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1.
J Affect Disord ; 314: 185-192, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-35817305

RESUMO

BACKGROUND: Patients with MDD may experience diverse residual symptoms after clinical response to antidepressant treatment. Among these symptoms, cognitive problems in executive functioning are prominent and make functional recovery largely an unmet need for MDD patients. In this study we assessed cognitive symptoms and functional impairment in patients with MDD responding to antidepressant treatment. METHODS: This was a national, multi-site, non-interventional, cross-sectional study of depressive symptomatology, cognitive performance and psychosocial functioning in Greek outpatients with MDD who had clinically responded to antidepressant treatment. Both clinician- and patient- rated measures were employed. Symptom remission was assessed with the Montgomery Asberg Depression Rating Scale (MADRS) total score (≤12) and functional recovery was assessed with the Sheehan Disability Scale (SDS) score (<6). RESULTS: 335 MDD patients participated in the study. After antidepressant monotherapy approximately 60 % of responders and 40 % of remitted patients did not meet the functional recovery criterion. More than 60 % of responders had concentration difficulties as assessed by MADRS item. Patient reported cognitive symptoms were statistically significantly associated with functionality (ß coefficient = 0.126, p-value = 0.027). LIMITATIONS: Non-interventional study design and lack of a control group or active comparator/reference. CONCLUSIONS: This study highlights the persistence of decreased cognitive performance, particularly in executive functioning in patients with MDD who have shown response and/or remission to antidepressant treatment. This appears to contribute to psychosocial functional impairment. Patient-reported cognitive and psychosocial functioning impairment should be included in routine clinical monitoring of outcomes in MDD treatments.


Assuntos
Transtorno Depressivo Maior , Antidepressivos/uso terapêutico , Cognição , Estudos Transversais , Transtorno Depressivo Maior/complicações , Transtorno Depressivo Maior/diagnóstico , Transtorno Depressivo Maior/tratamento farmacológico , Grécia , Humanos , Pacientes Ambulatoriais/psicologia
2.
Transl Psychiatry ; 7(5): e1137, 2017 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-28534874

RESUMO

Currently, there are no effective pharmacologic treatments for the core symptoms of autism spectrum disorder (ASD). There is, nevertheless, potential for progress. For example, recent evidence suggests that the excitatory (E) glutamate and inhibitory (I) GABA systems may be altered in ASD. However, no prior studies of ASD have examined the 'responsivity' of the E-I system to pharmacologic challenge; or whether E-I modulation alters abnormalities in functional connectivity of brain regions implicated in the disorder. Therefore, we used magnetic resonance spectroscopy ([1H]MRS) to measure prefrontal E-I flux in response to the glutamate and GABA acting drug riluzole in adult men with and without ASD. We compared the change in prefrontal 'Inhibitory Index'-the GABA fraction within the pool of glutamate plus GABA metabolites-post riluzole challenge; and the impact of riluzole on differences in resting-state functional connectivity. Despite no baseline differences in E-I balance, there was a significant group difference in response to pharmacologic challenge. Riluzole increased the prefrontal cortex inhibitory index in ASD but decreased it in controls. There was also a significant group difference in prefrontal functional connectivity at baseline, which was abolished by riluzole within the ASD group. Our results also show, for we believe the first time in ASD, that E-I flux can be 'shifted' with a pharmacologic challenge, but that responsivity is significantly different from controls. Further, our initial evidence suggests that abnormalities in functional connectivity can be 'normalised' by targeting E-I, even in adults.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Encéfalo/fisiopatologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Córtex Pré-Frontal/fisiopatologia , Riluzol/farmacologia , Adulto , Transtorno do Espectro Autista/diagnóstico por imagem , Transtorno do Espectro Autista/tratamento farmacológico , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Mapeamento Encefálico/métodos , Antagonistas de Aminoácidos Excitatórios/administração & dosagem , Antagonistas de Aminoácidos Excitatórios/metabolismo , Neuroimagem Funcional/métodos , Ácido Glutâmico/metabolismo , Ácido Glutâmico/fisiologia , Humanos , Espectroscopia de Ressonância Magnética/métodos , Masculino , Vias Neurais/fisiopatologia , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Riluzol/administração & dosagem , Riluzol/metabolismo , Ácido gama-Aminobutírico/metabolismo , Ácido gama-Aminobutírico/fisiologia
3.
Blood Cancer J ; 7(2): e533, 2017 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-28212373

RESUMO

Poly (ADP-ribose) polymerase 1 (PARP-1) has a central role in the repair of DNA breaks and is a promising treatment target in malignancy. We measured PARP1 mRNA levels by a SYBR-green-based PCR in the bone marrow of 74 patients with myelodysplastic syndrome (MDS) and correlated them to their demographic, hematologic and prognostic characteristics. The median PARP1 mRNA levels were correlated to the type of MDS (2008/2016 WHO classification, P=0.005) and to the IPSS score (P=0.002). A correlation was also found with the IPSS-R score (P=0.011) and the cytogenetic risk (P=0.008). In all cases, higher PARP1 levels were correlated with a higher risk category. Moreover, we found a significant survival disadvantage for patients with high PARP1 levels (median survival of 37.4 months versus 'not reached' for low PARP1 levels, P=0.0001, and a 5-year survival rate of 29.8 versus 88.9%, respectively). PARP1 mRNA levels were found to be the stronger predictor of survival in multivariate analysis. These correlations have never been reported in the past and may render PARP1 a prognostic factor to be incorporated in the current prognostic systems for MDS, also laying the basis for clinical trials evaluating PARP1 inhibitors in higher-risk MDS.


Assuntos
Síndromes Mielodisplásicas/genética , Poli(ADP-Ribose) Polimerase-1/genética , RNA Mensageiro/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
4.
Pharmacol Biochem Behav ; 124: 58-66, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24867078

RESUMO

Endogenous and exogenous cannabinoids modulate learning and memory primarily via the cannabinoid type 1 receptor (CB1R). A variety of experimental procedures has focused on the role of CB1R in various aspects of learning and memory processes. However, the picture still remains unclear as there is a lack of information on the effects of relatively low doses of CB1R agonists in relation to their effects on locomotion. The present study sought to investigate CB1R activation, using a range of relatively low doses of the CB1R agonist WIN55,212-2, on multiple aspects of learning and memory in rats. For this purpose, non-associative learning was examined using the habituation of locomotion paradigm, recognition memory was evaluated with the novel object recognition task, and the radial water maze test was selected to assess rats' spatial memory. The ability of the CB1R antagonist, SR141716A, to counteract WIN55,212-2-induced behavioral effects was also tested. WIN55,212-2 (0.3, but not 0.03 or 0.1mg/kg) disrupted non-associative learning, different aspects of short- and long-term recognition memory (storage and retrieval) and retention of spatial memory. The 0.3mg/kg dose of WIN55,212-2 also decreased ambulatory, but not vertical (rearing), activity in non-habituated rats. These effects appeared to be CB1R dependent since pretreatment with SR141716A (0.03 mg/kg) prevented the WIN55,212-2-induced behavioral effects. The present findings further support and extend the complex impact of exogenous cannabinoids on learning and memory in relation to their effects on locomotion.


Assuntos
Benzoxazinas/farmacologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Receptor CB1 de Canabinoide/efeitos dos fármacos , Memória Espacial/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Masculino , Ratos , Ratos Sprague-Dawley
5.
Behav Brain Res ; 270: 261-9, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24867330

RESUMO

The cannabinoid system plays a regulatory role in neurotransmission and is involved in the central actions of psychostimulants. This complex interaction between the cannabinoid system and psychostimulants represents a potential pharmacological target for psychosis and addiction. However, most studies have focused on cocaine, therefore, it is unclear whether these findings can be extended to other psychostimulants such as the amphetamines. The present study investigated the effects of WIN55,212-2, a synthetic cannabinoid and SR141716A, a CB1 receptor antagonist, on D-amphetamine-induced locomotor activity and extracellular dopamine and glutamate release in the striatum. Rats were either observed for locomotor activity or glutamate and dopamine neurotransmitter release in the striatum using in vivo microdialysis following intraperitoneal co-administration of D-amphetamine with WIN55,212-2 or SR141716A. Our results demonstrated that d-amphetamine per se induced hyperlocomotion and enhanced dopamine and glutamate release, as expected. WIN55,212-2 dampened these effects when co-administered with d-amphetamine, while alone it displayed its characteristic biphasic motor profile coupled with increases in dopamine and decreases in glutamate release. SR141716A at high doses reduced D-amphetamine-induced hyperlocomotion and completely reversed enhanced dopamine and glutamate release but alone had no effect. These findings validate the capacity of the cannabinoid system to modulate amphetamine-induced behaviour and its neurochemical output, in a state-dependent manner, providing insight into aspects of the neurobiological substrate that underlies amphetamines' psychotogenic and addictive properties.


Assuntos
Anfetamina/farmacologia , Canabinoides/metabolismo , Corpo Estriado/efeitos dos fármacos , Dopamina/análise , Ácido Glutâmico/análise , Transmissão Sináptica/efeitos dos fármacos , Anfetamina/administração & dosagem , Animais , Benzoxazinas/administração & dosagem , Benzoxazinas/farmacologia , Antagonistas de Receptores de Canabinoides/administração & dosagem , Antagonistas de Receptores de Canabinoides/farmacologia , Estimulantes do Sistema Nervoso Central/administração & dosagem , Estimulantes do Sistema Nervoso Central/farmacologia , Corpo Estriado/metabolismo , Quimioterapia Combinada , Masculino , Microdiálise , Morfolinas/administração & dosagem , Morfolinas/farmacologia , Atividade Motora/efeitos dos fármacos , Naftalenos/administração & dosagem , Naftalenos/farmacologia , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Pirazóis/administração & dosagem , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Rimonabanto
7.
Behav Brain Res ; 224(1): 65-72, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21645556

RESUMO

Endocannabinoids are involved in excitatory neurotransmission initiated by glutamate and aspartate. The aim of the present study was to investigate the effects of the cannabinoid agonists, Δ(9)-THC and WIN55,212-2, on tissue (prefrontal cortex, dorsal striatum, nucleus accumbens, hippocampus, amygdala and hypothalamus) levels of glutamate and aspartate in two rat phenotypes, high responders (HR) and low responders (LR), differentiated according to their response to a novel environment. HR displayed increased motor activity but no difference in basal levels of glutamate and aspartate as compared to LR. Both cannabinoids increased ambulatory activity at the low doses, this effect was observed only in HR following Δ(9)-THC, but in both HR and LR following WIN55,212-2. The cannabinoids primarily increased glutamate levels in the prefrontal cortex, dorsal striatum, nucleus accumbens and hippocampus, while the high dose of WIN55,212-2 decreased glutamate levels in the amygdala and both doses in the hypothalamus; these effects appeared overall more pronounced in HR. In contrast, the cannabinoids primarily decreased aspartate levels in all brain regions, except in the dorsal striatum, where an increase was seen after both doses of Δ(9)-THC and WIN55,212-2 as well as in the nucleus accumbens after the low dose of Δ(9)-THC in HR; these effects also appeared overall more pronounced in HR. Present results show that exogenous cannabinoids affect tissue levels of glutamate and aspartate in a phenotype-, compound-, dose-, and brain region-dependent manner.


Assuntos
Analgésicos/farmacologia , Benzoxazinas/farmacologia , Encéfalo/efeitos dos fármacos , Dronabinol/farmacologia , Aminoácidos Excitatórios/metabolismo , Hipercinese/patologia , Morfolinas/farmacologia , Naftalenos/farmacologia , Análise de Variância , Animais , Encéfalo/metabolismo , Encéfalo/patologia , Relação Dose-Resposta a Droga , Masculino , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley
8.
Dement Geriatr Cogn Disord ; 32(4): 267-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22237255

RESUMO

BACKGROUND/AIMS: Results from German and Greek non-interventional studies were compared to investigate possible differences concerning efficacy, tolerability and compliance between both countries. METHODS: In two open-label, multicentre, non-interventional studies, 4,305 patients with mild to severe Alzheimer's disease (AD) were treated with daily doses of 20 mg memantine for 6 months. Efficacy was assessed using the Mini-Mental State Examination (MMSE) and instrumental activities of daily living (IADL) scales. Safety and tolerability were recorded. RESULTS: After 6 months, the patients showed an improvement of their cognitive performance by 2 MMSE points compared to baseline (p < 0.001). MMSE values were improved in 67.4% of the patients, while 15.1% remained stable, and MMSE deteriorated in 17.5% only. The ability to perform IADL increased, as is indicated by lower values (baseline: 70.5; after 6 months: 66.6 points). Improvement of cognition and IADL was nearly identical in both countries. Treatment discontinuation was significantly more frequent in the Greek population, mainly due to non-adherence (9.4% of the safety population). 345 adverse events were recorded in 245 patients (6.3%), and they were significantly associated with country and age. CONCLUSION: The results correspond to those of clinical trials and support the efficacy and good tolerability of memantine in a realistic setting. Differences between the countries were observed regarding the baseline characteristics of patients (more female, older and more severe patients in Germany as well as less pretreatment with cholinesterase inhibitors) and regarding premature discontinuation and reported adverse drug reactions, which were both higher in Greece.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Antiparkinsonianos/uso terapêutico , Memantina/uso terapêutico , Atividades Cotidianas , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/psicologia , Antiparkinsonianos/efeitos adversos , Cognição/efeitos dos fármacos , Cognição/fisiologia , Feminino , Alemanha , Grécia , Humanos , Masculino , Memantina/efeitos adversos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Segurança do Paciente , Escalas de Graduação Psiquiátrica , Resultado do Tratamento
10.
Anticancer Res ; 26(2A): 1201-7, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16619525

RESUMO

BACKGROUND: Activating mutations of the FLT3 receptor tyrosine kinase are common in acute promyelocytic leukemia (APL) but have uncertain prognostic significance. Information regarding FLT3 expression levels in APL without FLT3 mutations is lacking. MATERIALS AND METHODS: Using RT-PCR, mutation analysis of the FLT3 gene, regarding internal tandem duplications (ITDs) and codon 835-836 point mutations, was performed and real-time PCR was carried out to determine the level of FLT3 expression in 11 APL patients at diagnosis and 5 in haematological remission with molecularly detectable disease. RESULTS: High levels of FLT3 transcript, at least a 10-fold increase compared to the normal controls, were found at diagnosis in all 3 mutated cases and in 2 patients without detectable FLT3 mutations. CONCLUSION: FLT3 overexpression can be documented in patients without FLT3 mutations. These patients might benefit from treatment using specific FLT3 tyrosine kinase inhibitors. Larger studies are needed to evaluate the clinical and biological significance of FLT3 overexpression in the absence of FLT3 mutations.


Assuntos
Leucemia Promielocítica Aguda/genética , Mutação Puntual , Tirosina Quinase 3 Semelhante a fms/genética , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Medula Óssea/metabolismo , Códon , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Proteínas de Fusão Oncogênica/biossíntese , Proteínas de Fusão Oncogênica/genética , Projetos Piloto , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Sequências de Repetição em Tandem , Tirosina Quinase 3 Semelhante a fms/biossíntese
11.
Behav Pharmacol ; 16(5-6): 499-510, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16148456

RESUMO

Newly developed cannabinoids may hold the promise of the development of useful and safe drugs. This study aimed to investigate the behavioral effects of the novel 1',1'-dithiolane delta8-HC analogue AMG-3, a cannabinomimetic molecule with high affinity for CB1/CB2 receptors. This analog was chosen for its binding affinity to these receptors, which is higher than that reported for delta8-tetrahydrocannabinol (delta8-THC). Behavioral responses were assessed after the administration of AMG-3 (1, 2, 4, 8 mg/kg, i.p.) in the open field, on the bar test, on the hot plate and in the intracranial self-stimulation procedure. AMG-3 increased the reactivity time on the hot plate in a dose- and time-dependent manner, indicating a long-lasting analgesic effect (at least 24 h). The substance was found dose-dependently to decrease spontaneous motor activity and to induce catalepsy, particularly at the highest dose (8 mg/kg). AMG-3 did not affect the rewarding value of intracranial self-stimulation, except to increase the reward threshold at the highest dose (8 mg/kg). The effects of the highest dose of AMG-3 on spontaneous activity and on the self-stimulation paradigm were completely reversed by pre-treatment with the CB1 receptor antagonist AM-251. These findings indicate that the administration of AMG-3 to rats elicits a specific behavioral profile, most probably associated with the activation of CB1 receptors and without effects indicating abuse potential.


Assuntos
Comportamento Animal/efeitos dos fármacos , Canabinoides/farmacologia , Animais , Comportamento Animal/fisiologia , Ligação Competitiva/efeitos dos fármacos , Canabinoides/química , Catalepsia/induzido quimicamente , Catalepsia/fisiopatologia , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Córtex Cerebral/efeitos dos fármacos , Córtex Cerebral/metabolismo , Cicloexanóis/metabolismo , Relação Dose-Resposta a Droga , Masculino , Estrutura Molecular , Atividade Motora/efeitos dos fármacos , Dor/fisiopatologia , Dor/prevenção & controle , Medição da Dor/métodos , Piperidinas/farmacologia , Pirazóis/farmacologia , Ratos , Ratos Sprague-Dawley , Receptor CB1 de Canabinoide/agonistas , Receptor CB1 de Canabinoide/antagonistas & inibidores , Receptor CB1 de Canabinoide/fisiologia , Fatores de Tempo , Trítio
12.
Ann Hematol ; 81(4): 182-6, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11976818

RESUMO

Amifostine (AMF) promotes in vitro growth and survival of hematopoietic progenitors. In this study we evaluated the efficacy of AMF in the treatment of anemia in patients with low-risk myelodysplastic syndromes (MDS) and the possible predicting value for response to AMF therapy of two types of in vitro clonogenic assays. Two different doses of AMF, 300 mg/m2 (group A, 11 patients) or 400 mg/m2 (group B, 16 patients), were studied. AMF was given three times weekly for 3 weeks, i.v., followed by 2 weeks off therapy. Patients were evaluated after two cycles of treatment. Partially or nonresponding patients of group A received 400 mg/m2 AMF and were reevaluated. An increase of hemoglobin (Hb) values of more than 2 g/dl and a 100% decrease in transfusion requirements for at least 6 weeks were defined as a complete response (CR) while an increase of Hb values of 1-2 g/dl or a 50% decrease in transfusion requirements was considered as a partial response (PR). In group A, two out of 11 (18.1%) patients achieved a CR with the initial dose and one of the nine that received 400 mg/m2 AMF achieved a PR. In group B, three out of 16 (18.7%) patients achieved a PR; the overall response rate in both groups was 22.2%. In group A, bone marrow progenitor assay was performed pre- and post-amifostine treatment. Erythroid burst-forming units (BFU-E) were increased in six out of 11 (54.5%) patients, and this increase preceded the rise in Hb levels in three of them. In group B, a clonogenic assay was performed in 11 out of 16 patients before AMF treatment. In vitro results after pretreatment with 500 microM amifostine confirmed the response of two MDS patients that achieved a PR. No response in vitro was observed in all eight nonresponding patients and in one PR patient. The lack of response in the clonogenic assays predicted for nonresponse to treatment with a predictive power of 91.8%. We conclude that 300 mg/m2 is an adequate initial treatment for low-risk MDS patients and both clonogenic assays have a strong predicting value for response to treatment.


Assuntos
Amifostina/administração & dosagem , Anemia Refratária/tratamento farmacológico , Síndromes Mielodisplásicas/complicações , Idoso , Idoso de 80 Anos ou mais , Anemia Refratária/etiologia , Células da Medula Óssea/efeitos dos fármacos , Ensaio de Unidades Formadoras de Colônias , Relação Dose-Resposta a Droga , Células Precursoras Eritroides/efeitos dos fármacos , Feminino , Hemoglobinas/análise , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/tratamento farmacológico , Valor Preditivo dos Testes , Prognóstico , Fatores de Risco
13.
Leuk Res ; 25(8): 665-71, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11397471

RESUMO

The efficacy and toxicity of amifostine (300 mg/m(2) three times a week for three consecutive weeks for a maximum of six courses) was evaluated in 12 patients with primary myelodysplastic syndromes. Dose escalation up to 400 mg/m(2) was allowed to patients who failed to respond. Hemoglobin concentration was increased > or = 1.5 g/dl in two (18%) of the 11 anemic patients. These two patients obtained transfusion independence for 20 weeks. Reticulocyte counts and ANC increased > or = 50% of baseline in four (44%) of the nine patients with reticulocytopenia and in three (25%) of the 12 neutropenic patients. Platelet count increased in three (50%) of the six patients with thrombocytopenia. Progenitor growth of CFU-GMs and BFU-Es improved in 8/12 patients. No major side effects were observed. In conclusion amifostine is well tolerated and can promote the growth of primitive hematopoietic progenitors and ameliorate the cytopenias in MDS patients.


Assuntos
Amifostina/uso terapêutico , Síndromes Mielodisplásicas/tratamento farmacológico , Idoso , Idoso de 80 Anos ou mais , Amifostina/efeitos adversos , Divisão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Esquema de Medicação , Feminino , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/sangue
14.
Curr Opin Ophthalmol ; 10(2): 121-5, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10537762

RESUMO

Leaking blebs may be encountered in the early postoperative period, or months to years after filtering surgery. Early postoperative bleb leaks are most often related to surgical trauma to the conjunctiva and can be avoided by careful surgical technique. Spontaneous late bleb leaks occur more frequently in glaucoma filtering surgery following adjunctive use of antimetabolites and full-thickness procedures. As we endeavor to achieve better long-term success with filtering surgery, antimetabolites have gained increasing popularity. With this change in clinical practice, a higher rate of bleb leaks is being recognized. These leaks may be uncomplicated or may be associated with sight-threatening complications such as endophthalmitis. The plethora of treatment options for bleb leaks described in the literature reflects the widespread nature of this problem. It also reflects the failure of any one particular approach not only to resolve bleb leaks but also to prevent their recurrence. This paper reviews the contemporary surgical management of leaking blebs and formulates a practical approach to their management.


Assuntos
Cirurgia Filtrante/efeitos adversos , Complicações Pós-Operatórias/cirurgia , Antimetabólitos/administração & dosagem , Glaucoma/cirurgia , Humanos , Soluções Oftálmicas , Complicações Pós-Operatórias/tratamento farmacológico , Reoperação , Prevenção Secundária
15.
IEEE Trans Neural Netw ; 8(5): 1026-30, 1997.
Artigo em Inglês | MEDLINE | ID: mdl-18255705

RESUMO

The focus of this paper is a convergence study of the frequency sensitive competitive learning (FSCL) algorithm. We approximate the final phase of FSCL learning by a diffusion process described by the Fokker-Plank equation. Sufficient and necessary conditions are presented for the convergence of the diffusion process to a local equilibrium. The analysis parallels that by Ritter-Schulten (1988) for Kohonen's self-organizing map. We show that the convergence conditions involve only the learning rate and that they are the same as the conditions for weak convergence described previously. Our analysis thus broadens the class of algorithms that have been shown to have these types of convergence characteristics.

16.
IEEE Trans Neural Netw ; 7(3): 752-6, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-18263470

RESUMO

We study the codeword distribution for a conscience-type competitive learning algorithm, frequency sensitive competitive learning (FSCL), using one-dimensional input data. We prove that the asymptotic codeword density in the limit of large number of codewords is given by a power law of the form Q(x)=C.P(x)(alpha), where P(x) is the input data density and alpha depends on the algorithm and the form of the distortion measure to be minimized. We further show that the algorithm can be adjusted to minimize any L(p) distortion measure with p ranging in (0,2].

17.
Ophthalmic Plast Reconstr Surg ; 11(4): 278-80, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8746820

RESUMO

Progressive hemifacial atrophy or Parry Romberg syndrome may present with variable ocular features, the commonest being enophthalmos. We report a mild case in a 62-year-old man who presented with upper eyelid retraction, nocturnal lagophthalmos, and symptoms of corneal exposure. Recession of the levator muscle corrected the lid retraction and abolished the symptoms of corneal exposure.


Assuntos
Doenças Palpebrais/etiologia , Hemiatrofia Facial/complicações , Doenças da Córnea/etiologia , Doenças Palpebrais/cirurgia , Pálpebras/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Músculos Oculomotores/cirurgia
18.
Aust N Z J Ophthalmol ; 22(3): 167-73, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7818874

RESUMO

Necrotising anterior scleritis is a rare sequela of ocular surgery. Typically an intense scleral inflammation develops at or adjacent to the site of the previous surgery. Necrosis supervenes and may then progress circumferentially to involve much of the anterior sclera. Surgically induced necrotising scleritis (SINS) has been previously described after cataract extraction, trabeculectomy, retinal detachment and strabismus surgery. We report three cases of SINS following pterygium excision. In each case the disease was prolonged, progressive and required protracted immunosuppressive therapy.


Assuntos
Segmento Anterior do Olho/patologia , Complicações Pós-Operatórias/patologia , Pterígio/cirurgia , Esclerite/etiologia , Idoso , Segmento Anterior do Olho/efeitos dos fármacos , Humanos , Imunossupressores/uso terapêutico , Masculino , Pessoa de Meia-Idade , Necrose , Esclerite/tratamento farmacológico , Esclerite/patologia
19.
Anticancer Res ; 12(6B): 2177-80, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1295465

RESUMO

Point mutations of the ras genes have been detected in various hematologic malignancies. This genetic event may either occur in all malignant cells or be acquired by different subclones, which however, cannot be demonstrated adequately by analyzing only DNA derived from patient specimens. The availability of the ras p21 monoclonal antibody (MoAb) Y 13259 makes possible the direct study of the distribution of the ras gene product in human malignant cells. In this report the expression of the ras p21 oncoprotein in the bone marrow smears of 35 children with acute leukemia has been analyzed. The smears were treated with the MoAb Y 13259, biotinylated goat anti-rat IgG, streptavidin, peroxidase and stained with diaminobenzidine (DAB). The intensity of the staining was evaluated by two independent observers as negative or equivocal (-/+), moderate (+) or intense (++), by counting one thousand cells. Patients were also classified according to the percentage of the stained cells into four groups (0, I, II, III). It was found that 22/35 (63%) were (+) or (++) positive as follows: 11/21 (52%) with ALL CALLA (+), 2/2 ALL-B, 3/3 ALL-T and 6/9 AML. In Group 0 (none of the blasts was stained) were 13/35 (37%), as well as in Group I (1 to 25% of the blasts stained 1+ or 2+ positive), while in Group II (26 to 50% positive stained) 3/35 and in Group III (more than 51% stained) 6/35, all of which were AML (6/9). It is concluded that the immunohistochemical analysis of the ras p21 in blast cells of children with acute leukemia may demonstrate that ras gene expression in some subclones, the intensity and percentage of which may be of some clinical importance.


Assuntos
Medula Óssea/patologia , Leucemia/genética , Leucemia/patologia , Proteínas Proto-Oncogênicas p21(ras)/análise , Doença Aguda , Crise Blástica/patologia , Linfoma de Burkitt/genética , Linfoma de Burkitt/patologia , Criança , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/patologia , Leucemia-Linfoma de Células T do Adulto/genética , Leucemia-Linfoma de Células T do Adulto/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras B/genética , Leucemia-Linfoma Linfoblástico de Células Precursoras B/patologia
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