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1.
Eur J Pediatr ; 173(3): 361-6, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24114256

RESUMO

UNLABELLED: Pyruvate carboxylase (PC) deficiency (OMIM 266150) is an autosomal recessive disorder that usually presents with lactic acidaemia and severe neurological dysfunction, leading to death in infancy. Because the enzyme is involved in gluconeogenesis and anaplerosis of the Krebs cycle, therapeutic strategies have included avoiding fasting and attempts to correct the defect of anaplerosis. Triheptanoin is a triglyceride of C7 fatty acids. The oxidation of odd chain fatty acids leads to the production not only of acetyl-CoA but also of propionyl-CoA, which is an anaplerotic substrate for the Krebs cycle. One infant with PC deficiency has previously been treated with triheptanoin as well as citrate and 2-chloropropionate. We report two further patients with PC deficiency, who were treated with triheptanoin, continuously from 11 and 21 days of age. They were also given citrate, aspartate and dichloroacetate. Triheptanoin did not lead to any clinical or biochemical improvement. The plasma and CSF lactate concentrations remained high with episodes of severe ketoacidosis and lactic acidosis. Both patients had severe hearing loss, roving eye movements, seizures and very limited neurodevelopmental progress; they died at the ages of 7 and 8 months. CONCLUSION: Though triheptanoin did not alter the clinical course in our patients, it was well tolerated. It remains possible that less severely affected patients might benefit from this form of therapy.


Assuntos
Doença da Deficiência de Piruvato Carboxilase/tratamento farmacológico , Triglicerídeos/uso terapêutico , Feminino , Humanos , Recém-Nascido , Resultado do Tratamento
2.
Clin Exp Dermatol ; 36(1): 88-90, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21188847

RESUMO

Erythrokeratoderma variabilis (EKV) is characterized by fixed hyperkeratotic plaques and transient erythema. Mutations in the genes GJB3 and GJB4, which encode connexin (Cx)31 and Cx30.3, are associated with EKV. We report one novel mutation in Cx31 and one recurrent mutation in Cx30.3 in two different families. One novel rare sequence variant of unknown clinical significance was also identified. This finding extends the spectrum of known EKV-associated mutations.


Assuntos
Conexinas/genética , Eritroceratodermia Variável/genética , Mutação/genética , Adolescente , Adulto , Análise Mutacional de DNA , Eritroceratodermia Variável/patologia , Feminino , Predisposição Genética para Doença , Humanos , Linhagem , Adulto Jovem
3.
J Exp Med ; 183(5): 2087-95, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8642319

RESUMO

Structural studies of cellular receptor molecules involved in immune recognition require the production of large quantities of the extracellular domains of these glycoproteins. The murine major histocompatibility complex (MHC) class II-restricted response has been extensively studied by functional means, but the engineering and purification of the native, empty form of the most-studied murine MHC class II molecule, IA, has been difficult to achieve. IA molecules, which are the murine equivalent of human histocompatibility leukocyte antigen-DQ molecules, have a low efficiency of chain pairing, which results in poor transport to the cell surface and in the appearance of mixed isotype pairs. We have engineered soluble IA molecules whose pairing has been forced by the addition of leucine zipper peptide dimers at their COOH-terminus. The molecules are secreted "empty" into the extracellular medium and can be loaded with single peptide after purification. These IA molecules have been expressed in milligram quantity for crystallization as well as for activation of T cells and measurement of MHC class II-T cell receptor interactions.


Assuntos
Antígenos de Histocompatibilidade Classe II/biossíntese , Linfócitos T/imunologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Células Cultivadas , Primers do DNA , DNA Complementar , Drosophila melanogaster , Antígenos HLA-DQ/imunologia , Antígenos de Histocompatibilidade Classe II/imunologia , Antígenos de Histocompatibilidade Classe II/isolamento & purificação , Humanos , Cinética , Zíper de Leucina , Camundongos , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Receptores de Antígenos de Linfócitos T/biossíntese , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/isolamento & purificação , Trombina , Transfecção
4.
J Neurol Neurosurg Psychiatry ; 81(7): 716-8, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20478848

RESUMO

BACKGROUND: Epilepsy carries an increased risk of premature death. For some people with intractable focal epilepsy, surgery offers hope for a seizure-free life. The authors aimed to see whether epilepsy surgery influenced mortality in people with intractable epilepsy. METHODS: The authors audited survival status in two cohorts (those who had surgery and those who had presurgical assessment but did not have surgery). RESULTS: There were 40 known deaths in the non-surgical group (3365 person years of follow-up) and 19 in the surgical group (3905 person-years of follow-up). Non-operated patients were 2.4 times (95% CI 1.4 to 4.2) as likely to die as those who had surgery. They were 4.5 times (95% CI 1.9 to 10.9) as likely to die a probable epilepsy-related death. In the surgical group, those with ongoing seizures 1 year after surgery were 4.0 (95% CI 1.2 to 13.7) times as likely to die as those who were seizure-free or who had only simple partial seizures. Time-dependent Cox analysis showed that the yearly outcome group did not significantly affect mortality (HR 1.3, 95% CI 0.9 to 1.8). CONCLUSION: Successful epilepsy surgery was associated with a reduced risk of premature mortality, compared with those with refractory focal epilepsy who did not have surgical treatment. To some extent, the reduced mortality is likely to be conferred by inducing freedom from seizures. It is not certain whether better survival is attributable only to surgery, as treatment decisions were not randomised, and there may be inherent differences between the groups.


Assuntos
Epilepsias Parciais/mortalidade , Epilepsias Parciais/cirurgia , Adolescente , Adulto , Estudos de Coortes , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos , Análise de Regressão , Convulsões/epidemiologia , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
5.
Science ; 288(5465): 505-11, 2000 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-10775108

RESUMO

Susceptibility to murine and human insulin-dependent diabetes mellitus correlates strongly with major histocompatibility complex (MHC) class II I-A or HLA-DQ alleles that lack an aspartic acid at position beta57. I-Ag7 lacks this aspartate and is the only class II allele expressed by the nonobese diabetic mouse. The crystal structure of I-Ag7 was determined at 2.6 angstrom resolution as a complex with a high-affinity peptide from the autoantigen glutamic acid decarboxylase (GAD) 65. I-Ag7 has a substantially wider peptide-binding groove around beta57, which accounts for distinct peptide preferences compared with other MHC class II alleles. Loss of Asp(beta57) leads to an oxyanion hole in I-Ag7 that can be filled by peptide carboxyl residues or, perhaps, through interaction with the T cell receptor.


Assuntos
Diabetes Mellitus Tipo 1/imunologia , Genes MHC da Classe II , Antígenos de Histocompatibilidade Classe II/química , Alelos , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Ácido Aspártico/química , Cristalografia por Raios X , Drosophila melanogaster , Glutamato Descarboxilase/metabolismo , Antígenos de Histocompatibilidade Classe II/genética , Antígenos de Histocompatibilidade Classe II/metabolismo , Humanos , Ligação de Hidrogênio , Camundongos , Camundongos Endogâmicos NOD , Modelos Moleculares , Dados de Sequência Molecular , Biblioteca de Peptídeos , Ligação Proteica , Conformação Proteica , Estrutura Secundária de Proteína , Receptores de Antígenos de Linfócitos T/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo
6.
Dev Biol (Basel) ; 131: 377-85, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18634499

RESUMO

Ketamine was one of the therapeutic agents used as a therapy for a human rabies survivor who did not receive rabies vaccine. Ketamine therapy is re-examined here in infected mouse primary neuron cultures and in adult ICR mice using the CVS strain with both intracerebral and peripheral routes of inoculation with ketamine vs. vehicle given intraperitoneally. No significant beneficial therapeutic effects of ketamine in the cultures or mouse model were observed. This team does not recommend further widespread clinical use of ketamine on human rabies patients until further experimental work demonstrates therapeutic efficacy. Because of the potential neuroprotective and anti-apoptotic properties of minocycline, minocycline therapy was assessed in infected primary neuron cultures and in neonatal ICR mice infected by peripheral inoculation with a highly attenuated rabies virus strain. No beneficial effect of minocycline was observed in the primary neuron cultures. In the mouse model, minocycline therapy aggravated the clinical neurological disease and resulted in higher mortality. An anti-apoptotic effect of minocycline was noted in the brains of infected mice, which may have very mildly increased viral spread. An anti-inflammatory effect was also noted in the brain using a CD3 T cell marker. These effects likely aggravated the disease. This team recommends that empirical therapy with minocycline be avoided in the management of rabies and viral encephalitis in humans until more information becomes available.


Assuntos
Modelos Animais de Doenças , Ketamina/uso terapêutico , Neurônios/citologia , Raiva/tratamento farmacológico , Animais , Apoptose , Feminino , Humanos , Camundongos , Camundongos Endogâmicos ICR , Minociclina/efeitos adversos , Minociclina/uso terapêutico , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Vírus da Raiva/efeitos dos fármacos , Vírus da Raiva/patogenicidade , Resultado do Tratamento
7.
Clin Exp Rheumatol ; 25(2): 246-51, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17543149

RESUMO

OBJECTIVE: Sporadic inclusion body myositis (s-IBM) is a chronic, progressive, inflammatory myopathy of unknown aetiology, generally resistant to immunosuppressive therapy. Given that lymphocyte infiltrates in s-IBM muscle tissue are CD8+ T cells, targeting these cells may represent a valid approach. PATIENTS AND METHODS: Three patients with biopsy-proven s-IBM, high creatine kinase levels at diagnosis, two of whom with associated immune disorders, were treated with either cyclosporin-A (CyA) or tacrolimus, in combination with high doses of corticosteroids (CS), followed by rapid CS tapering. Clinical assessment and laboratory evaluation were performed every three months for the first year and then every six months for the second year. RESULTS: Based on muscle strength assessment and muscle enzyme serum levels, a major clinical response was observed at month +3 in two out of the three patients. A complete clinical response and major clinical response were obtained at month +6, in two and one patient, respectively. Normalization of serum muscle enzymes was observed in all. Steroids could be tapered to very low doses in all patients and were suspended early in one. Laboratory, but not clinical relapse occurred in one patient and was controlled by increasing the CyA dose. Treatment was well tolerated, with no serious adverse events occurring. All three patients are maintaining immunosuppressive therapy. CONCLUSION: Calcineurin inhibitors may represent a useful option for the long-term management of s-IBM, possibly in a subset characterized by a short duration with high disease activity or associated autoimmune manifestations.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Ciclosporina/uso terapêutico , Imunossupressores/uso terapêutico , Miosite de Corpos de Inclusão/tratamento farmacológico , Miosite de Corpos de Inclusão/imunologia , Tacrolimo/uso terapêutico , Corticosteroides/uso terapêutico , Idoso , Inibidores de Calcineurina , Ciclosporina/efeitos adversos , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Humanos , Imunossupressores/efeitos adversos , Pessoa de Meia-Idade , Músculo Esquelético/enzimologia , Músculo Esquelético/fisiopatologia , Tacrolimo/efeitos adversos , Fatores de Tempo , Resultado do Tratamento
8.
J Neurol Neurosurg Psychiatry ; 77(9): 1076-8, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16914756

RESUMO

AIM: To determine the effects of sleep and wakefulness on seizures in patients with refractory epilepsy recorded while undergoing video-electroencephalography (EEG) telemetry. METHODS: The video-EEG data of patients who had two or more seizures during video-EEG telemetry (n = 270) were reviewed. Fifty seven patients who had seizures both in wakefulness and sleep were identified. The video and ictal EEG data were reviewed, paying specific attention to type of seizures, duration, semiology, lateralisation and number of seizures. RESULTS: Three hundred and sixty two seizures were recorded; 237 seizures while awake and 125 while sleeping. Secondary generalisation occurred more often in sleep than in wakefulness (p < 0.01). Overall, there was no significant effect of sleep on the duration of seizures or ictal EEG change. Sleep and awake seizures differed in only eight patients. CONCLUSION: Secondary generalisation occurred more often in sleep than in wakefulness, perhaps due to the facilitated spread of seizures during sleep. For the most part, however, seizures recorded during sleep did not differ from those recorded during wakefulness.


Assuntos
Convulsões/fisiopatologia , Sono REM/fisiologia , Vigília/fisiologia , Resistência a Medicamentos , Eletroencefalografia , Epilepsia do Lobo Frontal/fisiopatologia , Epilepsia do Lobo Temporal/fisiopatologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Gravação em Vídeo
9.
Water Sci Technol ; 53(10): 83-90, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16838692

RESUMO

Evapotranspiration (ET) from irrigated land is one of the most useful indicators to explain whether the water is used as "intended". In this study, the Surface Energy Balance Algorithm for Land (SEBAL) was used to compute actual ET from a Landsat7 image of December 29, 2000 for diverse land use in the Krishna Basin in India. SEBAL ETa varies between 0 to 4.7 mm per day over the image and was quantified for identified land use classes. Seasonal/annual comparison of ETa from different land uses requires time series images, processed by SEBAL. In this study, the Landsat-derived snapshot SEBAL ETa result was interpreted using the cropping calendar and time series analysis of MODIS imagery. The wastewater irrigated area in the basin has the highest ETa in the image, partly due to its advanced growth stage compared to groundwater-irrigated rice. Shrub and forests in the senescence phase have similar ETa to vegetable/cash crops, and ETa from grasslands is a low 0.8 mm per day after the end of the monsoon. The results indicate that wastewater irrigation of fodder and rice is sufficient to meet crop water demand but there appears to be deficit irrigation of rice using groundwater.


Assuntos
Produtos Agrícolas , Abastecimento de Água , Algoritmos , Índia , Rios , Comunicações Via Satélite , Eliminação de Resíduos Líquidos , Tempo (Meteorologia)
10.
J Neurosci ; 19(11): 4449-61, 1999 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-10341246

RESUMO

During cortical development, embryonic neurons migrate from germinal zones near the ventricle into the cortical plate, where they organize into layers. Mechanisms that direct neuronal migration may include molecules that act as chemoattractants. In rats, GABA, which localizes near the target destination for migrating cortical neurons, stimulates embryonic neuronal migration in vitro. In mice, glutamate is highly localized near the target destinations for migrating cortical neurons. Glutamate-induced migration of murine embryonic cortical cells was evaluated in cell dissociates and cortical slice cultures. In dissociates, the chemotropic effects of glutamate were 10-fold greater than the effects of GABA, demonstrating that for murine cortical cells, glutamate is a more potent chemoattractant than GABA. Thus, cortical chemoattractants appear to differ between species. Micromolar glutamate stimulated neuronal chemotaxis that was mimicked by microM NMDA but not by other ionotropic glutamate receptor agonists (AMPA, kainate, quisqualate). Responding cells were primarily derived from immature cortical regions [ventricular zone (vz)/subventricular zone (svz)]. Bromodeoxyuridine (BrdU) pulse labeling of cortical slices cultured in NMDA antagonists (microM MK801 or APV) revealed that antagonist exposure blocked the migration of BrdU-positive cells from the vz/svz into the cortical plate. PCR confirmed the presence of NMDA receptor expression in vz/svz cells, whereas electrophysiology and Ca2+ imaging demonstrated that vz/svz cells exhibited physiological responses to NMDA. These studies indicate that, in mice, glutamate may serve as a chemoattractant for neurons in the developing cortex, signaling cells to migrate into the cortical plate via NMDA receptor activation.


Assuntos
Córtex Cerebral/efeitos dos fármacos , Ácido Glutâmico/farmacologia , Neurônios/efeitos dos fármacos , Receptores de N-Metil-D-Aspartato/efeitos dos fármacos , Animais , Contagem de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Córtex Cerebral/citologia , Córtex Cerebral/embriologia , Quelantes/farmacologia , Quimiotaxia/efeitos dos fármacos , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Desenvolvimento Embrionário e Fetal/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BL , Técnicas de Cultura de Órgãos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estimulação Química
11.
Protein Sci ; 7(2): 413-8, 1998 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9521118

RESUMO

Class II Major Histocompatibility (MHC) molecules are cell surface heterodimeric glycoproteins that play a central role in the immune response by presenting peptide antigens for surveillance by T cells. Due to the inherent instability of the class II MHC heterodimer, and its dependence on bound peptide for proper assembly, the production of electrophoretically pure samples of class II MHC proteins in complex with specific peptides has been problematic. A soluble form of the murine class II MHC molecule, I-Ad, with a leucine zipper tail added to each chain to enhance dimer assembly and secretion, has been produced in Drosophila melanogaster SC2 cells. To facilitate peptide loading, a high affinity ovalbumin peptide was covalently engineered to be attached by a six-residue linker to the amino terminus of the I-Adbeta chain. This modified I-Ad molecule was purified using preparative IEF and one fraction, after removal of the leucine zipper tails, produced crystals suitable for X-ray crystallographic analysis. The protein engineering and purification methods described here should be of general value for the expression of I-A and other class II MHC-peptide complexes.


Assuntos
Antígenos de Histocompatibilidade Classe II/química , Engenharia de Proteínas , Sequência de Aminoácidos , Animais , Linhagem Celular , Clonagem Molecular , Cristalografia por Raios X , Drosophila melanogaster/genética , Antígenos de Histocompatibilidade Classe II/genética , Camundongos , Dados de Sequência Molecular , Ovalbumina/química , Fragmentos de Peptídeos/química
12.
Cell Prolif ; 28(2): 73-84, 1995 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-7893841

RESUMO

The daily oral administration of 3 ml of two oils (So-5407 and So-1129) containing essential fatty acids (EFAs) for 16 weeks resulted in a transient increase in cell proliferative activity in the skin of female Large White pigs. The So-5407 oil contained 7% gamma-linolenic acid (GLA) whereas So-1129 was an oil of similar composition, but with no GLA. Hyperplasia of the epidermis was observed after the administration of both oils, and this was characterized by an increase in the size of the rete pegs. The maximum effect occurred at 4 weeks after the start of oil administration, at which time the number of viable cell layers had increased by a factor of approximately 1.5, and mean epidermal thickness (excluding the stratum corneum) was approximately 40% greater than that of the epidermis prior to oil administration. There was a marked increase in the labelling index (LI) of the basal cell layer of the epidermis in pigs receiving So-5407. Maximum LIs were quantified at 4 weeks after the start of administration and were 18.8 +/- 1.3% and 13.1 +/- 1.7% for pigs receiving So-5407 and So-1129, respectively. After this time the LI declined progressively and had returned to values within normal limits (P > 0.1) by 8 weeks after the start of administration of both oils. A similar pattern of change in the LI was seen in the follicular epithelium, although the peak values at 4 weeks after the start of oil administration of 12.2 +/- 1.8% and 10.8 +/- 0.9 for the groups receiving So-5407 and So-1129, respectively, were lower than in the epidermis. Labelled cells were also counted in the papillary dermis and maximum values were again seen at 4 weeks after the start of oil administration. Of the two oils, So-1129 had the greatest effect, with the number of labelled cells in the papillary dermis being a factor of three to four-fold higher than in skin prior to oil administration, between 2 and 12 weeks after the start of administration.


Assuntos
Ácidos Graxos Essenciais/farmacologia , Pele/efeitos dos fármacos , Animais , Ácido Eicosapentaenoico/efeitos adversos , Ácido Eicosapentaenoico/farmacologia , Epiderme/efeitos dos fármacos , Epiderme/patologia , Epitélio/efeitos dos fármacos , Epitélio/patologia , Ácidos Graxos Essenciais/efeitos adversos , Ácidos Graxos Essenciais/análise , Feminino , Cabelo/efeitos dos fármacos , Cabelo/patologia , Hiperplasia/induzido quimicamente , Hiperplasia/patologia , Ácidos Linoleicos/efeitos adversos , Ácidos Linoleicos/farmacologia , Pele/patologia , Suínos , Fatores de Tempo , Ácido gama-Linolênico/efeitos adversos , Ácido gama-Linolênico/análise , Ácido gama-Linolênico/farmacologia
13.
Int J Radiat Oncol Biol Phys ; 30(5): 1119-25, 1994 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-7961020

RESUMO

PURPOSE: To evaluate the possible role of essential fatty acids, specifically gamma-linolenic and eicosapentaenoic acid, in the amelioration of early and late radiation damage to the skin. METHODS AND MATERIALS: Skin sites on the flank of 22-25 kg female large white pigs were irradiated with either single or fractionated doses (20 F/28 days) of beta-rays from 22.5 mm diameter 90Sr/90Y plaques at a dose rate of approximately 3 Gy/min. Essential fatty acids were administered orally in the form of two 'active' oils, So-1100 and So-5407, which contained gamma-linolenic acid and a mixture of that oil with eicosapentaenoic acid, respectively. Oils (1.5-6.0 ml) were given daily for 4 weeks prior, both 4 weeks prior and 10-16 weeks after, or in the case of one single dose study, just for 10 weeks after irradiation. Control animals received a 'placebo' oil, So-1129, containing no gamma linolenic acid or eicosapentaenoic acid over similar time scales before and after irradiation. Acute and late skin reactions were assessed visually and the dose-related incidence of a specific reaction used to compare the effects of different treatment schedules. RESULTS: A reduction in the severity of both the early and late radiation reactions in the skin was only observed when 'active' oils were given over the time course of the expression of radiation damage. Prior treatment with oils did not modify the radiation reaction. A 3.0 ml daily dose of either So-1100 or So-5407 given prior to, but also after irradiation with single and fractionated doses of beta-rays produced the most significant modification to the radiation reactions, effects consistent with dose modification factors between 1.06-1.24 for the acute reactions of bright red erythema and/or moist desquamation, and of 1.14-1.35 for the late reactions of dusky/mauve erythema and dermal necrosis. There was the strong suggestion of an effect produced by the 'placebo' oil, So-1129, after higher daily doses of oil. CONCLUSIONS: Essential fatty acids can modulate normal tissue reactions when given over the time when radiation damage is normally expressed. Dose modification factors suggest that a > or = 10% higher dose is required to produce the same level of normal tissue injury. Clinical application of selected essential fatty acids at appropriate doses may lead to a significant increase in the therapeutic gain in patients treated for cancer by radiotherapy.


Assuntos
Ácido Eicosapentaenoico/farmacologia , Ácidos Graxos Essenciais/farmacologia , Ácidos Linoleicos/farmacologia , Lesões Experimentais por Radiação/prevenção & controle , Pele/efeitos da radiação , Ácido gama-Linolênico/farmacologia , Animais , Partículas beta , Feminino , Ácido Linoleico , Necrose , Lesões Experimentais por Radiação/patologia , Pele/efeitos dos fármacos , Pele/patologia , Estrôncio , Suínos , Radioisótopos de Ítrio
14.
Neuroscience ; 101(2): 377-91, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11074161

RESUMO

Limbic epilepsy is a chronic condition associated with a broad zone of seizure onset and pathology. Studies have focused mainly on the hippocampus, but there are indications that changes occur in other regions of the limbic system. This study used in vitro intracellular recording and histology to examine alterations to the physiology and anatomy of the basal nucleus of the amygdala in a rat model of chronic limbic epilepsy characterized by spontaneously recurring seizures. Epileptic pyramidal neuron responses evoked by stria terminalis stimulation revealed hyperexcitability characterized by multiple action potential bursts and no evident inhibitory potentials. In contrast, no hyperexcitability was observed in amygdalar neurons from kindled (included as a control for seizure activity) or control rats. Blockade of ionotropic glutamate receptors unmasked inhibitory postsynaptic potentials in epileptic pyramidal neurons. Control, kindled and epileptic inhibitory potentials were predominantly biphasic, with fast and slow components, but a few cells exhibited only the fast component (2/12 in controls, 0/3 in kindled, 3/10 in epileptic). Epileptic fast inhibitory potentials had a more rapid onset and shorter duration than control and kindled. Approximately 40% of control neurons exhibited spontaneous inhibitory potentials; no spontaneous inhibitory potentials were observed in neurons from kindled or epileptic rats. A preliminary histological examination revealed no gross alterations in the basal amygdala from epileptic animals. These results extend previous findings from this laboratory that hyperexcitability is found in multiple epileptic limbic regions and may be secondary to multiple alterations in excitatory and inhibitory efficacy. Because there were no differences between control and kindled animals, the changes observed in the epileptic animals are unlikely to be secondary to recurrent seizures.


Assuntos
Potenciais de Ação/fisiologia , Tonsila do Cerebelo/fisiopatologia , Epilepsia/fisiopatologia , Neurônios/fisiologia , Valina/análogos & derivados , Tonsila do Cerebelo/patologia , Animais , Modelos Animais de Doenças , Estimulação Elétrica/efeitos adversos , Epilepsia/patologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/fisiologia , Antagonistas GABAérgicos/farmacologia , Excitação Neurológica/fisiologia , Vias Neurais/patologia , Vias Neurais/fisiopatologia , Neurônios/classificação , Neurônios/citologia , Ácidos Fosfínicos/farmacologia , Propanolaminas/farmacologia , Quinoxalinas/farmacologia , Ratos , Valina/farmacologia
15.
Hum Pathol ; 29(5): 482-90, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9596272

RESUMO

DNA index (DI) values seen in 86 sporadic colorectal adenocarcinomas were related to clinical, morphological, and disease progression features. DI, whose overall distribution was bimodal with peaks in the diploid and from hypotriploid to tetraploid ranges, was related to pathological lymph node staging (pN), staging, lymphoid reaction, and tubular configuration. With increasing severity in pathological features, an irregular shift in DI class prevalence was seen, with no steady increase from diploidy to higher degrees of aneuploidy. All UICC stage I tumors (13% of total) were aneuploid, 50% being hypertriploid; diploidy (35%) and hypertriploidy (22%) prevailed in stage II carcinomas (41% of total), diploidy (35%) and hypotriploidy (30%) in stage III (30% of total), and triploidy (33%) in stage IV (15% of total). Amongst features related to stage (lymphoid reaction, depth of neoplastic embolization, grading, tubular configuration, and polymorphism), few were associated with DI, and none influenced DI shift and class prevalence through the stages. The biological capabilities of colorectal adenocarcinoma in relation to stage are expressed by certain aneuploid DI classes (hypertriploidy: absence of extracolonic spread; hypotriploidy: lymph node metastases; triploidy: distant metastases). Diploidy is unrelated to criteria defining stage above I and predicts 50% of cases with development of metachronous metastases. Irregular DI class shift through the stages may be attributable to different pathways of cancerogenesis and disease progression in diploid versus aneuploid carcinomas. Alternatively, assuming that the diploid fraction in aneuploid tumors contains neoplastic cells, pure diploid carcinomas represent the selection of a vital clone that may give rise to a further mixed population whose aneuploid DI is different and best fitted to express the biological capabilities of that given stage.


Assuntos
Adenocarcinoma/patologia , Neoplasias Colorretais/patologia , DNA de Neoplasias/genética , Índice Mitótico/genética , Adenocarcinoma/genética , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/genética , Neoplasias Colorretais/mortalidade , Progressão da Doença , Feminino , Citometria de Fluxo , Humanos , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Ploidias , Taxa de Sobrevida
16.
Am J Clin Pathol ; 113(4): 546-54, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10761457

RESUMO

Histologically detectable iron (HDI) and HFE mutations were searched for in liver biopsy specimens from 58 Italian patients with chronic hepatitis C, and morphologic features were compared to examine their reciprocal relation and their contribution to disease progression. HDI was evident in 48% of cases with features of nonhemochromatosis iron overload. Total, sinusoidal, and portal HDI increased with stage; grade was related to all iron scores because of the contribution of portal inflammation and interface hepatitis. HFE mutations were seen in 47% of patients with chronic hepatitis C and in 28% of control subjects; they were related to stage and the His63Asp mutation to portal HDI. On multivariate analysis, grade but not stage or HFE mutations was associated with HDI in all sites. Interface hepatitis with its sequelae (sinusoidal capillarization and microshunting) represents a major factor in iron deposition in chronic hepatitis C and justifies the features of HDI. HFE mutations are not responsible for HDI deposition but could favor the progression of virus-induced damage independently from interference with iron metabolism.


Assuntos
Antígenos HLA/genética , Hemocromatose/genética , Hepatite C Crônica/genética , Antígenos de Histocompatibilidade Classe I/genética , Ferro/metabolismo , Proteínas de Membrana , Mutação de Sentido Incorreto , Adolescente , Adulto , Idoso , Anticorpos Antivirais/análise , Progressão da Doença , Feminino , Hemocromatose/metabolismo , Hemocromatose/patologia , Proteína da Hemocromatose , Hepacivirus/genética , Hepacivirus/imunologia , Hepacivirus/isolamento & purificação , Hepatite C Crônica/metabolismo , Hepatite C Crônica/patologia , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Polimorfismo de Fragmento de Restrição , RNA Viral/análise , Reação em Cadeia da Polimerase Via Transcriptase Reversa
17.
J Clin Pathol ; 31(8): 761-4, 1978 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-690240

RESUMO

A pseudolymphomatous reaction involving subcutaneous tissue and underlying skeletal muscle is described in a woman who was receiving phenytoin sodium and phenobarbitone. The histological appearance was of nodular, densely cellular tissue composed of histiocytes, plasma cells, lymphocytes, fibroblasts, and occasional polymorphonuclear cells. The significance of this finding is briefly considered in relation to the existing literature.


Assuntos
Linfoma/induzido quimicamente , Fenitoína/efeitos adversos , Neoplasias de Tecidos Moles/induzido quimicamente , Adulto , Feminino , Humanos , Linfoma/patologia , Músculos/patologia , Fenitoína/uso terapêutico , Neoplasias de Tecidos Moles/patologia
18.
Environ Mol Mutagen ; 32(2): 173-8, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-9776180

RESUMO

Previously, we determined that elimination of deoxycytidylate (dCMP) deaminase (DCD1) in the yeast Saccharomyces cerevisiae increases the intracellular dCTP:dTTP ratio and reduces the induction of G x C --> A x T transitions in the SUP4-o gene by ethyl methanesulfonate (EMS) and N-methyl-N'-nitro-N-nitrosoguanidine (MNNG). Simultaneously, the G x C --> C x G transversion frequency rises substantially. We attributed the first response to dCTP outcompeting dTTP for incorporation opposite O6-alkylguanine, and the second outcome to the increased dCTP pool causing error-prone repair of apurinic (AP) sites resulting from the removal or lability of N7-alkylguanine. To test the latter hypothesis, we used isogenic dcd1 strains deleted for either of two genes (MAG1: 3-methyladenine glycosylase; APN1: apurinic endonuclease) involved in the repair of N7-alkylguanine. In these backgrounds, EMS or MNNG induction of total SUP4-o mutations, G x C --> A x T transitions and G x C --> C x G transversions were reduced by >98%, >97%, and >80%, respectively. Mutation frequencies in the dcd1 apn1 strain were close to those for spontaneous mutagenesis in the wild-type parent. These findings argue that misincorporation of dCTP during repair of alkylation-induced AP sites is responsible for the increased G x C --> C x G transversion frequency in the dcd1 strain treated with EMS or MNNG. The data also demonstrate that defective repair of AP sites coupled with an elevated dCTP:dTTP ratio eliminates most EMS and MNNG mutagenesis. In addition, the results point to a role for AP sites in the production of some EMS- and MNNG-induced G x C --> A x T transitions as well as other substitutions in the dcd1 strain.


Assuntos
Alquilantes/toxicidade , Carbono-Oxigênio Liases/fisiologia , DNA Glicosilases , DNA Ligases/fisiologia , Reparo do DNA , DNA Fúngico/efeitos dos fármacos , Nucleotídeos de Desoxicitosina/farmacologia , Metanossulfonato de Etila/antagonistas & inibidores , Proteínas Fúngicas/fisiologia , Metilnitronitrosoguanidina/toxicidade , Mutagênese/efeitos dos fármacos , N-Glicosil Hidrolases/fisiologia , Saccharomyces cerevisiae/efeitos dos fármacos , Alquilação , Carbono-Oxigênio Liases/deficiência , Carbono-Oxigênio Liases/genética , Adutos de DNA/metabolismo , Dano ao DNA , DNA Ligases/deficiência , DNA Ligases/genética , Reparo do DNA/efeitos dos fármacos , Reparo do DNA/genética , DNA Fúngico/genética , DNA Fúngico/metabolismo , DNA Liase (Sítios Apurínicos ou Apirimidínicos) , Desoxirribonuclease IV (Fago T4-Induzido) , Metanossulfonato de Etila/toxicidade , Proteínas Fúngicas/genética , Genes Supressores/efeitos dos fármacos , Líquido Intracelular , N-Glicosil Hidrolases/deficiência , N-Glicosil Hidrolases/genética
19.
AJNR Am J Neuroradiol ; 20(7): 1259-67, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10472983

RESUMO

BACKGROUND AND PURPOSE: T1-, T2-, and proton density (PD)-weighted sequences are used to characterize the content of cystic intracranial lesions. Fluid-attenuated inversion recovery (FLAIR) MR sequences produce T2-weighted images with water signal saturation. Therefore, we attempted to verify whether FLAIR, as compared with conventional techniques, improves the distinction between intracranial cysts with a free water-like content versus those filled with a non-free water-like substance and, consequently, aids in the identification of these lesions as either neoplastic/inflammatory or maldevelopmental/porencephalic. METHODS: Forty-five cystic intracranial lesions were studied using T1-weighted, T2-weighted, FLAIR, and PD-weighted sequences. By means of clustering analysis of the ratio in signal intensity between the cystic intracranial lesions and CSF, the intracranial lesions were classified as filled with a free water-like content or with a non-free water-like substance. The results were compared with their true content as evaluated either histologically or on the basis of clinical, neuroradiologic, and follow-up features (necrotic material, 13 cases; accumulation of intercellular proteinaceous/myxoid material, eight cases; keratin, five cases; CSF, 19 cases). Cystic intracranial lesions were divided into two clinical groups, neoplastic/inflammatory and maldevelopmental/porencephalic, to evaluate the level of accuracy of each MR technique. The difference in absolute value signal intensity between CSF and cystic intracranial lesion content was calculated on FLAIR and PD-weighted images. RESULTS: PD-weighted and FLAIR sequences, unlike T1- and T2-weighted sequences, accurately depicted all cystic intracranial lesions containing necrotic or myxoid/proteinaceous intercellular material (non-free water-like) and most CSF-containing cystic intracranial lesions (free water-like). All imaging techniques inaccurately showed some of the keratin-containing cystic intracranial lesions and pineal cysts. The overall error rate was 22% for T1-weighted, 27% for T2-weighted, 9% for FLAIR, and 13% for PD-weighted sequences. The signal intensity difference between CSF and cystic intracranial lesion content was higher with FLAIR imaging. CONCLUSIONS: FLAIR imaging depicts far more accurately the content of cystic intracranial lesions and better reveals the distinction between maldevelopmental/porencephalic and neoplastic/inflammatory lesions than do conventional sequences. FLAIR has the added advantage of a higher signal intensity difference between cystic intracranial lesions and CSF.


Assuntos
Encefalopatias/diagnóstico , Cistos/diagnóstico , Imageamento por Ressonância Magnética , Adulto , Idoso , Idoso de 80 Anos ou mais , Encéfalo/patologia , Encefalopatias/classificação , Neoplasias Encefálicas/classificação , Neoplasias Encefálicas/diagnóstico , Análise por Conglomerados , Cistos/classificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
20.
Clin Chim Acta ; 304(1-2): 49-55, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11165198

RESUMO

Serum iron indices are believed to be elevated in patients with hepatitis C virus (HCV) infection in connection to the presence of hepatic inflammation, though this hypothesis has never been formally tested. We studied 69 consecutive, unselected anti HCV antibody positive patients, aged 14 to 70 years. Iron, transferrin saturation and ferritin were measured in fasting serum samples. Histologically detectable iron (HDI) as well as histologic grading and staging were estimated semiquantitatively in liver biopsy samples. The median values for serum iron, transferrin saturation and serum ferritin were 24 micromol/l (range, 8-61), 29 percent (range, 6-77) and 170 microg/l (range, 1-954), respectively. At univariate analysis, all three serum iron indices were positively correlated with grading and staging scores, as well as with HDI in the liver; only serum iron was positively correlated with transaminases. At multivariate analysis, independent associations were found between serum iron and the grading score; ferritin and sinusoidal and portal HDI; transferrin saturation and total hepatic HDI. In conclusion, in hepatitis C, serum iron reflects the degree of current hepatic inflammation and necrosis, whereas the extent of progressive deposition of iron in sites of fibrosis is best reflected by serum ferritin. Transferrin saturation is the best predictor of the status of hepatic iron deposits.


Assuntos
Hepatite C Crônica/sangue , Ferro/sangue , Adolescente , Adulto , Idoso , Feminino , Ferritinas/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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