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1.
Dermatology ; 229(4): 319-23, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25359191

RESUMO

BACKGROUND: Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) may develop in susceptible patients after administration of different drugs. Only mild cutaneous reactions have been related to lomefloxacin. A correlation between human leucocyte antigen (HLA) and cutaneous adverse reaction has been identified. CASE REPORT: Twenty-four hours after intake of lomefloxacin, a 30-year-old Caucasian woman developed a severe skin reaction with symptoms suggesting SJS/TEN. The fast onset reaction worsened with skin blisters and 20% body surface area skin detachment within 48 h. Burn unit admittance was required; corticosteroids and human immunoglobulins were administered. Complete recovery occurred within 3 months, except for epidermal discoloration. Molecular studies showed a peculiar profile characterized by HLA class I genotype rich of ligands for natural killer cell immunoglobulin-like receptors (KIR) and HLA class II haplotype, HLA-DRB1*03:01,DQB1*02:01, prone to autoimmunity. CONCLUSION: While the HLA profile approaches our case to other well-documented drug-induced SJS/TEN, KIR involvement still remains puzzling.


Assuntos
Antibacterianos/efeitos adversos , Fluoroquinolonas/efeitos adversos , Síndrome de Stevens-Johnson/genética , Adulto , Feminino , Genes MHC Classe I , Genes MHC da Classe II , Genótipo , Antígenos HLA-G/genética , Humanos , Tipagem Molecular , Polimorfismo Genético , Receptores KIR/genética , Síndrome de Stevens-Johnson/etiologia , Síndrome de Stevens-Johnson/terapia
2.
ScientificWorldJournal ; 2014: 259765, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24693232

RESUMO

Silver nanoparticle (AgNP, 20 nm) neurotoxicity was evaluated by an integrated in vitro testing protocol employing human cerebral (SH-SY5Y and D384) cell lines. Cellular response after short-term (4-48 h, 1-100 µ g/ml) and prolonged exposure (up to 10 days, 0.5-50 µ g/ml) to AgNP was assessed by MTT, calcein-AM/PI, clonogenic tests. Pulmonary A549 cells were employed for data comparison along with silver nitrate as metal ionic form. Short-term data: (i) AgNP produced dose- and time-dependent mitochondrial metabolism changes and cell membrane damage (effects starting at 25 µ g/ml after 4 h: EC50s were 40.7 ± 2.0 and 49.5 ± 2.1 µ g/ml for SH-SY5Y and D384, respectively). A549 were less vulnerable; (ii) AgNP doses of ≤ 18 µ g/ml were noncytotoxic; (iii) AgNO3 induced more pronounced effects compared to AgNP on cerebral cells. Long-term data: (i) low AgNP doses (≤ 1 µ g/ml) compromised proliferative capacity of all cell types (cell sensibility: SHSY5Y > A549 > D384). Colony number decrease in SH-SY5Y and D384 was 50% and 25%, respectively, at 1 µ g/ml, and lower dose (0.5 µ g/ml) was significantly effective towards SH-SY5Y and pulmonary cells; (ii) cell proliferation activity was more affected by AgNO3 than AgNPs. In summary, AgNP-induced cytotoxic effects after short-term and prolonged exposure (even at low doses) were evidenced regardless of cell model types.


Assuntos
Apoptose/efeitos dos fármacos , Astrocitoma/fisiopatologia , Sobrevivência Celular/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Neuroblastoma/fisiopatologia , Neurotoxinas/toxicidade , Prata/toxicidade , Astrocitoma/patologia , Bioensaio/métodos , Linhagem Celular Tumoral , Humanos , Neuroblastoma/patologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-38771167

RESUMO

BACKGROUND: The aim of this paper was to evaluate the predictive role of the uterocervical angle (UCA) in spontaneous preterm birth (sPTB). METHODS: A systematic review of the literature was performed including all studies reporting the association between UCA and sPTB. Searches were performed with the use of a combination of keywords: "cervical length," "uterocervical angle," and "preterm birth" from inception of each database to March 2022. The statistical evaluations were carried out using the Comprehensive Meta-Analysis version 3 (Biostat Inc. USA). RESULTS: Sixteen studies all conducted on the second trimester UCA as well as its association with sPTB were included in this study. In all studies the measurements of cervical length (CL) and UCA were performer in the second trimester, except in one that in the third trimester. In most studies the CL is greater than 30 mm and the UCA is greater than 110 °. In seven studies women with symptoms were considered while in 8 studies the women were asymptomatic. CONCLUSIONS: It is too early for it to reach a firm conclusion on UCA utilization in clinical settings. A higher UCA measurement (greater than 150°) is an important risk factor for deliveries before 37 weeks' gestation. It provides a higher diagnostic performance in high risk patients than the CL measurement. However, the most relevant ultrasound parameter for the prediction of delivery within the next few data in women with preterm delivery remains the cervical length. There is a need to consider both markers and create protocols so that the values obtained with UCA and those with CL can make a real contribution to decisions to be made rather than using only CL.

4.
Toxicol Mech Methods ; 23(8): 566-75, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23650964

RESUMO

Abstract Histological and immunocytochemical methods were used to examine rat's renal responses to intratracheal (i.t.) instillation of model cadmium-containing silica nanoparticles (Cd-SiNPs) and also exploring whether these potential modifications would be associated with toxicogenomic changes. Renal effects of Cd-SiNPs (1 mg/rat), CdCl2 (400 µg/rat), SiNPs (600 µg/rat) or 0.1 ml saline (control), assessed 7 and 30 d post-i.t., included (i) induction of apoptosis, (ii) cell proliferation and (iii) the overall toxic response evaluated by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) staining, proliferating cell nuclear antigen (PCNA) immunohistochemistry as well as Periodic acid Schiff and Hematoxylin & Eosin, respectively. Area-specific apoptosis was observed in all treatment groups, the cortex and inner medulla being the most affected regions: the apoptotic changes were apparent seven days post-exposure in both areas and were still observable in inner medulla at day 30. Apoptotic frequency increase was more pronounced in Cd-SiNP-treated animals compared to either CdCl2 or SiNPs groups. At day 7, the observed parallel increased number of PCNA immunopositive cells may be associated with an enhanced cell proliferation aimed at replacing the damaged cells. Histopathological findings demonstrated comparable morphological changes of the renal structure (at glomerular and tubular levels) occurring after all treatments at both time-points and more markedly 30 d after instillation. Both morphological and toxicogenomic evaluations confirmed long-lasting renal effects of Cd-SiNPs on apoptosis and regulatory processes. Bare SiNPs i.t. administration caused morphological and apoptotic changes but did not modify gene expression profile in kidney. These findings substantiate the notion that multiple assays and an integrated testing strategy should be recommended to characterize toxicological responses to nanoparticles in mammalian systems.


Assuntos
Apoptose/efeitos dos fármacos , Rim/efeitos dos fármacos , Nanopartículas/toxicidade , Dióxido de Silício/química , Animais , Marcação In Situ das Extremidades Cortadas , Rim/patologia , Masculino , Ratos , Ratos Sprague-Dawley
5.
J Clin Med ; 12(11)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37297803

RESUMO

INTRODUCTION: A congenital intrathoracic kidney (ITK) is a rare anomaly that is recognized to have four causes: renal ectopia with an intact diaphragm, diaphragmatic eventration, diaphragmatic hernia, and traumatic diaphragmatic rupture. We report a case of a prenatal-diagnosed ITK related to a congenital diaphragmatic hernia (CDH) and conducted a systematic review of all cases of the prenatal diagnosis of this association. CASE PRESENTATION: A fetal ultrasound scan at 22 gestational weeks showed left CDH and ITK, hyperechoic left lung parenchyma, and mediastinal shift. The fetal echocardiography and karyotype were normal. Magnetic resonance imaging at 30 gestational weeks confirmed the ultrasound suspicion of left CDH in association with bowel and left kidney herniation. The fetal growth, amniotic fluid, and Doppler indices remained within the normal range over time. The woman delivered the newborn via an at-term spontaneous vaginal delivery. The newborn was stabilized and underwent non-urgent surgical correction; the postoperative course was uneventful. CONCLUSIONS: CDH is the rarest cause of ITK; we found only eleven cases describing this association. The mean gestational age at diagnosis was 29 ± 4 weeks and 4 days. There were seven cases of right and four cases of left CDH. There were associated anomalies in only three fetuses. All women delivered live babies, the herniated kidneys showed no functional damage after their surgical correction, and the prognosis was favorable after surgical repair. The prenatal diagnosis and counseling of this condition are important in planning adequate prenatal and postnatal management in order to improve neonatal outcomes.

6.
J Clin Med ; 12(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37373772

RESUMO

BACKGROUND AND OBJECTIVES: The present study aims to provide prenatal 2-dimensional ultrasonographic (2D-US) nomograms of the normal cerebellar area. MATERIALS AND METHODS: This is a prospective cross-sectional analysis of 252 normal singleton pregnancies, ranging from 13 to 39 weeks of gestation. The operator performed measurements of the fetal cerebellar area in the transverse plane using 2D-US. The relationship between cerebellar area and gestational age (GA) was determined through regression equations. RESULTS: A significant, strong positive correlation was investigated between the cerebellar area with GA (r-value = 0.89), and a positive correlation indicates that with increasing GA, the cerebellar area increased in all the participants of the study. Several 2D-US nomograms of the normal cerebellar area were provided, and an increase of 0.4% in the cerebellar area each week of GA was reported. CONCLUSIONS: We presented information on the typical dimensions of the fetal cerebellar area throughout gestation. In future studies, it could be evaluated how the cerebellar area changes with cerebellar abnormalities. It should be established if calculating the cerebellar area in addition to the routine transverse cerebellar diameter may help in discriminating posterior fossa anomalies or even help to identify anomalies that would otherwise remain undetected.

7.
Case Rep Womens Health ; 40: e00568, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38094079

RESUMO

Enteric duplication cysts are rare congenital malformations of the gastrointestinal tract. Prenatal diagnosis can be achieved through ultrasound, which may reveal a cystic mass, though the differential diagnosis is broad. We report a case in which the prenatal ultrasound detection of an abdominal cystic mass prompted postnatal magnetic resonance imaging, leading to the diagnosis of an enteric duplication cyst. At 6 weeks of age, the infant developed an obstruction of the small bowel, requiring urgent surgical intervention. This case underscores the difficulties in differentiating abdominal cysts prenatally. Thorough prenatal and neonatal follow-up is crucial, and postnatal magnetic resonance imaging is sometimes essential for accurate diagnosis. The clinical course can be unpredictable, and complications that may arise could necessitate urgent surgical treatment.

8.
G Ital Med Lav Ergon ; 34(2): 175-86, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22888728

RESUMO

There is strong epidemiological evidence that air pollution exposure (short- and long-term, i.e. < 24 hr to 3 weeks, and year/s) is related to exacerbation of cardiovascular and respiratory diseases. Data from toxicological and basic science/molecular studies, controlled animal and human exposures and human panel studies have demonstrated several mechanisms by which particle exposure may both trigger acute events as well as prompt the chronic development of cardiovascular diseases. These pollutant-mediated biological mechanisms are supporting the potential use of haematic (inflammation/coagulation/oxidative stress) markers of effects in cardio-respiratory diseases. Various examples from in vitro, in vivo and epidemiological investigations are reported, together with some novel technologies that should provide with new tools for research in these diseases and improve the knowledge about any linkage of local and systemic inflammation and clinical features of these diseases (in particular COPD), including lung function, exacerbations, disease progression, and mortality.


Assuntos
Poluição do Ar/efeitos adversos , Poluição do Ar/análise , Exposição Ambiental/efeitos adversos , Exposição Ambiental/análise , Monitoramento Ambiental/métodos , Cardiopatias/sangue , Cardiopatias/induzido quimicamente , Inflamação/sangue , Inflamação/induzido quimicamente , Transtornos Respiratórios/sangue , Transtornos Respiratórios/induzido quimicamente , Biomarcadores/sangue , Humanos
9.
Arch Toxicol ; 85(10): 1281-94, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21331603

RESUMO

MeHg (0.5 mg/kg/day) and/or PCB153 (5 mg/kg/day) effects, administered orally to rat dams (GD7-PND21), were explored in PND21 and PND36 offspring brain in terms of density (Bmax) and affinity (Kd) of dopamine D1-like (D1-Rs) and D2-like receptors (D2-Rs), by saturation binding studies. D1-Rs decreased density in both cortex and striatum (15-30%) by MeHg and PCB153, either alone or combined, without additivity in PND21 males. Changes disappeared by PND36. In females, only MeHg caused a 15% Bmax decrease in striatum. D2-Rs enhanced density (23-50%) and reduced affinity in cortex to a similar extent by all treatments in both weanling and pubertal males. Affinity was also decreased in females by all types of exposure at both ages, while density was enhanced by PCB153 only in a delayed manner (PND36). No changes were detected in striatum. In MeHg and MeHg + PCB153 pup cortex, Hg concentrations ranged, on PND21, between 0.25 and 0.89 and 0.94-1.40 µg/g tissue, respectively, and were 5- to sixfold lower 2 weeks later. PCB153 levels, in PCB153 ± MeHg treated rats, were about 15 µg/g tissue (PND21) and 4-8 µg/g tissue (PND36). In striatum, the Hg and PCB153 concentrations were similar to those in cortex. Brain kinetics trend also applied to blood PCB153 or Hg levels. Perinatal exposure to MeHg and/or PCB153 affects D1- and D2-Rs in a gender-, time-, and brain area-dependent manner. Combined treatment does not exacerbate the neurochemical effects of the individual compounds.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/crescimento & desenvolvimento , Compostos de Metilmercúrio/toxicidade , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Animais , Encéfalo/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/crescimento & desenvolvimento , Corpo Estriado/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Feminino , Masculino , Intoxicação do Sistema Nervoso por Mercúrio/metabolismo , Compostos de Metilmercúrio/sangue , Compostos de Metilmercúrio/farmacocinética , Bifenilos Policlorados/sangue , Bifenilos Policlorados/farmacocinética , Gravidez , Puberdade , Ratos , Ratos Sprague-Dawley , Desmame
10.
Biomarkers ; 14(2): 67-76, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19330584

RESUMO

Experimental evidence suggests that monoamine oxidase B (MAO-B) and muscarinic cholinergic receptors (mAChRs) are involved in the pathogenesis of neurotoxicity caused by methylmercury and polychlorinated biphenyls (PCBs). Blood samples from 7-year-old exposed children were analyzed for platelet MAO-B and lymphocyte mAChRs as potential markers of exposure to these neurotoxicants. The blood neurotoxicity biomarkers were compared with prenatal and current exposures and with neuropsychological test results. Both biomarkers showed homogeneous distributions within this cohort (mAChR, range 0.04-36.78 fmol/million cells; MAO-B, 0.95-14.95 nmol mg(-1) protein h(-1)). No correlation was found between the two biomarkers and either blood neurotoxicant concentrations or clinical findings. MAO-B and mAChR sensitivity may not be sufficiently high to assess early, subclinical responses to low/moderate methylmercury and/or PCB exposure, whereas these markers are significantly altered in sustained exposure scenarios, as shown by clinical studies in drug addicts or patients treated with psychopharmacological agents.


Assuntos
Biomarcadores/metabolismo , Plaquetas/efeitos dos fármacos , Linfócitos/metabolismo , Compostos de Metilmercúrio/toxicidade , Monoaminoxidase/metabolismo , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Plaquetas/enzimologia , Criança , Estudos de Coortes , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Gravidez
11.
Biomarkers ; 14(7): 513-22, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19863190

RESUMO

Several lines of evidence support the role of monoaminergic and cholinergic dysregulation in attention deficit hyperactivity disorder (ADHD) and the concept that peripheral blood neurotransmission indices may represent valuable surrogate CNS markers. We determined platelet MAO-B activity (p-MAO-B) and lymphocyte muscarinic cholinergic receptor binding (l-MR) in 44 unmedicated ADHD children (aged 9.1 +/- 2.87 years) and in 26 age-matched controls for comparison. Lower levels of p-MAO-B (approximately 35%) and l-MR (approximately 55%) in ADHD were observed compared with controls. Differences were gender-dependent: p-MAO-B was reduced in males only (5.20 +/- 2.99 vs 8.46 +/- 5.1 nmol mg(-1) protein h(-1) in ADHD and controls, respectively) and l-MR in females only (ADHD vs control: 6.63 +/- 1.75 and 15.30 +/- 8.35 fmol 10(-6) cells). The clinical significance was corroborated by the correlation between these markers and severity of specific symptoms: lower p-MAO-B associated with increased inattention scores (Conners' teacher-rating scale); lower l-MR associated with increased score for oppositional-defiant disorder (ODD) (SNAP-IV); and trend towards correlation between increased inattention (SNAP-IV) and lower l-MR.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/sangue , Plaquetas/enzimologia , Linfócitos/metabolismo , Monoaminoxidase/sangue , Receptor Muscarínico M1/sangue , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Ligação Competitiva , Biomarcadores/sangue , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Escalas de Graduação Psiquiátrica , Receptor Muscarínico M1/metabolismo , Fatores Sexuais
12.
J Chem Neuroanat ; 35(3): 285-94, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18358697

RESUMO

The developing central nervous system (CNS) is a target of the environmental toxicant methylmercury (MeHg), and the cerebellum seems the most susceptible tissue in response to this neurotoxicant. The cholinergic system is essential for brain development, acting as a modulator of neuronal proliferation, migration and differentiation processes; its muscarinic receptors (MRs) play pivotal roles in regulating important basic physiologic functions. By immunohistochemistry, we investigated the effects of perinatal (GD7-PD21) MeHg (0.5 mg/kg bw/day in drinking water) administration on cerebellum of mature (PD36) and immature (PD21) rats, evaluating the: (i) M2- and M3-MR expression; (ii) presence of gliosis; (iii) cytoarchitecture alterations. Regarding to M2-MRs, we showed that: at PD21, MeHg-treated animals did not display any differences compared to controls, while, at PD36 there was a significant increase of M2-immunopositive Bergmann cells in the molecular layer (ML), suggesting a MeHg-related cytotoxic effect. Similarly to M2-MRs, at PD21 the M3-MRs were not affected by MeHg, while, at PD36 a lacking immunoreactivity of the granular layer (IGL) was observed after MeHg treatment. In MeHg-treated rats, at both developmental points, we showed reactive gliosis, e.g. a significant increase in Bergmann glia of the ML and astrocytes of the IGL, identified by their expression of glial fibrillar acidic protein. No MeHg-related effects on Purkinje cells were detected neither at weaning nor at puberty. These findings suggest: (i) a delayed MeHg exposure-related effect on M2- and M3-MRs, (ii) an overt MeHg-related cytotoxic effect on cerebellar oligodendroglia, e.g. reactive gliosis, (iii) a selective vulnerability of granule cells and Purkinje neurons to MeHg, with the latter that remain unharmed.


Assuntos
Cerebelo/metabolismo , Intoxicação do Sistema Nervoso por Mercúrio/metabolismo , Compostos de Metilmercúrio/toxicidade , Receptor Muscarínico M2/metabolismo , Receptor Muscarínico M3/metabolismo , Animais , Calbindina 2 , Calbindinas , Cerebelo/patologia , Corantes , Amarelo de Eosina-(YS) , Feminino , Corantes Fluorescentes , Proteína Glial Fibrilar Ácida/metabolismo , Hematoxilina , Imuno-Histoquímica , Masculino , Intoxicação do Sistema Nervoso por Mercúrio/patologia , Ratos , Ratos Sprague-Dawley , Proteína G de Ligação ao Cálcio S100/metabolismo
13.
Toxicology ; 238(1): 34-48, 2007 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-17618726

RESUMO

In the last few decades, combined exposure to methylmercury (MeHg) and polychlorinated biphenyls (PCBs) from fish and seafood, and their potentially interactive effects on neurodevelopment, have been giving increasing cause for concern. We examined the combined effects of MeHg and either a non-dioxin PCB (PCB153) or a dioxin-like PCB (PCB126) congener on the developing brain cholinergic muscarinic receptors (MRs). These receptors are known to play a major role in many central functions including higher cognitive processes and the modulation of extrapyramidal motor activity. MRs in pup rat brains diminished following prenatal and lactational exposure, from gestational day [GD]7 to postnatal day [PND]21, to MeHg (0.5mg/kgbodyweight[bw]/day), PCB153 (5mg/kgbw/day), and PCB126 (100ng/kg/day), alone or in combination. Total MR density, as well as M1, M2, and M3 receptor subtypes of the weanling and pubertal rats, were affected in a brain-area-, gender-, time- and compound-dependent fashion. MeHg decreased (by 15-20%) the total MR density in a delayed (PND36) manner in the cerebral cortex of both genders, and early (at weaning) in the cerebellum of both genders, with the effect lasting until puberty (in males only). MeHg decreased the ACh M1- and M3-immunopositive neurons in the cerebral cortex and also increased the M2-immunopositive Bergmann glia in the cerebellum. PCB153 also induced a delayed (PND36) decrease (of 20%) in total MR number in the cerebellum of the male offspring and in the cerebral cortex of both genders. The latter effect was coupled with a decrease in ACh M1- and ACh M3-immunopositive neuron populations. PCB126 decreased (by 30-40%) total MR density in a gender-dependent manner, males being more sensitive than females. The effect was evident early (at PND21) and lasted until puberty in the cerebellum, while it was observed later (at PND36) in the cerebral cortex. The M1 and M3 receptors were similarly affected by PCB126. Co-exposure to MeHg and either PCB153 or PCB126 had the same effect on the cerebral MRs as exposure to each compound alone. The results rule out additive or synergistic interactions between MeHg and PCB153 or PCB126 on MRs in the brain areas examined. Some early-onset changes persisted until puberty, while other modifications became manifest only at the advanced time point (PND36), when the brain levels of total Hg, PCB153, and PCB126 had declined. These data support the ability of MeHg and PCBs to induce delayed neurotoxicity after developmental exposure.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Bifenilos Policlorados/toxicidade , Receptores Muscarínicos/metabolismo , Administração Oral , Animais , Cerebelo/efeitos dos fármacos , Cerebelo/metabolismo , Córtex Cerebral/metabolismo , Relação Dose-Resposta a Droga , Feminino , Imuno-Histoquímica , Masculino , Compostos de Metilmercúrio/administração & dosagem , Bifenilos Policlorados/administração & dosagem , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Células de Purkinje/efeitos dos fármacos , Células de Purkinje/metabolismo , Células Piramidais/efeitos dos fármacos , Células Piramidais/metabolismo , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Fatores de Tempo , Trítio , Desmame , Aumento de Peso/efeitos dos fármacos
14.
Neurotox Res ; 11(3-4): 241-60, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17449462

RESUMO

There is an increasing body of evidence on the possible environmental influence on neurodevelopmental and neurodegenerative disorders. Both experimental and epidemiological studies have demonstrated the distinctive susceptibility of the developing brain to environmental factors such as lead, mercury and polychlorinated biphenyls at levels of exposure that have no detectable effects in adults. Methylmercury (MeHg) has long been known to affect neurodevelopment in both humans and experimental animals. Neurobehavioural effects reported include altered motoric function and memory and learning disabilities. In addition, there is evidence from recent experimental neurodevelopmental studies that MeHg can induce depression-like behaviour. Several mechanisms have been suggested from in vivo- and in vitro-studies, such as effects on neurotransmitter systems, induction of oxidative stress and disruption of microtubules and intracellular calcium homeostasis. Recent in vitro data show that very low levels of MeHg can inhibit neuronal differentiation of neural stem cells. This review summarises what is currently known about the neurodevelopmental effects of MeHg and consider the strength of different experimental approaches to study the effects of environmentally relevant exposure in vivo and in vitro.


Assuntos
Poluentes Ambientais/toxicidade , Desenvolvimento Humano/efeitos dos fármacos , Intoxicação do Sistema Nervoso por Mercúrio , Compostos de Metilmercúrio/toxicidade , Animais , Humanos , Intoxicação do Sistema Nervoso por Mercúrio/etiologia , Intoxicação do Sistema Nervoso por Mercúrio/genética , Intoxicação do Sistema Nervoso por Mercúrio/fisiopatologia
15.
Brain Res ; 1112(1): 91-8, 2006 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-16904659

RESUMO

The individual and joint effects of methylmercury (MeHg; 1 mg/kg body weight/day, GD7-PND7) and PCB153 (20 mg/kg body weight/day, GD10-GD16), administered orally to rat dams, were explored in 21-day-old rat offspring brain in terms of monoamine oxidase B (MAO-B) activity and regional content of dopamine (DA), serotonin (5-HT), 5-hydroxy-indole-3-acetic acid (5-HIAA) and homovanillic acid (HVA). Neither treatment altered MAO-B in striatum, hippocampus, cerebellum and cerebral cortex of female pups. In males the cerebellum displayed a significantly reduced enzyme activity (25-45%) following all treatments. Concerning biogenic amines, 5-HT levels were decreased by 30-50% in the cerebral cortex of males and females by PCB153 alone and combined with MeHg, without changes in 5-HIAA and dopaminergic endpoints. In cerebellum of all pups, MeHg enhanced 5-HIAA levels, whereas PCB153, either alone or combined with MeHg, did not affect this endpoint. In striatum, PCB153 reduced the content of DA, HVA and 5-HIAA (respective control values: 2-3; 60-80; 8-10 ng/mg protein) to a similar extent when administered alone or together with MeHg (20-40%). Perinatal exposure to MeHg and/or PCB153 results in regionally and/or gender-specific alterations in the central dopaminergic and serotonergic systems at weaning. The combined treatment with MeHg and PCB153 does not exacerbate the neurochemical effects of the individual compounds.


Assuntos
Química Encefálica/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Compostos de Metilmercúrio/farmacologia , Neurotransmissores/metabolismo , Bifenilos Policlorados/farmacologia , Fatores Etários , Análise de Variância , Animais , Animais Recém-Nascidos , Feminino , Masculino , Gravidez , Ratos , Ratos Sprague-Dawley
16.
Life Sci ; 78(17): 1915-24, 2006 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-16288783

RESUMO

Changes in cerebral cytochrome oxidase (COX) activity, nitric oxide (NO)-cyclic GMP (cGMP) pathway and cholinergic muscarinic receptors (MRs) have been reported in rodents acutely exposed to carbon monoxide (CO). These endpoints measurable in lymphocytes may serve as peripheral markers of CO neurotoxicity. The early and delayed effects of repeated and acute in vivo CO inhalation were investigated on COX activity, cGMP formation and MR binding in rat brain and lymphocytes to assess whether each endpoint was similarly affected both centrally and peripherally. Male Wistar rats either inhaled 500 ppm CO, 6 h/day, 5 days/week, 4 weeks (repeated exposure) or 2,400 ppm, 1 h (single exposure). Neither treatment altered brain or lymphocyte COX activity 1 and 7 days post-treatment. Also ineffective were repeated and acute CO treatments towards (3)H-quinuclidinyl benzilate (QNB) binding to MRs in cerebral cortex, hippocampus, striatum, cerebellum (respective controls, mean+/-S.D.: 171 +/- 45, 245 +/- 53, 263 +/- 14 and 77 +/- 7 fmol/mg protein) and lymphocytes (24 +/- 10 fmol/million cells) at the same time points. In lymphocytes control cGMP levels averaged 1.98 +/- 0.99 pmol/mg protein under basal conditions, and 3.94 +/- 0.55 pmol/mg protein after NO-stimulation. One day after chronic treatment cessation, the CO-treated group displayed about a 50% decrease in both basal and NO-stimulated cGMP values, which persisted up to 7 days after, compared to air-exposed rats. Acutely, CO caused a delayed enhancement (+140%) of NO-induced activation of soluble guanylate cyclase. The finding that the NO-cGMP pathway is a target for the delayed effects of CO in peripheral blood cells is in accordance with our data in brain [Hernández-Viadel, M., Castoldi, A.F., Coccini, T., Manzo, L., Erceg, S., Felipo, V., 2004. In vivo exposure to carbon monoxide causes delayed impairment of activation of soluble guanylate cyclase by nitric oxide in rat brain cortex and cerebellum. Journal of Neurochemistry 89, 1,157-1,165], and supports the use of this peripheral endpoint as a biomarker of CO central effects.


Assuntos
Encéfalo/efeitos dos fármacos , Intoxicação por Monóxido de Carbono/sangue , Monóxido de Carbono/toxicidade , GMP Cíclico/metabolismo , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Linfócitos/enzimologia , Receptores Muscarínicos/metabolismo , Animais , Biomarcadores/sangue , Encéfalo/metabolismo , Relação Dose-Resposta a Droga , Guanilato Ciclase/sangue , Exposição por Inalação , Masculino , Neurônios/efeitos dos fármacos , Neurônios/patologia , Ratos , Ratos Wistar
17.
Neurotoxicology ; 27(4): 468-77, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16455139

RESUMO

The developing nervous system is thought to be particularly sensitive to polychlorinated biphenyls (PCBs) present as food contaminants together with methylmercury (MeHg). Effects of perinatal co-exposure to PCB153 and MeHg on brain cholinergic muscarinic receptors (MRs) were investigated by saturation binding studies in mature and immature rats. MeHg alone (1mg/kg/day, GD7-PND7) enhanced cerebral MRs more in dams (87% and 60% in cerebellum and cerebral cortex, respectively) than in PND21 pups (0-50%) in accordance with the higher Hg levels detected in the adult brain (7-9 microg/g) than in the male and female offspring's brain (1.5-2.8 microg/g). Prenatal administration of PCB153 (20mg/kg/day, GD10-GD16), leading to higher contaminant levels in the offspring brain than in that of adults (25-66 microg/g versus 3 microg/g), induced cerebral MR changes of similar extent at both ages, namely decreased cerebellar (20-30%) and increased cortical MR density (40-50%). Co-exposure to PCB and MeHg had no more effect than exposure to either compound alone on cerebral cortex MRs, whereas, in the cerebellum, the combined treatment induced a PCB-like lowering of the MR density that masked the MeHg-induced receptor increase. None of the treatments affected the striatal and hippocampal MRs. A lower MeHg dose (0.5 mg/kg/day) was without any effect on cerebral MRs. These results show that MRs are one of the sensitive biochemical endpoints of the central nervous system altered by developmental exposure to MeHg and PCB153. Cerebral cortex and cerebellum were the most susceptible targets in the response to these neurotoxicants. MR changes were detected in both immature and adult animals and the interaction of MeHg and PCB153 at the level of these receptors occurred in a non-additive manner.


Assuntos
Encéfalo/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Bifenilos Policlorados/toxicidade , Efeitos Tardios da Exposição Pré-Natal , Receptores Muscarínicos/metabolismo , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/crescimento & desenvolvimento , Encéfalo/patologia , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Masculino , Compostos de Metilmercúrio/metabolismo , Antagonistas Muscarínicos/farmacocinética , Bifenilos Policlorados/metabolismo , Gravidez , Ligação Proteica/efeitos dos fármacos , Quinuclidinil Benzilato/farmacocinética , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Fatores Sexuais , Trítio/farmacocinética
18.
Ann Ist Super Sanita ; 42(3): 298-309, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-17124354

RESUMO

The availability of antidotes in Italian hospitals has been evaluated through the answers to a specific questionnaire sent to all Italian Emergency Departments, Intensive Care Units, 118 emergency response system, and Poison Centres. Five Poison Centres and, approximately, the 30% of the Emergency Departments and Intensive Care Units of all Italian emergency hospitals answered to the questionnaire. The results point out an insufficient availability of antidotes in the Italian emergency hospitals, with an almost total absence of those necessary for the treatment of less frequent and less known poisonings (e.g. digoxin, industrial agents), also when the antidote is a lifesaving drug. To improve the antidotes availability for the toxicological emergencies and to facilitate its supplying, a "national antidotes data-base" (BaNdA) has been realized, freely available to the hospital services which register themselves and make their antidotes stockpile available.


Assuntos
Antídotos/provisão & distribuição , Bases de Dados Factuais , Serviço Hospitalar de Emergência/estatística & dados numéricos , Coleta de Dados , Humanos , Itália , Centros de Controle de Intoxicações , Inquéritos e Questionários
19.
Environ Toxicol Pharmacol ; 19(3): 715-20, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-21783547

RESUMO

Lymphocyte cholinergic muscarinic receptors (MRs) and platelet monoamine oxidase-B (MAO-B) activity are considered surrogate markers of the same parameters in the central nervous system. Lymphocyte MR binding and platelet MAO-B activity were measured in a consistent number of healthy human adults and analysed according to gender and age. The mean value±S.D. of MR binding neither differed between males (12.2±10.0fmol/10(6)cells, range: 0.5-37.9, n=86) and females (10.7±9.7fmol/10(6)cells, range: 0.5-39.7, n=69) nor among age groups. MAO-B activity was significantly higher in women (geometric mean: 11.3nmol/mgprotein/h, with 65% of values from 7.3 to 17.6; n=43), than in men (7.7nmol/mgprotein/h, with 65% of values from 4.5 to 13; n=95). Males aged 56-66 years displayed a higher, though not statistically significant, basal enzyme activity than younger subjects. Altogether these data indicate gender-related differences in MAO activity, but not in MR binding, and inter-individual differences in the basal values of both peripheral blood markers in healthy subjects.

20.
Amyloid ; 22(4): 221-8, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26466638

RESUMO

The increasing number of applications of silver nanoparticles (AgNP) prompted us to assess their toxicity in vivo. We have investigated their effects on wild type and transgenic Caenorhabditis elegans (C. elegans) strains expressing two prototypic amyloidogenic proteins: ß2-microglobulin and Aß peptide3-42. The use of C. elegans allowed us to highlight AgNP toxicity in the early phase of the worm's life cycle (LC50 survival, 0.9 µg/ml). A comparative analysis of LC50 values revealed that our nematode strains were more sensitive to assess AgNP toxicity than the cell lines, classically used in toxicity tests. Movement and superoxide production in the adult population were significantly affected by exposure to AgNP; the transgenic strains were more affected than the wild type worms. Our screening approach could be applied to other types of nanomaterials that can enter the body and express any nanostructure-related bioactivities. We propose that C. elegans reproducing the molecular events associated with protein misfolding diseases, e.g. Alzheimer's disease and systemic amyloidosis, may help to investigate the specific toxicity of a range of potentially harmful molecules. Our study suggests that transgenic C. elegans may be used to predict the effect of chemicals in a "fragile population", where an underlying pathologic state may amplify their toxicity.


Assuntos
Proteínas Amiloidogênicas/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Nanopartículas Metálicas/toxicidade , Prata/química , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/metabolismo , Linhagem Celular Tumoral , Humanos , Nanopartículas Metálicas/química , Espécies Reativas de Oxigênio/metabolismo
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