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1.
Transl Psychiatry ; 8(1): 261, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30498214

RESUMO

Exposure to traffic-related air pollution (TRAP) is associated with a range of neurodevelopmental disorders in human populations. In rodent models, prenatal TRAP exposure increased depressive behaviors and increased brain microglial activity. To identify cellular mechanisms, we examined adult neurogenesis and the blood-brain barrier (BBB) in relation to cognition and motivated behaviors in rats that were exposed to a nano-sized TRAP subfraction from gestation into adulthood. At age 5 months, exposed male rats had 70% fewer newly generated neurons in the dentate gyrus (DG) of the hippocampus. Microglia were activated in DG and CA1 subfields (35% more Iba1). The BBB was altered, with a 75% decrease of the tight junction protein ZO-1 in the CA1 layer, and twofold more iron deposits, a marker of microhemorrhages. The exposed rats had impaired contextual memory (novel object in context), reduced food-seeking behavior, and increased depressive behaviors (forced swim). Deficits of de novo neurogenesis were inversely correlated with depressive behavior, whereas increased microbleeds were inversely correlated with deficits in contextual memory. These findings give the first evidence that prenatal and early life exposure to TRAP impairs adult hippocampal neurogenesis and increases microbleeds in association with behavioral deficits.


Assuntos
Poluentes Atmosféricos/toxicidade , Comportamento Animal , Hipocampo/fisiopatologia , Neurogênese , Efeitos Tardios da Exposição Pré-Natal/induzido quimicamente , Emissões de Veículos/toxicidade , Animais , Astrócitos/fisiologia , Barreira Hematoencefálica/metabolismo , Depressão/induzido quimicamente , Comportamento Alimentar , Feminino , Masculino , Memória , Microglia/metabolismo , Gravidez , Efeitos Tardios da Exposição Pré-Natal/fisiopatologia , Ratos Sprague-Dawley
2.
Transl Psychiatry ; 7(1): e1022, 2017 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-28140404

RESUMO

Exposure to particulate matter (PM) in the ambient air and its interactions with APOE alleles may contribute to the acceleration of brain aging and the pathogenesis of Alzheimer's disease (AD). Neurodegenerative effects of particulate air pollutants were examined in a US-wide cohort of older women from the Women's Health Initiative Memory Study (WHIMS) and in experimental mouse models. Residing in places with fine PM exceeding EPA standards increased the risks for global cognitive decline and all-cause dementia respectively by 81 and 92%, with stronger adverse effects in APOE ɛ4/4 carriers. Female EFAD transgenic mice (5xFAD+/-/human APOE ɛ3 or ɛ4+/+) with 225 h exposure to urban nanosized PM (nPM) over 15 weeks showed increased cerebral ß-amyloid by thioflavin S for fibrillary amyloid and by immunocytochemistry for Aß deposits, both exacerbated by APOE ɛ4. Moreover, nPM exposure increased Aß oligomers, caused selective atrophy of hippocampal CA1 neurites, and decreased the glutamate GluR1 subunit. Wildtype C57BL/6 female mice also showed nPM-induced CA1 atrophy and GluR1 decrease. In vitro nPM exposure of neuroblastoma cells (N2a-APP/swe) increased the pro-amyloidogenic processing of the amyloid precursor protein (APP). We suggest that airborne PM exposure promotes pathological brain aging in older women, with potentially a greater impact in ɛ4 carriers. The underlying mechanisms may involve increased cerebral Aß production and selective changes in hippocampal CA1 neurons and glutamate receptor subunits.


Assuntos
Disfunção Cognitiva/epidemiologia , Demência/epidemiologia , Exposição Ambiental/estatística & dados numéricos , Interação Gene-Ambiente , Material Particulado , Idoso , Doença de Alzheimer/epidemiologia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/efeitos dos fármacos , Peptídeos beta-Amiloides/metabolismo , Animais , Apolipoproteína E4/genética , Atrofia , Região CA1 Hipocampal/efeitos dos fármacos , Região CA1 Hipocampal/patologia , Linhagem Celular Tumoral , Cérebro/efeitos dos fármacos , Cérebro/metabolismo , Disfunção Cognitiva/genética , Demência/genética , Feminino , Humanos , Técnicas In Vitro , Camundongos , Camundongos Transgênicos , Neuritos/efeitos dos fármacos , Neuritos/patologia , Receptores de AMPA/efeitos dos fármacos , Receptores de AMPA/metabolismo
3.
Environ Monit Assess ; 188(11): 651, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27815830

RESUMO

Appropriate management and planning of suitable areas for the development of ecotourism activities can play an important role in ensuring proper use of the environment. Due to the complexity of nature, applying different tools and models-particularly multi-criteria methods-can be useful in order to achieve these goals. In this study, to indicate suitable areas (land allocation) for ecotourism activities in Taleghan county, weighted linear combination (WLC) using geographical information system (GIS), fuzzy logic, and analytical network process (ANP) were used. To compare the applicability of each of these methods in achieving the goal, the results were compared with the previous model presented by Makhdoum. The results showed that the WLC and ANP methods are more efficient than the Makhdoum model in allocating lands for recreational areas and ecotourism purposes since concomitant use of fuzzy logic and ANP for ranking and weighing the criteria provides us with more flexible and logical conditions. Furthermore, the mentioned method makes it possible to involve ecological, economic, and social criteria simultaneously in the evaluation process in order to allocate land for ecotourism purposes.


Assuntos
Conservação dos Recursos Naturais , Meio Ambiente , Recreação , Viagem , Monitoramento Ambiental/métodos , Lógica Fuzzy , Sistemas de Informação Geográfica , Humanos , Irã (Geográfico) , Modelos Teóricos
4.
Oncogenesis ; 4: e152, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26029826

RESUMO

Expression of E-cadherin has a central role in maintaining epithelial morphology. In solid tumors, reduction of E-cadherin results in disruption of intercellular contacts. Consequently, cells lose adhesive properties and gain more invasive mesenchymal properties. Nevertheless, the mechanism of E-cadherin regulation is not completely elucidated. Here we analyzed the distribution of E-cadherin expression at the cell level in human hepatocellular carcinoma, in which human liver paraffin blocks from 25 hepatocellular carcinoma patients were prepared from cancerous (CA) and noncancerous areas (NCA). In situ hybridization (ISH) was performed to detect E-cadherin and hypoxia-induced factor-1α (HIF1α) mRNAs and immunohistochemistry to stain E-cadherin protein. In parallel, RNA was extracted from CA and NCA, and E-cadherin and HIF1α were quantified by quantitative reverse transcription PCR. ISH revealed abundant E-cadherin mRNA in nuclei of hepatocellular carcinoma cells (HCCs), whereas immunohistochemistry showed depletion of E-cadherin protein from these areas. In sections of NCA, E-cadherin mRNA was also found in the cytosol, and E-cadherin protein was detected on the membrane of cells. Experiments in cell lines confirmed E-cadherin mRNA in nuclei of cells negative for E-cadherin protein. HIF1α expression is elevated in CAs, which is associated with a clear cytosolic staining for this mRNA. Our results demonstrate that E-caderhin mRNA is selectively retained in nuclei of HCCs, whereas other mRNAs are still exported, suggesting that translocation of E-cadherin mRNA from nuclei to cytoplasm has a role in regulating E-cadherin protein levels during epithelial mesenchymal transition.

5.
Int J Comput Assist Radiol Surg ; 10(6): 749-59, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25847671

RESUMO

PURPOSE: Malignant neoplasms of the liver are among the most frequent cancers worldwide. Given the diversity of options for liver cancer therapy, the choice of treatment depends on various parameters including patient condition, tumor size and location, liver function, and previous interventions. To address this issue, we present the first approach to treatment strategy planning based on holistic processing of patient-individual data, practical knowledge (i.e., case knowledge), and factual knowledge (e.g., clinical guidelines and studies). METHODS: The contributions of this paper are as follows: (1) a formalized dynamic patient model that incorporates all the heterogeneous data acquired for a specific patient in the whole course of disease treatment; (2) a concept for formalizing factual knowledge; and (3) a technical infrastructure that enables storing, accessing, and processing of heterogeneous data to support clinical decision making. RESULTS: Our patient model, which currently covers 602 patient-individual parameters, was successfully instantiated for 184 patients. It was sufficiently comprehensive to serve as the basis for the formalization of a total of 72 rules extracted from studies on patients with colorectal liver metastases or hepatocellular carcinoma. For a subset of 70 patients with these diagnoses, the system derived an average of [Formula: see text] assertions per patient. CONCLUSION: The proposed concept paves the way for holistic treatment strategy planning by enabling joint storing and processing of heterogeneous data from various information sources.


Assuntos
Carcinoma Hepatocelular/cirurgia , Tomada de Decisão Clínica , Neoplasias Colorretais/cirurgia , Neoplasias Hepáticas/cirurgia , Fígado/cirurgia , Modelos Anatômicos , Carcinoma Hepatocelular/secundário , Neoplasias Colorretais/secundário , Humanos , Neoplasias Hepáticas/patologia
6.
Int J Comput Assist Radiol Surg ; 9(5): 759-68, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24664266

RESUMO

PURPOSE: Ultrasound (US) guided procedures are frequently performed for diagnosis and treatment of many diseases. However, there are safety and procedure duration limitations in US-guided interventions due to poor image quality and inadequate visibility of medical instruments in the field of view. To address this issue, we propose an interventional imaging system based on a mobile electromagnetic (EM) field generator (FG) attached to a US probe. METHODS: A standard US probe was integrated with an EM FG to allow combined movement of the FG with real-time imaging to achieve (1) increased tracking accuracy for medical instruments are located near the center of the tracking volume, (2) increased robustness because the FG is distant to large metallic objects, and (3) reduced setup complexity since time-consuming placement of the FG is not required. The new integrated US-FG imaging system was evaluated by assessing tracking and calibration accuracy in a clinical setting. To demonstrate clinical applicability, the prototype US-EMFG probe was tested in needle puncture procedures. RESULTS: The mobile EMFG attached to a US probe yielded sub-millimeter tracking accuracy despite the presence of metal close to the FG. Calibration errors were in the range of 1-2 mm. In an initial phantom study on US-guided needle punctures, targeting errors of about 3 mm were achieved. CONCLUSION: A combined US-EMFG probe is feasible and effective for tracking medical instruments relative to US images with high accuracy and robustness while keeping hardware complexity low.


Assuntos
Campos Eletromagnéticos , Imagens de Fantasmas , Ultrassonografia de Intervenção/métodos , Calibragem , Humanos
7.
J Laryngol Otol ; 123(10): 1150-4, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19573255

RESUMO

OBJECTIVE: Sulphur mustard is a chemical warfare agent which was used against Iranian combatants and civilians between 1983 and 1988. The purpose of this study was to document the delayed toxic effects of sulphur mustard in Iranian veterans, focussing on head and neck complications. PATIENTS AND METHODS: This was a two-year, prospective, descriptive study of 43 male Iranian veterans aged 34 to 48 years (mean 41.8 years) who were moderately disabled or worse due to sulphur mustard poisoning. Investigations were performed with consent, including haematological, biochemical and immunological tests, spirometry, chest X-ray, high resolution computed tomography of the lungs, and skin biopsies. Further investigations and interventions were performed as clinically indicated. RESULTS: The most affected sites were the lungs (95 per cent), peripheral nerves (77 per cent), skin (73 per cent), eyes (68 per cent), and head and neck (16.2 per cent). Of seven patients with mostly head and neck complications, four had a skin disorder (hyperpigmentation in all four, an erythematous, papular rash in two, and dry skin in one). Two patients had thyroid cancer (undifferentiated thyroid carcinoma in one and papillary carcinoma of a thyroglossal cyst in the other, 12 and 14 years after sulphur mustard exposure, respectively). One patient had nasopharyngeal carcinoma, 12 years after sulphur mustard exposure. CONCLUSION: Carcinomas of the thyroid and nasopharynx in three patients with sulphur mustard exposure are reported for the first time.


Assuntos
Carcinoma/induzido quimicamente , Substâncias para a Guerra Química/intoxicação , Neoplasias de Cabeça e Pescoço/induzido quimicamente , Gás de Mostarda/intoxicação , Dermatopatias/induzido quimicamente , Veteranos , Adulto , Humanos , Exposição por Inalação , Irã (Geográfico) , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Tempo
8.
J Gastrointest Cancer ; 38(1): 15-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-19065717

RESUMO

BACKGROUND: Both esophageal carcinoma and HTLV-1 (Human T cell lymphotropic virus 1) have high prevalence in northeastern of Iran. OBJECTIVE: To assess the presence of HTLV-1 genome in esophageal cancerous tissue and in tissues from non cancerous individuals. METHODS: Eighty five patients with esophageal squamous cell carcinoma and 48 non-cancerous control patients that underwent esophagogasteroscopy for other reasons were included in this study. All selected subjects are residing in northeastern part of Iran. All specimens were studied histopathologically by H&E staining and were evaluated for HTLV-1 by PCR method. In PCR, the presence of tax, pol, env and LTR segments of HTLV-1 genome were detected. RESULTS: Male to female ratio in the case group was 3 to 5. Average age and standard deviation in case and control group were 56 +/- 17 and 54 +/- 21 years, respectively; which did not have any significant differences. All the patients came from the same area in the northeastern part of Iran. HTLV-1 genome was found in two subjects with esophageal cancer and in one subject in the control group. Statistical analysis showed no significant differences between the two groups (chi square = 0.26, Fisher exact test P value = 0.7, Odd ratio = 1.13 [0.08

Assuntos
Carcinoma de Células Escamosas/virologia , Neoplasias Esofágicas/virologia , Infecções por HTLV-I/complicações , DNA Viral/isolamento & purificação , Feminino , Infecções por HTLV-I/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase
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