospectivos , SARS-CoV-2 , Estudos Soroepidemiológicos
3.
Mech Ageing Dev ; 205: 111686, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35609733

RESUMO

Recent evidence demonstrates that Crocus sativus L. (saffron) counteracts oxidative stress, mitochondrial dysfunction and neuroinflammation, closely linked to initiation and progression of major brain pathologies. Interestingly, saffron constituents such as crocin, crocetin and safranal can exert antioxidant or toxic effects depending on their endogenous concentration. According to the hormesis principles, at low dose they act as antioxidants in a wide range of brain diseases by upregulating Nrf2 signaling pathway and the expression of vitagenes, such as NAD(P)H-quinone oxidoreductase (NQO1), glutathione transferase (GT), heme oxygenase-1 (HO-1), sirtuin-1 (Sirt1) and thioredoxin (Trx) system. Importantly, neuronal dysregulation of Nrf2 pathway can be a prominent cause of selective susceptibility, under neuroinflammatory conditions, due to the high vulnerability of brain cells to oxidative stress. Here we discuss natural inducers from saffron targeting Nrf2/vitagene pathway for development of new therapeutical strategies to suppress oxidative stress and neuroinflammation and consequently cognitive dysfunction. In this review we also focus on the hormetic effect of saffron active constituents, summarizing their neuroprotective and anti-neuroinflammatory properties, as well as pharmacological perspectives in brain disorders.


Assuntos
Encefalopatias , Crocus , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Humanos , Fator 2 Relacionado a NF-E2 , Oxirredução , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico
4.
Hernia ; 25(6): 1685-1692, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546474

RESUMO

PURPOSE: The advantages offered by structured reporting have already been highlighted in the literature. However, there is still no evidence on the validity of this reporting method for the study of abdominal wall defects. This study aims to show the experience of the Trentino Hernia Team (THT) multidisciplinary group in the development and use of a structured CT scan report for the study of abdominal wall defects. METHODS: A regional multidisciplinary team (THT group) used a Delphi method to identify and select the most important CT scan parameters needed to describe and stage abdominal wall defects for correct preoperative planning. Based on the selected parameters, a CT scan structured report was worked out and collectively accepted. The first 20 structured reports obtained were individually tested for compilation speed and homogeneity of the data reported by five distinct radiologists. The reports were then evaluated by five different surgeons to test the simplicity of interpretation. RESULTS: We produced a model of a structured report for the study of the abdominal wall defects and tested it in our hospital network on the first 20 reports. The average completion time was 18 min (range 12-25). There was no heterogeneity among the reported data. The reports were analysed by five distinct surgeons to evaluate completeness and simplicity of interpretation. Each surgeon used a Likert scale from 0 to 5 to evaluate each report, producing average scores of 4.8 and 4.1 for completeness and comprehensibility respectively, with a mean combined total score of 8.9 out of 10. CONCLUSIONS: Our structured report represents a fundamental tool capable of providing the surgeon with all the measurements of the parameters necessary for correct preoperative planning. At the same time, it is of crucial help for the radiologists representing an easy and fast way to report all the needed parameters using the same standards.


Assuntos
Parede Abdominal , Cirurgiões , Parede Abdominal/diagnóstico por imagem , Parede Abdominal/cirurgia , Herniorrafia , Humanos , Radiologistas , Tomografia Computadorizada por Raios X/métodos
5.
Eur Rev Med Pharmacol Sci ; 25(5): 2418-2424, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33755981

RESUMO

OBJECTIVE: Treatments used in Inflammatory Bowel Disease (IBD) have been associated with enhanced risk of viral infections and viral reactivation, however, it remains unclear whether IBD patients have increased risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. The aim of the study was to examine the prevalence of SARS-CoV-2 IgG positivity in IBD patients followed at our referral center. The role of treatments for IBD and risk factors for infection were also evaluated. PATIENTS AND METHODS: In a prospective study, all IBD patients followed at our referral centre between May 27th and July 21st, 2020 and fulfilling the inclusion criteria were tested for SARS-CoV-2 IgG. Specific IgG antibodies were evaluated by a commercial ELISA kit and SARS-CoV-2 nasopharyngeal swab was performed in seropositive patients. RESULTS: Two-hundred and eighteen patients, 128 Crohn's disease (CD) and 90 Ulcerative colitis (UC) [age 44, (19-77) years; ongoing biologics in 115 (52.7%)] were enrolled. No patient had major SARS-CoV-2-related symptoms. SARS-CoV-2 IgG were detected in 3 out of 218 (1.37%) patients with IBD (2 CD and 1 UC), all on biologics (2.6%). In all of the 3 seropositive patients, the nasopharyngeal swab was negative. There was no relationship between SARS-CoV-2 seroprevalence and the demographic/clinical characteristics of IBD patients. In contrast, history of recent travel was more frequent in the SARS-CoV-2 seropositive patients (2/3; 66.6%) than in SARS-CoV-2 seronegative patients [7/215 (3.25%); p<0.0001]. CONCLUSIONS: The prevalence of SARS-CoV-2 IgG seropositivity in IBD patients appears to be comparable to the non-IBD population and not influenced by ongoing treatments. Risk factors for infection common to the general non-IBD population should be considered when managing patients with IBD.


Assuntos
COVID-19/epidemiologia , Doenças Inflamatórias Intestinais/epidemiologia , Adulto , Idoso , Estudos de Coortes , Colite Ulcerativa/epidemiologia , Colite Ulcerativa/virologia , Doença de Crohn/epidemiologia , Doença de Crohn/virologia , Feminino , Humanos , Doenças Inflamatórias Intestinais/virologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , SARS-CoV-2/isolamento & purificação , Estudos Soroepidemiológicos
6.
Eur Rev Med Pharmacol Sci ; 24(19): 10045-10050, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33090412

RESUMO

OBJECTIVE: Crohn's Disease (CD) has been associated with non-Hodgkin lymphoma. Follicular Lymphoma (FL) limited to the liver is extremely rare, accounting for 1% to 4.4% of all Primary Hepatic Lymphoma (PHL). CASE PRESENTATION: In 2018, an 85-years old male patient with post-operative recurrence of ileal CD referred rare episodes of fever and mild diffuse abdominal pain. Since cholecystectomy in 2001, clinical history was characterized by recurrent episodes of cholangitis and common bile duct stones. In 2018, ultrasonography and MRI showed a solid focal hepatic lesion (FHL)(4.5 cm x 2.5 cm) in the IV hepatic segment. The radiographic aspect of the lesion was unusual. Initially, focal nodular hyperplasia was suspected. Clinical history of cholangitis and radiological findings subsequently suggested a diagnosis of Hepatic Abscess (HA). A progressive enlargement of the FHL (7.3 cm x 5.8 cm) despite antibiotic treatments, led to perform a liver biopsy. Histological and immunophenotypical analysis of the FHL (7.5 cm x 5.4 cm) enabled a final diagnosis of FL. The "in situ" hybridization for Epstein-Barr virus (EBER) was negative. No additional lesions related to FL were initially detected, thus suggesting a very rare case of PHL in an old patient with CD never treated with thiopurines. CONCLUSIONS: This case report highlights the need to consider a rare diagnosis of FL of the liver in patients showing a challenging focal hepatic lesion of unknown origin.


Assuntos
Doença de Crohn/diagnóstico , Neoplasias Hepáticas/diagnóstico , Linfoma Folicular/diagnóstico , Idoso de 80 Anos ou mais , Humanos , Masculino
7.
Environ Entomol ; 48(6): 1418-1424, 2019 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-31630197

RESUMO

Our purpose is to determine whether extremely low concentrations of imidacloprid (2-8 ppb) typically found in field soil 1-3 yr after a crop is grown using seed with a standard imidacloprid seed-coating could impact the fitness of whiteflies, Bemisia tabaci Gennadius (Hemiptera: Aleyrodidae). Results of our experiments indicate that imidacloprid-resistant whitefly larvae feeding on cotton seedlings growing in soil with 8.0 ppb imidacloprid are conditioned so that when the same individuals feed on plants treated with imidacloprid as adults their fitness, measured as fecundity, increases 30-70% compared with individuals that were not primed as larvae. This conditioning hormesis stimulates resistant whiteflies more than susceptible whiteflies, which may contribute to the selection of resistant populations.


Assuntos
Hemípteros , Inseticidas , Animais , Hormese , Neonicotinoides , Nitrocompostos
8.
Hum Exp Toxicol ; 38(8): 888-898, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31060383

RESUMO

During the early part of the past century, hundreds of clinical studies involving more than 37,000 patients were conducted that showed radiotherapy (RT) to be a successful and safe alternative to drug therapy for the treatment of many diverse inflammatory conditions and diseases (e.g. tendonitis, bursitis, arthritis, and serious inflammatory lung conditions). Data from these studies were collected and analyzed with the intent of estimating an optimal dosing range for RT that would induce an efficacious treatment response. RT was reported to be frequently effective after only a single treatment, with a rapid (within 24 h) and often long-lasting (from months to years) relief from symptoms. Over a two-decade span from the 1920s to the 1940s, the therapeutic responses to a single RT treatment consistently improved as the dosing for multiple ailments decreased over time to between 30 roentgen (r) and 100 r. These findings are significant and in agreement with a number of contemporary reports from Germany where RT has been commonly and successfully employed in treating ailments with an inflammatory origin. A proposed mechanism by which RT mitigates inflammation and facilitates healing is via the polarization of macrophages to an anti-inflammatory or M2 phenotype.


Assuntos
Inflamação/radioterapia , Animais , Humanos , Inflamação/imunologia , Macrófagos/imunologia , Doses de Radiação
9.
Hum Exp Toxicol ; 38(6): 746-750, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30935228

RESUMO

The topic of hormesis research funding has been a focus of deliberation within the scientific community for several decades. A common assumption/belief is that most hormesis research is funded by the private sector. With this assumption may emerge questions revolving around potential bias of such research. To provide some clarification to this issue, all hormesis research articles were obtained through online databases for 5-year increments starting with 1995 and ending with 2015 and were subsequently categorized by their funding source. A total of 710 articles were found for those years and 383 of those reported information on funding sources. Reporting funding is not required by law and until more recently was not encouraged or required by funders, research institutions, and/or scientific publishers. The analysis revealed that the assumption that the majority of hormesis research has been privately funded was not supported, with the public sector (i.e. federal and state governmental agencies) exclusively contributing to 78% of the reported research funding. Going forward, funding transparency for scientific research as a whole is essential within the scientific community as it may affect how research may be perceived, accepted, and applied.


Assuntos
Hormese , Apoio à Pesquisa como Assunto/tendências , Governo Federal , Setor Público , Governo Estadual
11.
Hum Exp Toxicol ; 37(9): 889-890, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29284298

RESUMO

In 2006, Henschler disputed the claim of Calabrese and Baldwin that Hugo Schulz should be considered the originator of the hormesis concept. Henschler cited an 1854 paper by Rudolf Virchow on the effects of two agents on the beating of cilia, which showed a hormetic-biphasic dose response. The interpretation of Henschler became broadly accepted over the past decade based on citations in the literature. However, a recent translation of the Virchow paper from German into English reveals that the claims of Henschler are not supported by the article.


Assuntos
Hormese , Relação Dose-Resposta a Droga
12.
J Neurosci Res ; 94(12): 1488-1498, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27642708

RESUMO

In the United States, 1.1-1.5% of children have been diagnosed with autism spectrum disorders (ASD), corresponding to a 30% increase in incidence and prevalence. Social and communication impairments are the main signs and symptoms of ASD, and currently available medications have been ineffective in reducing these core deficits. Observational studies have indicated that children with ASD tend to show improved cognition and behavior after febrile illness, which is associated with alteration of metabolic pathways, leading to cellular stress responses and increased expression of heat shock proteins (Hsps). Sulforaphane and hydroxytyrosol, phytochemicals derived from cruciferous vegetables and extra virgin olive oil, respectively, can induce metabolic effects in cellular stress responses that are similar to those produced by fever. Thus, modulation of endogenous cellular defense mechanisms may be an innovative approach for therapeutic intervention in ASD and other disorders associated with neuroinflammation and neurodegeneration. This Review introduces the hormetic dose-response concept and presents possible mechanisms and applications for neuroprotection. We address the emerging role of Hsps in the neuroprotective network of redox stress-responsive mechanisms and propose the potential therapeutic utility of the nutritional antioxidants sulforaphane and hydroxytyrosol against particular signs and symptoms of ASD. We argue that such research findings must be approached with pragmatism and prudence. It is vital to capitalize on recent and ongoing investments in brain science research and to refine neuroscientific knowledge and capability for more accurate diagnosis and safe, effective, and ethically sound treatment of ASD and other neuropsychiatric spectrum disorders. © 2016 Wiley Periodicals, Inc.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Homeostase , Hormese , Estresse Fisiológico , Transtorno do Espectro Autista/metabolismo , Humanos
13.
Brain Res ; 1648(Pt B): 603-616, 2016 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-26923166

RESUMO

In neurological disorders, both acute and chronic neural stress can disrupt cellular proteostasis, resulting in the generation of pathological protein. However in most cases, neurons adapt to these proteostatic perturbations by activating a range of cellular protective and repair responses, thus maintaining cell function. These interconnected adaptive mechanisms comprise a 'proteostasis network' and include the unfolded protein response, the ubiquitin proteasome system and autophagy. Interestingly, several recent studies have shown that these adaptive responses can be stimulated by preconditioning treatments, which confer resistance to a subsequent toxic challenge - the phenomenon known as hormesis. In this review we discuss the impact of adaptive stress responses stimulated in diverse human neuropathologies including Parkinson׳s disease, Wolfram syndrome, brain ischemia, and brain cancer. Further, we examine how these responses and the molecular pathways they recruit might be exploited for therapeutic gain. This article is part of a Special Issue entitled SI:ER stress.


Assuntos
Autofagia , Doenças do Sistema Nervoso , Deficiências na Proteostase/complicações , Resposta a Proteínas não Dobradas/fisiologia , Animais , Estresse do Retículo Endoplasmático/fisiologia , Humanos , Doenças do Sistema Nervoso/complicações , Doenças do Sistema Nervoso/metabolismo , Doenças do Sistema Nervoso/terapia , Complexo de Endopeptidases do Proteassoma/metabolismo , Transdução de Sinais , Ubiquitina/metabolismo
14.
Free Radic Res ; 49(5): 511-24, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25824967

RESUMO

Basal levels of oxidants are indispensible for redox signaling to produce adaptive cellular responses such as vitagenes linked to cell survival; however, at higher levels, they are detrimental to cells, contributing to aging and to the pathogenesis of numerous age-related diseases. Aging is a complex systemic process and the major gap in aging research reminds the insufficient knowledge about pathways shifting from normal "healthy" aging to disease-associated pathological aging. The major complication of normal "healthy" aging is in fact the increasing risk of age-related diseases such as cardiovascular diseases, diabetes mellitus, and neurodegenerative pathologies that can adversely affect the quality of life in general, with enhanced incidences of comorbidities and mortality. In this context, global "omics" approaches may help to dissect and fully study the cellular and molecular mechanisms of aging and age-associated processes. The proteome, being more close to the phenotype than the transcriptome and more stable than the metabolome, represents the most promising "omics" field in aging research. In the present study, we exploit recent advances in the redox biology of aging and discuss the potential of proteomics approaches as innovative tools for monitoring at the proteome level the extent of protein oxidative insult and related modifications with the identification of targeted proteins.


Assuntos
Envelhecimento/metabolismo , Estresse Oxidativo , Proteínas/análise , Proteômica , Fatores Etários , Animais , Biomarcadores/análise , Suscetibilidade a Doenças , Glutationa/análise , Glutationa/metabolismo , Humanos , Peroxidação de Lipídeos , Oxirredução , Fenótipo , Valor Preditivo dos Testes , Carbonilação Proteica , Proteínas/química , Proteínas/metabolismo , Proteômica/métodos , Fatores de Risco , Tirosina/análogos & derivados , Tirosina/metabolismo
15.
Phys Rev Lett ; 114(10): 101301, 2015 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-25815919

RESUMO

We report the results of a joint analysis of data from BICEP2/Keck Array and Planck. BICEP2 and Keck Array have observed the same approximately 400 deg^{2} patch of sky centered on RA 0 h, Dec. -57.5°. The combined maps reach a depth of 57 nK deg in Stokes Q and U in a band centered at 150 GHz. Planck has observed the full sky in polarization at seven frequencies from 30 to 353 GHz, but much less deeply in any given region (1.2 µK deg in Q and U at 143 GHz). We detect 150×353 cross-correlation in B modes at high significance. We fit the single- and cross-frequency power spectra at frequencies ≥150 GHz to a lensed-ΛCDM model that includes dust and a possible contribution from inflationary gravitational waves (as parametrized by the tensor-to-scalar ratio r), using a prior on the frequency spectral behavior of polarized dust emission from previous Planck analysis of other regions of the sky. We find strong evidence for dust and no statistically significant evidence for tensor modes. We probe various model variations and extensions, including adding a synchrotron component in combination with lower frequency data, and find that these make little difference to the r constraint. Finally, we present an alternative analysis which is similar to a map-based cleaning of the dust contribution, and show that this gives similar constraints. The final result is expressed as a likelihood curve for r, and yields an upper limit r_{0.05}<0.12 at 95% confidence. Marginalizing over dust and r, lensing B modes are detected at 7.0σ significance.

16.
J Cell Commun Signal ; 8(4): 369-84, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25381162

RESUMO

Aging process is accompanied by hormonal changes characterized by an imbalance between catabolic hormones, such as cortisol and thyroid hormones which remain stable and hormones with anabolic effects (testosterone, insulin like growth factor-1 (IGF-1) and dehydroepiandrosterone sulphate (DHEAS), that decrease with age. Deficiencies in multiple anabolic hormones have been shown to predict health status and longevity in older persons.Unlike female menopause, which is accompanied by an abrupt and permanent cessation of ovarian function (both folliculogenesis and estradiol production), male aging does not result in either cessation of testosterone production nor infertility. Although the circulating serum testosterone concentration does decline with aging, in most men this decrease is small, resulting in levels that are generally within the normal range. Hormone therapy (HT) trials have caused both apprehension and confusion about the overall risks and benefits associated with HT treatment. Stress-response hormesis from a molecular genetic perspective corresponds to the induction by stressors of an adaptive, defensive response, particularly through alteration of gene expression. Increased longevity can be associated with greater resistance to a range of stressors. During aging, a gradual decline in potency of the heat shock response occur and this may prevent repair of protein damage. Conversely, thermal stress or pharmacological agents capable of inducing stress responses, by promoting increased expression of heat-shock proteins, confer protection against denaturation of proteins and restoration of proteome function. If induction of stress resistance increases life span and hormesis induces stress resistance, hormesis most likely result in increased life span. Hormesis describes an adaptive response to continuous cellular stresses, representing a phenomenon where exposure to a mild stressor confers resistance to subsequent, otherwise harmful, conditions of increased stress. This biphasic dose-response relationship, displaying low-dose stimulation and a high-dose inhibition, as adaptive response to detrimental lifestyle factors determines the extent of protection from progression to metabolic diseases such as diabetes and more in general to hormonal dysregulation and age-related pathologies. Integrated responses exist to detect and control diverse forms of stress. This is accomplished by a complex network of the so-called longevity assurance processes, which are composed of several genes termed vitagenes. Vitagenes encode for heat shock proteins (Hsps), thioredoxin and sirtuin protein systems. Nutritional antioxidants, have recently been demonstrated to be neuroprotective through the activation of hormetic pathways under control of Vitagene protein network. Here we focus on possible signaling mechanisms involved in the activation of vitagenes resulting in enhanced defense against functional defects leading to degeneration and cell death with consequent impact on longevity processes.

17.
Hum Exp Toxicol ; 33(5): 542-53, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-23800998

RESUMO

PURPOSE: This article provides an historical assessment of the role of radiotherapy in the treatment of inner ear infections. MATERIALS AND METHODS: The research utilized a literature-based evaluation of the use of x-rays during the first half of the 20th century on the treatment of otitis media (OM), mastoiditis, and cervical adenitis and their impact on the occurrence of deafness. RESULTS: X-Rays were consistently found to be effective as a treatment modality at relatively low doses, in the range of 10-20% of the skin erythema dose, rapidly reducing inflammation, and accelerating the healing process. The mechanistic basis of the clinical successes, while addressed by contemporary researchers, is evaluated in the present article in light of current molecular biology advances, which indicate that clinically effective low doses of ionizing radiation act via the creation of an anti-inflammatory phenotype in highly inflamed tissue. CONCLUSIONS: X-Ray treatment of OM, mastoiditis, and cervical adenitis was widely accepted in the first half of the 20th century by clinicians as an effective treatment when administered within an appropriate dosage range.


Assuntos
Surdez/prevenção & controle , Otite Média/radioterapia , Surdez/etiologia , História do Século XX , Humanos , Otite Média/complicações
18.
Hum Exp Toxicol ; 32(2): 120-52, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23060412

RESUMO

This article offers a broad assessment of the hormetic dose response and its relevance to biomedical researchers, physicians, the pharmaceutical industry, and public health scientists. This article contains a series of 61 questions followed by relatively brief but referenced responses that provides support for the conclusion that hormesis is a reproducible phenomenon, commonly observed, with a frequency far greater than other dose-response models such as the threshold and linear nonthreshold dose-response models. The article provides a detailed background information on the historical foundations of hormesis, its quantitative features, mechanistic foundations, as well as how hormesis is currently being used within medicine and identifying how this concept could be further applied in the development of new therapeutic advances and in improved public health practices.


Assuntos
Relação Dose-Resposta a Droga , Hormese , Animais , Descoberta de Drogas , Saúde , Humanos , Medicina
19.
Exp Suppl ; 101: 551-64, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22945582

RESUMO

This chapter explores the historical foundations of hormesis, including the underlying reasons for its marginalization during most of the twentieth century and factors that are contributing to its resurgence and acceptance within the toxicological and pharmacological communities. Special consideration is given to the quantitative features of the hormetic dose response, as well as its capacity for generalization. Based on subsequent comparisons with other leading dose-response models, the hormesis dose response consistently provides more accurate predictions in the below threshold zone. It is expected that the hormetic dose response will become progressively more useful to the fields of toxicology, pharmacology, risk assessment, and the life sciences in general, especially where low-dose effects are of interest.


Assuntos
Hormese , Adaptação Fisiológica , Descoberta de Drogas , Humanos , Modelos Biológicos , Medição de Risco
20.
Aliment Pharmacol Ther ; 36(9): 850-7, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22971085

RESUMO

BACKGROUND: In Crohn's disease (CD), knockdown of Smad7, an inhibitor of Transforming Growth Factor (TGF)-ß1 activity, with a specific antisense oligonucleotide (GED0301) seems to be safe and tolerable and associates with TGF-ß1-mediated suppression of inflammatory pathways. AIM: Since TGF-ß1 has pro-fibrogenic effects in many organs, we evaluated whether GED0301 treatment associates with the formation of small bowel strictures. METHODS: Fifteen patients with active, inflammatory CD, receiving oral GED0301 once daily for 7 days, were monitored for the formation of small bowel strictures by Small Intestine Contrast Ultrasonography (SICUS). Serum basic fibroblast growth factor (bFGF) and human chitinase 3-like 1 (also known as YKL-40), two markers of CD-related intestinal strictures, and matrix metalloproteinases (MMP) and tissue inhibitor 1 of MMPs (TIMP1) were analysed at day 0 and day 180 by ELISA. Crohn's disease activity index (CDAI) changes were also monitored. RESULTS: Fourteen patients completed the 6-month study; the remaining underwent intestinal resection for a severe relapse not responsive to medical treatment. No patient developed small bowel stricture and none experienced obstructive symptoms during the study period. GED0301 treatment induced no significant change in the circulating levels of bFGF, YKL-40, MMPs and TIMP1. Seven of 12 patients who reached clinical remission following GED0301 treatment maintained a CDAI < 150 at day 180. CONCLUSION: Short-term treatment of patients with Crohn's disease using GED0301 is not associated with the development of small bowel stricture, thus reinforcing the concept that this drug is safe at least at early time points.


Assuntos
Doença de Crohn/tratamento farmacológico , Obstrução Intestinal/diagnóstico por imagem , Intestino Delgado/diagnóstico por imagem , Oligonucleotídeos Antissenso/uso terapêutico , Proteína Smad7/genética , Fator de Crescimento Transformador beta1/antagonistas & inibidores , Adulto , Constrição Patológica , Ensaio de Imunoadsorção Enzimática , Feminino , Humanos , Obstrução Intestinal/induzido quimicamente , Obstrução Intestinal/enzimologia , Intestino Delgado/efeitos dos fármacos , Masculino , Metaloproteinases da Matriz/metabolismo , Oligonucleotídeos Antissenso/efeitos adversos , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Fator de Crescimento Transformador beta1/administração & dosagem , Resultado do Tratamento , Ultrassonografia , Adulto Jovem
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