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1.
Environ Technol ; 35(9-12): 1462-9, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24701944

RESUMO

Activated sludge process is the most widely diffused system to treat wastewater to control the discharge of pollutants into the environment. Microorganisms are responsible for the removal of organic matter, nitrogen, phosphorous and other emerging contaminants. The environmental conditions of biological reactors significantly affects the ecology of the microbial community and, therefore, the performance of the treatment process. In the last years, ozone has been used to reduce excess sludge production by wastewater treatment plants (WWTPs), whose disposal represents one of the most relevant operational costs. The ozonation process has demonstrated to be a viable method to allow a consistent reduction in excess sludge. This study was carried out in a full-scale plant treating municipal wastewater in two parallel lines, one ozonated in the digestion tank and another used as a control. Bacterial communities of samples collected from both lines of digestion thanks were then compared to assess differences related to the ozonation treatment. Data were then analysed with terminal restriction fragment length polymorphism (T-RFLP) analysis on 16S rRNA gene. Differences between bacterial communities of both treated and untreated line appeared 2 weeks after the beginning of the treatment. Results demonstrated that ozonation treatment significantly affected the activated sludge in WWTP.


Assuntos
Consórcios Microbianos , Ozônio , Esgotos , Gerenciamento de Resíduos , Polimorfismo de Fragmento de Restrição
2.
Nat Genet ; 15(4): 393-6, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9090386

RESUMO

Progressive myoclonus epilepsy of Unverricht-Lundborg type (EPM1; MIM 254800) is an autosomal recessive disorder that occurs with a low frequency in many populations but is more common in Finland and the Mediterranean region. It is characterized by stimulus-sensitive myoclonus and tonic-clonic seizures with onset at age 6-15 years, typical electroencephalographic abnormalities and a variable rate of progression between and within families. Following the initial mapping of the EPM1 gene to chromosome 21 (ref. 6) and the refinement of the critical region to a small interval, positional cloning identified the gene encoding cystatin B (CST6), a cysteine protease inhibitor, as the gene underlying EPM1 (ref. 10). Levels of messenger RNA encoded by CST6 were dramatically decreased in patients. A 3' splice site and a stop codon mutation were identified in three families, leaving most mutations uncharacterized. In this study, we report a novel type of disease-causing mutation, an unstable 15- to 18-mer minisatellite repeat expansion in the putative promoter region of the CST6 gene. The mutation accounts for the majority of EPM1 patients worldwide. Haplotype data are compatible with a single ancestral founder mutation. The length of the repeat array differs between chromosomes and families, but changes in repeat number seem to be comparatively rare events.


Assuntos
Cistatinas/genética , Epilepsias Mioclônicas/genética , Repetições Minissatélites/genética , Mutação/genética , Cistatina B , Feminino , Efeito Fundador , Humanos , Masculino , Dados de Sequência Molecular , Polimorfismo Genético , Regiões Promotoras Genéticas/genética , Mapeamento por Restrição
3.
Diabet Med ; 27(10): 1195-200, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20854389

RESUMO

AIMS: Permanent neonatal diabetes is a rare condition affecting 1 in 300,000-400,000 live births; only in 60% of cases it is possible to identify the genetic defect. The condition of pancreatic agenesis is rarer still. Only two genes are known to determine this phenotype: PDX-1 and PTF1A. Congenital heart defects are among the most common developmental anomalies, affecting 1% of newborns, and the GATA4 gene is less frequently involved in these disorders. An Italian child with pancreatic agenesis and an atrial septal defect was genetically investigated to elucidate whether the association of the two pathologies was casual, or represented a new pancreatic/cardiac syndrome. METHODS: A panel of pancreas development genes, including GCK, Kir6.2, PTF1A, PDX-1, HNF-1A, NgN3, SOX17, SOX7, SOX9, INS, HNF1-B and SUR1 plus the GATA4 gene, were screened for characterization of pancreatic agenesis and cardiac defect. RESULTS: Screening for genes causing permanent neonatal diabetes was negative. A novel mutation in GATA4 (c1512C>T) was detected and functional characterization confirmed a reduced activity of the protein. In the family members, the GATA4 mutation co-segregates with a cardiac phenotype, but not with pancreatic agenesis. CONCLUSIONS: We describe the first report of pancretic agenesis with an associated cardiac defect and a mutation in the GATA4 gene. We could not establish that the GATA4 mutation was causative for pancreatic agenesis and further genetic investigation to detect the genetic cause of the pancreas agenesis was unsuccessful. We conclude that, the two pathologies are attributable to two independent events.


Assuntos
Diabetes Mellitus Tipo 1/genética , Fator de Transcrição GATA4/genética , Comunicação Interatrial/genética , Pré-Escolar , Anormalidades Congênitas/genética , Análise Mutacional de DNA , Diabetes Mellitus Tipo 1/diagnóstico , Comunicação Interatrial/diagnóstico , Humanos , Imageamento por Ressonância Magnética , Masculino , Mutação , Pâncreas/anormalidades
4.
Plant Methods ; 16: 61, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377221

RESUMO

BACKGROUND: Reproductive success in seed plants depends on a healthy fruit and seed set. Normal seed development in the angiosperms requires the production of functional female gametophytes. This is particularly evident in seedless cultivars where defects during megagametophyte's developmental processes have been observed through cytohistological analysis. Several protocols for embryo sac histological analyses in grapevine are reported in literature, mainly based on resin- or paraffin-embedding approaches. However their description is not always fully exhaustive and sometimes they consist of long and laborious steps. The use of different stains is also documented, some of them, such as hematoxylin, requiring long oxidation periods of the dye-solution before using it (from 2 to 6 months) and/or with a differentiation step not easy to handle. Paraffin-embedding associated to examination with light microscope is the simplest methodology, and with less requirements in terms of expertise and costs, achieving a satisfactory resolution for basic histological observations. Safranin O and fast green FCF is an easy staining combination that has been applied in embryological studies of several plant species. RESULTS: Here we describe in detail a paraffin-embedding method for the examination of grapevine ovules at different phenological stages. The histological sample preparation process takes 1 day and a half. Sections of 5 µm thickness can be obtained and good contrast is achieved with the safranin O and fast green FCF staining combination. The method allows the observation of megasporogenesis and megagametogenesis events in the different phenological stages examined. CONCLUSIONS: The histological sample preparation process proposed here can be used as a routine procedure to obtain embedded ovaries or microscope slides that would require further steps for examination. We suggest the tested staining combination as a simple and viable technique for basic screenings about the presence in grapevine of a normally and fully developed ovule with embryo sac cells, which is therefore potentially functional.

5.
Science ; 271(5256): 1731-4, 1996 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-8596935

RESUMO

Progressive myoclonus epilepsy of the Unverricht-Lundborg type (EPM1) is an autosomal recessive inherited form of epilepsy, previously linked to human chromosome 21q22.3. The gene encoding cystatin B was shown to be localized to this region, and levels of messenger RNA encoded by this gene were found to be decreased in cells from affected individuals. Two mutations, a 3' splice site mutation and a stop codon mutation, were identified in the gene encoding cystatin B in EPM1 patients but were not present in unaffected individuals. These results provide evidence that mutations in the gene encoding cystatin B are responsible for the primary defect in patients with EPM1.


Assuntos
Cromossomos Humanos Par 21/genética , Cistatinas/genética , Inibidores de Cisteína Proteinase/genética , Epilepsias Mioclônicas/genética , Sequência de Aminoácidos , Sequência de Bases , Mapeamento Cromossômico , Códon de Terminação/genética , Cistatina B , Cistatinas/química , Inibidores de Cisteína Proteinase/química , Feminino , Finlândia , Expressão Gênica , Genes Recessivos , Humanos , Íntrons/genética , Desequilíbrio de Ligação , Masculino , Dados de Sequência Molecular , Linhagem , Mutação Puntual , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Recombinação Genética
6.
Diabet Med ; 25(6): 651-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18544102

RESUMO

AIMS: Heterozygous activating mutations in KCNJ11, which encodes the Kir6.2 subunit of the pancreatic ATP-sensitive potassium (K(ATP)) channel, cause both permanent and transient neonatal diabetes. Identification of KCNJ11 mutations has important therapeutic implications, as many patients can replace insulin injections with sulphonylurea tablets. The aim was to determine if a KCNJ11 mutation was responsible for a dominantly inherited form of diabetes mellitus, showing variability in age at diagnosis, in an Italian family. METHODS: We sequenced KCNJ11 in members of a three-generation family with variable phenotypes of dominantly inherited diabetes mellitus. One had transient early-onset diabetes, one had impaired glucose tolerance during the second pregnancy, and two had young-onset diabetes. None of the subjects showed permanent neonatal diabetes or neurological symptoms. RESULTS: A novel heterozygous mutation (c. 679C-->G and c. 680A-->T) was identified, resulting in a GAG-->CTG (E227L) substitution in KCNJ11. Functional studies of recombinant heterozygous K(ATP) channels revealed a small reduction in channel inhibition by ATP (IC(50) of 15 micromol/l and 38 micromol/l for wild-type and heterozygous channels, respectively) and an increase in the resting K(ATP) current. This would be expected to impair insulin secretion. The results are in agreement with the mild phenotype of the patients. CONCLUSIONS: Our results broaden the spectrum of diabetes phenotypes resulting from KCNJ11 mutations. They indicate testing for KCNJ11 mutations should be considered not only for neonatal diabetes but also for other forms of dominantly inherited diabetes with later onset, especially where these are associated with a low body mass index and low birth weight.


Assuntos
Diabetes Mellitus/genética , Mutação/genética , Canais de Potássio Corretores do Fluxo de Internalização/genética , Adulto , Feminino , Heterozigoto , Humanos , Masculino , Linhagem , Fenótipo , Gravidez
7.
Cancer Res ; 54(5): 1190-3, 1994 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-8118804

RESUMO

Significant inhibition of proliferative activity in PC3 human prostate cancer cells by estradiol is reported, accompanied by experimental evidence for a specific estrogen receptor (ER). Radioligand-binding assays revealed the presence of high affinity sites of estrogen binding in the nuclear compartment of PC3 cells. In addition, using a reverse transcriptase-polymerase chain reaction system, we obtained evidence of either normal or a variant ER mRNA; the latter, which lacks the entire exon 4, is coexpressed with normal ER mRNA and has been recently characterized in our laboratories. The likelihood that the inhibitory effect exerted by estradiol could be mediated by an increase of transforming growth factor beta (TGF beta) production was also investigated. Use of monoclonal antibodies against TGF beta 1 produced a 3-fold increase of growth rate in PC3 cells; this clearly speaks for high levels of endogenous TGF beta 1. This effect was almost completely abolished after addition of 100 nM estradiol. However, we failed to demonstrate any increase of TGF beta 1 mRNA after estradiol administration using Northern blot analysis. Further studies are needed to ascertain whether the estradiol-induced growth inhibition of PC3 cells is either mediated by other TGF beta species or exerted via alternative mechanism(s).


Assuntos
Estradiol/farmacologia , Neoplasias Hormônio-Dependentes/tratamento farmacológico , Neoplasias da Próstata/tratamento farmacológico , Northern Blotting , Southern Blotting , Divisão Celular/efeitos dos fármacos , Humanos , Cinética , Masculino , Neoplasias Hormônio-Dependentes/patologia , Neoplasias Hormônio-Dependentes/ultraestrutura , Reação em Cadeia da Polimerase , Neoplasias da Próstata/patologia , Neoplasias da Próstata/ultraestrutura , RNA Mensageiro/análise , Receptores de Estrogênio/genética , Receptores de Estrogênio/fisiologia , Fator de Crescimento Transformador beta/genética , Fator de Crescimento Transformador beta/fisiologia , Células Tumorais Cultivadas/efeitos dos fármacos
8.
Waste Manag ; 48: 209-217, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26586420

RESUMO

This paper evaluates the effect of ultrasonication on anaerobic biodegradability of lignocellulosic residues. While ultrasonication has been commonly applied as a pre-treatment of the feed substrate, in the present study a non-conventional process configuration based on recirculation of sonicated digestate to the biological reactor was evaluated at the lab-scale. Sonication tests were carried out at different applied energies ranging between 500 and 50,000kJ/kg TS. Batch anaerobic digestion tests were performed on samples prepared by mixing sonicated and untreated substrate at two different ratios (25:75 and 75:25 w/w). The results showed that when applied as a post-treatment of digestate, ultrasonication can positively affect the yield of anaerobic digestion, mainly due to the dissolution effect of complex organic molecules that have not been hydrolyzed by biological degradation. A good correlation was found between the CH4 production yield and the amount of soluble organic matter at the start of digestion tests. The maximum gain in biogas production was 30% compared to that attained with the unsonicated substrate, which was tentatively related to the type and concentration of the metabolic products.


Assuntos
Biocombustíveis , Eliminação de Resíduos/métodos , Resíduos Sólidos , Ultrassom/métodos , Anaerobiose , Biodegradação Ambiental , Alimentos , Hidrólise , Lignina/química , Metano/biossíntese , Esgotos/química
9.
Br J Pharmacol ; 120(1): 19-24, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9117093

RESUMO

1. Cardiac effects on norbormide and verapamil were compared in single ventricular myocytes, right atria, and Langendorff perfused hearts isolated from guinea-pigs. 2. In ventricular myocytes, norbormide 50 microM inhibited the peak calcium current (ICa) by 49.6 +/- 3.9% without altering the shape of the current-voltage relationship; verapamil 1 microM inhibited ICa by 83.2 +/- 3.3%. Neither norbormide nor verapamil affected ICa at the first beat after a 3 min quiescence period; during repeated depolarizations, both drugs cumulatively blocked ICa (use-dependence), with time constants of 23.0 +/- 7.0 s for norbormide and 91.3 +/- 8.4 s for verapamil. 3. In constant-flow perfused hearts electrically driven at 2.5 Hz or 3.3 Hz, both norbormide and verapamil concentration-dependently decreased ventricular contractility (dP/dtmax), atrio-ventricular (AV) conduction velocity and coronary pressure. Intraventricular conduction velocity was slightly decreased by norbormide but not by verapamil. At an equivalent change in AV conduction, norbormide depressed heart contractility less than verapamil. The effects of norbormide on AV conduction, intraventricular conduction, and contractility were frequency-dependent. Furthermore, the curves correlating the mechanical and electrical effects of norbormide at the two frequencies used were apparently coincident, while those of verapamil were clearly separated. 4. In spontaneously beating right atria, norbormide and verapamil decreased the frequency of sinus node (SA) in a concentration-dependent way. At an equivalent effect on the AV conduction, norbormide exerted a greater effect on sinus frequency than verapamil. 5. These results indicate that in guinea-pig heart norbormide has the pharmacological profile of a Ca-antagonist with strong electrophysiological properties. In comparison with verapamil, norbormide is more selective on SA and AV node tissues and exerts a weaker negative inotropic effect on ventricles. In principle, this pattern of effects may be an advantage in treating supraventricular tachyarrhythmias in patients with heart failure. The effect of norbormide on intraventricular conduction may represent an additional antiarrhythmic mechanism.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Coração/efeitos dos fármacos , Norbornanos/farmacologia , Verapamil/farmacologia , Animais , Canais de Cálcio/efeitos dos fármacos , Canais de Cálcio/metabolismo , Eletrofisiologia , Feminino , Cobaias , Sistema de Condução Cardíaco/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Hemodinâmica/efeitos dos fármacos , Técnicas In Vitro , Masculino , Potenciais da Membrana/efeitos dos fármacos , Contração Miocárdica/efeitos dos fármacos , Miocárdio/citologia , Técnicas de Patch-Clamp
10.
Leuk Lymphoma ; 15(1-2): 135-41, 1994 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-7858491

RESUMO

Peripheral blood mononuclear cells from seventeen patients with primary myelodysplastic syndromes (MDS) in advanced stage were enriched for blasts and tested for (1) karyotype, (2) genomic configuration and (3) expression of IL-3, GM-CSF, FMS and EGR-1 genes which are all located on the long arm of chromosome 5. The expression of the M-CSF gene, that has been recently reassigned to the short arm of chromosome 1 (lp), was also investigated. Aims of the study were to (1) assess the potential role of the expression of these genes in the maintenance and expansion of the neoplastic clones and (2) search for constitutional losses or rearrangements of one allele followed by a deletion of the second allele of the same genes in the leukemic cells. The latter issue was investigated by comparing, in 8 cases, constitutive DNA from skin fibroblasts with leukemic DNA. Eleven of the 17 patients had abnormal karyotypes. The M-CSF gene was expressed in 6 cases and the FMS and the EGR-1 genes were expressed in 2 of the latter cases. An autocrine mechanism of growth could be hypothesized only for the 2 patients whose cells expressed both the M-CSF and FMS genes. No germline changes or rearrangements were observed in any of the genes studied. Thus, deregulation of genes encoding for certain hemopoietic growth factors or receptors does not seem to represent a major mechanism of MDS progression.


Assuntos
Cromossomos Humanos Par 5 , Proteínas de Ligação a DNA/genética , Fator Estimulador de Colônias de Granulócitos e Macrófagos/genética , Proteínas Imediatamente Precoces , Interleucina-3/genética , Fator Estimulador de Colônias de Macrófagos/genética , Síndromes Mielodisplásicas/genética , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Fatores de Transcrição/genética , Idoso , Idoso de 80 Anos ou mais , Alelos , Aberrações Cromossômicas , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 5/ultraestrutura , Proteínas de Ligação a DNA/biossíntese , Proteína 1 de Resposta de Crescimento Precoce , Feminino , Fibroblastos/patologia , Regulação da Expressão Gênica , Genes , Fator Estimulador de Colônias de Granulócitos e Macrófagos/biossíntese , Humanos , Interleucina-3/biossíntese , Cariotipagem , Fator Estimulador de Colônias de Macrófagos/biossíntese , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Monócitos/patologia , Síndromes Mielodisplásicas/patologia , Hibridização de Ácido Nucleico , Receptor de Fator Estimulador de Colônias de Macrófagos/biossíntese , Deleção de Sequência , Fatores de Transcrição/biossíntese
11.
Pediatr Med Chir ; 17(6): 531-3, 1995.
Artigo em Italiano | MEDLINE | ID: mdl-8668589

RESUMO

The Authors report the cases of Kawasaki disease (K.D.) observed between July 1988 and october 1991 in OO.RR.'s Pediatric Division of Foggia. The diagnosis was made according to the C.D.C.'s Atlanta diagnostic guidelines. All children were treated (whithin the first 10 days of onset of illness) with intravenous immune-globuline (500 mg/kg/die for 5 days) and with Asa and Dypiridamol for two months after they were without temperature. The patients with coronaric sequelae repeated after 4 weeks a second cycle of intravenous immuno-globuline therapy and continued Asa and Dypiridamol therapy until two months after disappearance of coronary arterial abnormalities. All patients performed ECG at 3-15-30 days and at 180-360 days from the onset of illness. A mono-bidimensional ecocardiogram was performed twice a week in the first month, bi-monthly in the next months and after 180-360 days from the onset of illness. One of the 8 children developed coronary aneurysms, which regressed echocardiographycally during the first 6 months after the acute illness. While the etiology and pathogenesis of K.D. remain incompletely understood, the clinical spectrum of the disorder and its long-term prognosis and treatment are becoming increasingly well defined. Coronary artery aneurysms developed in 15-25% of cases, with a mortality for coronary artery thrombosis of 1-2% of cases. Intravenous immuno-globuline infusion given in the early phases of the disorder reduce the incidence of coronary artery aneurysms therefore an early diagnosis is important to prevent coronary artery abnormalities.


Assuntos
Cardiopatias/etiologia , Síndrome de Linfonodos Mucocutâneos/complicações , Fatores Etários , Anti-Inflamatórios não Esteroides/uso terapêutico , Aspirina/uso terapêutico , Pré-Escolar , Aneurisma Coronário/diagnóstico , Aneurisma Coronário/etiologia , Dipiridamol/uso terapêutico , Ecocardiografia , Eletrocardiografia , Feminino , Cardiopatias/diagnóstico , Cardiopatias/tratamento farmacológico , Humanos , Imunoglobulinas Intravenosas/uso terapêutico , Lactente , Masculino , Síndrome de Linfonodos Mucocutâneos/diagnóstico , Síndrome de Linfonodos Mucocutâneos/tratamento farmacológico , Inibidores da Agregação Plaquetária/uso terapêutico , Prognóstico , Fatores de Tempo , Vasodilatadores/uso terapêutico
12.
Pediatr Med Chir ; 15(4): 405-7, 1993.
Artigo em Italiano | MEDLINE | ID: mdl-8265464

RESUMO

Candida albicans is the most prevalent and pathogenic fungal infection of the urinary tract. Although fungal urinary tract infection occur less frequently than bacterial infections, their incidence has increased during the last decades. Parenteral nutrition, corticosteroids, immunosuppressive drugs and prolonged antibiotic therapy are often predisposing factors. We report a case of renal pelvic fungus balls in a 6-month old female who developed candidal infection after surgical treatment for bilateral vesico-ureteric reflux; the renal candidiasis was treated successfully with fluconazole.


Assuntos
Candidíase/diagnóstico , Nefropatias/diagnóstico , Micetoma/diagnóstico , Complicações Pós-Operatórias/diagnóstico , Candidíase/tratamento farmacológico , Candidíase/etiologia , Feminino , Fluconazol/uso terapêutico , Humanos , Lactente , Nefropatias/tratamento farmacológico , Nefropatias/etiologia , Micetoma/tratamento farmacológico , Micetoma/etiologia , Complicações Pós-Operatórias/tratamento farmacológico , Complicações Pós-Operatórias/etiologia , Bexiga Urinária/cirurgia , Derivação Urinária , Refluxo Vesicoureteral/complicações , Refluxo Vesicoureteral/diagnóstico , Refluxo Vesicoureteral/cirurgia
13.
Circulation ; 91(10): 2510-5, 1995 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-7743611

RESUMO

BACKGROUND: The relation between early afterdepolarizations (EADs) and changes in intracellular Ca2+ concentration ([Ca2+]i) is still unclear. In the present study, we compared spatiotemporal changes in [Ca2+]i related to EADs and delayed afterdepolarizations (DADs) induced by isoproterenol. METHODS AND RESULTS: Isolated patch-clamped guinea pig ventricular myocytes, loaded with fluo-3 acetoxymethyl ester (fluo-3 AM), were paced at 0.1 to 2 Hz. Isoproterenol (100 nmol/L) caused alterations in both phase 2 and phase 4 of the action potential (AP), consistent with EADs and DADs, respectively. During EADs (n = 16), similar to driven APs, increases in [Ca2+]i occurred simultaneously throughout the cell, whereas during DADs (n = 25), they originated in discrete cell sites and propagated as a wave. This difference was confirmed by analysis of eight EADs and DADs coupled to the same beat. Ca2+ transient linked to EADs reached a peak relative fluorescence level (expressed as percentage of the maximal level reached during the last stimulated beat) that was always higher than that reached during the DADs (77 +/- 3% versus 64 +/- 2%, P < .001). Spatial heterogeneity of Ca2+ transients was assessed by the maximal time interval between peaks monitored in different cell regions; this time lag was always greater during DADs than during EADs (290 versus 40 milliseconds, P = .006). CONCLUSIONS: The present study had two main findings. First, even very modest notches occurring during the plateau of the AP may be accompanied by a marked secondary increase in [Ca2+]i. Second, these Ca2+ transients occurring during EADs are synchronous throughout the cell and differ significantly from those observed under identical conditions during DADs.


Assuntos
Cálcio/fisiologia , Isoproterenol/farmacologia , Função Ventricular/efeitos dos fármacos , Compostos de Anilina , Animais , Eletrofisiologia , Corantes Fluorescentes , Cobaias , Masculino , Miocárdio/citologia , Fatores de Tempo , Xantenos
14.
Inhal Toxicol ; 13(11): 1033-45, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11696872

RESUMO

The subchronic inhalation toxicity of ammonium persulfate was characterized using Sprague-Dawley rats (20/sex/group) at respirable dust concentrations of 0, 5.0, 10.3, and 25 mg/m(3). Whole-body exposures were conducted 6 h/day, 5 days/wk for 13 wk. Gravimetric airborne test material samples were taken daily and particle size samples were taken weekly from each exposure chamber for analysis. Ten animals/sex/group were necropsied after 13 wk of exposure, and 5 animals/sex/group were held for 6- and 13-wk recovery periods. Animals were observed for clinical signs. Effects on body weight, food consumption, clinical chemistry and hematology, ophthalmologic parameters, organ weights, gross lesions, and histopathology were evaluated. There were no exposure-related deaths during the study. Rales and increased respiration rate were noted in both males and females in the 25 mg/m(3) group, and in a few animals in the 10.3 mg/m(3) group. The incidence of these clinical signs decreased to zero during the first few weeks of the recovery period. Body weights for both males and females in the 25 mg/m(3) group were significantly depressed during most of the exposure period compared to the control group. By the end of the recovery period, body weights for the exposed animals were similar to the control group values. Lung weights were elevated in the 25 mg/m(3) group after 13 wk of exposure, but were similar to controls at 6 wk postexposure. Irritation of the trachea and bronchi/bronchiole was noted microscopically after 13 wk of exposure to 25 mg/m(3). These lesions had recovered by 6 wk postexposure. Based on the results of this study, the no-observed-adverse-effect level (NOAEL) was 10.3 mg/m(3), while the no-observed-effect level (NOEL) for exposure of rats to a dust aerosol of ammonium persulfate was 5.0 mg/m(3).


Assuntos
Sulfato de Amônio/toxicidade , Sistema Respiratório/patologia , Sulfato de Amônio/administração & dosagem , Animais , Peso Corporal , Relação Dose-Resposta a Droga , Poeira , Ingestão de Alimentos , Feminino , Exposição por Inalação , Masculino , Nível de Efeito Adverso não Observado , Ratos , Ratos Sprague-Dawley , Sistema Respiratório/efeitos dos fármacos
15.
Eur J Neurosci ; 12(5): 1687-95, 2000 May.
Artigo em Inglês | MEDLINE | ID: mdl-10792446

RESUMO

Loss of function mutations in the gene encoding the cysteine protease inhibitor, cystatin B (CSTB), are responsible for the primary defect in human progressive myoclonus epilepsy (EPM1). CSTB inhibits the cathepsins B, H, L and S by tight reversible binding, but little is known regarding its localization and physiological function in the brain and the relation between the depletion of the CSTB protein and the clinical symptoms in EPM1. We have analysed the expression of mRNA and protein for CSTB in the adult rat brain using in situ hybridization and immunocytochemistry. In the control brains, the CSTB gene was differentially expressed with the highest levels in the hippocampal formation and reticular thalamic nucleus, and moderate levels in amygdala, thalamus, hypothalamus and cortical areas. Detectable levels of CSTB were found in virtually all forebrain neurons but not in glial cells. Following 40 rapidly recurring seizures evoked by hippocampal kindling stimulations, CSTB mRNA expression showed marked bilateral increases in the dentate granule cell layer, CA1 and CA4 pyramidal layers, amygdala, and piriform and parietal cortices. Maximum levels were detected at 6 or 24 h, and expression had reached control values at 1 week post-seizures. The changes of mRNA expression were accompanied by transient elevations (at 6-24 h) of CSTB protein in the same brain areas. These findings demonstrate that seizure activity leads to rapid and widespread increases of the synthesis of CSTB in forebrain neurons. We propose that the upregulation of CSTB following seizures may counteract apoptosis by binding cysteine proteases.


Assuntos
Encéfalo/metabolismo , Cistatinas/genética , Epilepsias Mioclônicas/genética , Regulação da Expressão Gênica , Hipocampo/metabolismo , Neurônios/metabolismo , Convulsões/genética , Transcrição Gênica , Animais , Catepsinas/antagonistas & inibidores , Cistatina B , Cistatinas/análise , Cistatinas/metabolismo , Inibidores de Cisteína Proteinase/genética , Giro Denteado/metabolismo , Lateralidade Funcional , Humanos , Excitação Neurológica , Masculino , Especificidade de Órgãos , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Convulsões/metabolismo
16.
Biochem Mol Med ; 62(1): 26-35, 1997 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-9367795

RESUMO

We examined the type I collagen synthesized by cultured dermal fibroblasts from a patient affected with osteogenesis imperfecta (OI) type IV. Both normal and abnormal trimers were produced. The mutant collagen molecules were excessively modified intracellularly, had a melting temperature 4 degrees C lower than the control, were secreted at a reduced rate, and underwent delayed processing to mature alpha chains.Molecular investigations identified a G --> A transition in one COL1A2 allele, resulting in a Gly922 --> Ser substitution in the alpha2(I) chain. The proband's mutation was demonstrated to arise "de novo" by the absence of the mutant allele restriction enzyme pattern from parental genomic DNA.We analyzed the insoluble extracellular matrix deposited by long-term cultured fibroblasts from our patient and from a previously described unrelated individual who carries an identical substitution. In both cases, the mutant chain constituted 10-15% of the total alpha chains deposited.We also present here the first detailed comparison of phenotype between unrelated OI patients with an identical collagen mutation. These two patients are both Caucasian females, ages 8 and 9 years, each diagnosed as type IV OI by the Sillence classification. They have a similar phenotype including moderate skeletal fragility with several femur fractures, dentinogenesis imperfecta, wormian bone, and reduced height and weight. We conclude that this phenotype is related both to the location of this mutation and to the similar extent of matrix incorporation by the mutant chains. Molecular and biochemical studies of unrelated individuals with identical amino acid substitutions in type I collagen resulting in either similar or dissimilar clinical outcomes will make a significant contribution to identifying the factors involved in the modulation of the OI phenotype.


Assuntos
Colágeno/metabolismo , Mutação , Osteogênese Imperfeita/genética , Células Cultivadas , Criança , Feminino , Humanos , Fenótipo
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