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1.
Ecotoxicol Environ Saf ; 90: 13-20, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23294636

RESUMO

Experiments were conducted to remove heavy metals (Cr, Cd, Pb, Cu and Zn) from urban sewage sludge (SS) amended with spent mushroom compost (SMC) using worms, Lumbricus rubellus, for 105 days, after 21 days of pre-composting. Five combinations of SS/SMC treatments were prepared in triplicate along with a control for each treatment in microcosms. Analysis of the earthworms' multiplication and growth and laboratory analysis were conducted during the tenth and fifteenth week of vermicomposting. Our result showed that the final biomass of earthworms (mg) and final number of earthworms showed significant differences between treatments i.e. F=554.70, P=0.00 and F=729.10, P=0.00 respectively. The heavy metals Cr, Cd and Pb contained in vermicompost were lower than initial concentrations, with 90-98.7 percent removal on week ten. However, concentrations of Cu and Zn, that are considered as micronutrients, were higher than initial concentrations, but they were 10-200-fold lower than the EU and USA biosolid compost limits and Malaysian Recommended Site Screening Levels for Contaminated Land (SSLs). An increment of heavy metals were recorded in vermicompost for all treatments on week fifteen compared to week ten, while concentration of heavy metals in earthworms' tissue were lower compared to vermicompost. Hence, it is suggested that earthworms begin to discharge heavy metals into their surroundings and it was evident that the earthworms' heavy metals excretion period was within the interval of ten to fifteen weeks.


Assuntos
Metais Pesados/metabolismo , Oligoquetos/fisiologia , Esgotos/química , Poluentes do Solo/metabolismo , Animais , Biomassa , Metais Pesados/análise , Oligoquetos/metabolismo , Solo , Poluentes do Solo/análise , Fatores de Tempo
2.
Cell Death Dis ; 2: e170, 2011 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-21654828

RESUMO

The major cellular event in the development and progression of liver fibrosis is the activation of hepatic stellate cells (HSCs). Activated HSCs proliferate and produce excess collagen, leading to accumulation of scar matrix and fibrotic liver. As such, the induction of activated HSC death has been proposed as a means to achieve resolution of liver fibrosis. Here we demonstrate that cannabidiol (CBD), a major non-psychoactive component of the plant Cannabis sativa, induces apoptosis in activated HSCs through a cannabinoid receptor-independent mechanism. CBD elicits an endoplasmic reticulum (ER) stress response, characterized by changes in ER morphology and the initiation of RNA-dependent protein kinase-like ER kinase-, activating transcription factor-6-, and inositol-requiring ER-to-nucleus signal kinase-1 (IRE1)-mediated signaling cascades. Furthermore, CBD induces downstream activation of the pro-apoptotic IRE1/ASK1/c-Jun N-terminal kinase pathway, leading to HSC death. Importantly, we show that this mechanism of CBD-induced ER stress-mediated apoptosis is specific to activated HSCs, as it occurs in activated human and rat HSC lines, and in primary in vivo-activated mouse HSCs, but not in quiescent HSCs or primary hepatocytes from rat. Finally, we provide evidence that the elevated basal level of ER stress in activated HSCs has a role in their susceptibility to the pro-apoptotic effect of CBD. We propose that CBD, by selectively inducing death of activated HSCs, represents a potential therapeutic agent for the treatment of liver fibrosis.


Assuntos
Apoptose/efeitos dos fármacos , Canabidiol/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Células Estreladas do Fígado/citologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Cultivadas , Relação Dose-Resposta a Droga , Retículo Endoplasmático/metabolismo , Células Estreladas do Fígado/metabolismo , Humanos , Estresse Oxidativo/efeitos dos fármacos , Relação Estrutura-Atividade
3.
BMC Psychiatry ; 9: 71, 2009 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-19917116

RESUMO

BACKGROUND: We have previously reported that the expression of the messenger ribonucleic acid (mRNA) for the NR2A subunit of the N-methyl-D-aspartate (NMDA) class of glutamate receptor was decreased in a subset of inhibitory interneurons in the cerebral cortex in schizophrenia. In this study, we sought to determine whether a deficit in the expression of NR2A mRNA was present in the subset of interneurons that contain the calcium buffer parvalbumin (PV) and whether this deficit was associated with a reduction in glutamatergic inputs in the prefrontal cortex (PFC) in schizophrenia. METHODS: We examined the expression of NR2A mRNA, labeled with a 35S-tagged riboprobe, in neurons that expressed PV mRNA, visualized with a digoxigenin-labeled riboprobe via an immunoperoxidase reaction, in twenty schizophrenia and twenty matched normal control subjects. We also immunohistochemically labeled the glutamatergic axon terminals with an antibody against vGluT1. RESULTS: The density of the PV neurons that expressed NR2A mRNA was significantly decreased by 48-50% in layers 3 and 4 in the subjects with schizophrenia, but the cellular expression of NR2A mRNA in the PV neurons that exhibited a detectable level of this transcript was unchanged. In addition, the density of vGluT1-immunoreactive boutons was significantly decreased by 79% in layer 3, but was unchanged in layer 5 of the PFC in schizophrenia. CONCLUSION: These findings suggest that glutamatergic neurotransmission via NR2A-containing NMDA receptors on PV neurons in the PFC may be deficient in schizophrenia. This may disinhibit the postsynaptic excitatory circuits, contributing to neuronal injury, aberrant information flow and PFC functional deficits in schizophrenia.


Assuntos
Neurônios/metabolismo , Parvalbuminas/metabolismo , Córtex Pré-Frontal/metabolismo , Esquizofrenia/genética , Esquizofrenia/metabolismo , Contagem de Células/estatística & dados numéricos , Digoxigenina/metabolismo , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Interneurônios/metabolismo , Inibição Neural/genética , Inibição Neural/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , Parvalbuminas/genética , Córtex Pré-Frontal/fisiopatologia , RNA Mensageiro/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Esquizofrenia/fisiopatologia , Transmissão Sináptica/genética , Transmissão Sináptica/fisiologia
4.
J Am Mosq Control Assoc ; 11(1): 128-32, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7616179

RESUMO

Several parameters on the oviposition site preference of Aedes albopictus were studied, including color, container type, salinity, and water type. Dark-colored glass jars, especially black, blue, and red ones were preferred over light-colored jars. The black-colored ovitrap with a paper strip performed better than other types of containers. Seasoned tap water had the highest egg count when compared with a saline water series. In addition, water that had previously been used for the culture of Ae. albopictus was the most preferred for oviposition. The significance of this study in conjunction with the present Aedes mosquito surveillance and monitoring program is discussed.


Assuntos
Aedes/fisiologia , Oviposição/fisiologia , Animais , Cor , Feminino , Água
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