Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 31
Filtrar
1.
Bone Marrow Transplant ; 51(5): 680-6, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26752147

RESUMO

Adverse reactions (ARs) during the infusion of cellular therapy products (CTPs) are common in patients undergoing hematopoietic stem cell transplantation (HSCT). We retrospectively studied pediatric patients undergoing autologous and allogeneic HSCT to determine the incidence and grade of ARs during stem cell infusion and their predictors. We analyzed data from 213 patients (120 allogeneic and 93 autologous) who received at least 1 CTP, totaling 361 infusion episodes. Serious ARs, defined as grade 2 and 3, occurred in 25 and 11% of infusions, respectively. No grade 4 or 5 ARs were noted. Independent risk factors for developing a serious AR included stem cell source (PBSC vs marrow (odds ratio (OR) 1.8, 95% confidence interval (CI): 0.4-9); cord vs marrow (OR 7.3, 95% CI: 1.3-40), overall P=0.0001) but manipulated CTPs were protective (OR 0.4, 95% CI: 0.2-0.7, P=0.004). Unlike previous adult studies, WBC and granulocyte content were not found to be risk factors in this pediatric population. These data suggest that children tolerate higher WBC content during infusion of CTPs and support the use of manipulated CTP, as indicated, to reduce the risk of adverse infusion reactions.


Assuntos
Transplante de Células-Tronco/efeitos adversos , Criança , Pré-Escolar , Feminino , Granulócitos , Humanos , Leucócitos , Masculino , Estudos Retrospectivos , Fatores de Risco , Transplante de Células-Tronco/estatística & dados numéricos , Células-Tronco/citologia , Transplante Autólogo , Transplante Homólogo
2.
Vet Parasitol ; 210(1-2): 64-8, 2015 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-25801226

RESUMO

A clinical field investigation was conducted to evaluate the safety and efficacy of 10% imidacloprid/2.5% moxidectin for the treatment of ear mites (Otodectes cynotis) in dogs. The study was a multi-centered, blinded, positive controlled, randomized clinical trial conducted under field conditions with privately owned pets. A total of 17 veterinary clinics enrolled cases for the study. An otoscopic examination was performed to confirm the presence of O. cynotis residing in the ear of the dog prior to enrollment. A single-dog household was enrolled in the study if the dog had 5 or more ear mites and an acceptable physical examination. A multi-dog household was eligible if at least one dog in the household had 5 or more mites and all dogs in the household had acceptable physical exams and met the inclusion criteria. Qualified households were randomly assigned to treatments to receive either 10% imidacloprid+2.5% moxidectin topical solution or topical selamectin solution (positive control product) according to a pre-designated enrollment ratio of 2:1, respectively. If more than one dog in a multiple dog household had adequate numbers of ear mites, one dog was randomly selected to represent the household for efficacy evaluation prior to treatment. Treatments were administered twice per label and dose banding directions for each product approximately 28 days apart (Days 0 and 28), by the dog's owner at the study site. All dogs in a household were treated on the same day and with the same product. The owners completed a post-treatment observation form one day after each treatment. Post-treatment otoscopic examinations were performed by the investigators or attending veterinarian on Days 28 and 56. Physical examinations were performed on Days 0 and 56. One hundred and four (104) households were evaluated for efficacy on SD 28, and 102 households were evaluated for efficacy on SD 56. The dogs' ages ranged from 2 months to 16 years. A total of 247 dogs were evaluated for safety. Percent efficacy was based on the percentage of dogs cleared of ear mites. Mite clearance on Day 28 was 71% for the imidacloprid+moxidectin group and 69% for the selamectin group. Mite clearance on Day 56 was 82% for the imidacloprid+moxidectin group and 74% for the selamectin group. No serious adverse events associated with either product were observed during the study. The study demonstrated that 10% imidacloprid+2.5% moxidectin applied using two topical treatments, 28 days apart, was safe and achieved similar efficacy against O. cynotis as selamectin treatments applied and evaluated under the same conditions.


Assuntos
Doenças do Cão/parasitologia , Otopatias/veterinária , Imidazóis/uso terapêutico , Macrolídeos/uso terapêutico , Infestações por Ácaros/veterinária , Nitrocompostos/uso terapêutico , Animais , Doenças do Cão/tratamento farmacológico , Cães , Combinação de Medicamentos , Otopatias/parasitologia , Imidazóis/administração & dosagem , Inseticidas/administração & dosagem , Inseticidas/uso terapêutico , Ivermectina/análogos & derivados , Ivermectina/uso terapêutico , Macrolídeos/administração & dosagem , Neonicotinoides , Nitrocompostos/administração & dosagem
3.
Neurogastroenterol Motil ; 16(2): 223-31, 2004 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15086876

RESUMO

We investigated the effects of the selective NK(3) tachykinin receptor antagonist, SB-235375, on noxious signalling from gut and skin and on intestinal motility in anaesthetized rats. We also measured penetrance into brain and spinal cord. Nociceptive responses in reaction to colorectal distension and skin pinch were assessed by recording the electromyogram (EMG) from the external oblique muscle (a visceromotor response). Motility was measured by recording intraluminal pressure waves during changes in baseline pressure in the jejunum. Colorectal compliance was assessed by measuring luminal pressure change during isovolumic distension. SB-235375 (20 mg kg(-1), by i.v. bolus) reduced the EMG response to colorectal distension by over 90%. The reduction was slow at onset, peaked at about 60 min, and lasted for over 2 h. Responses to noxious skin pinch were unchanged. Amplitudes of propulsive waves in the jejunum were slightly reduced, but their frequency of occurrence was unchanged. SB-235375 decreased colorectal compliance by 5-10%. There was undetectable penetration of i.v. SB-235375 into brain or spinal cord. We conclude that SB-235375 acts peripherally to substantially reduce nociceptive signalling from colorectum without affecting noxious signalling from skin and with little effect on intestinal motility.


Assuntos
Acetatos/farmacologia , Motilidade Gastrointestinal/efeitos dos fármacos , Intestinos/fisiologia , Dor/fisiopatologia , Quinolinas/farmacologia , Receptores da Neurocinina-3/antagonistas & inibidores , Acetatos/análise , Acetatos/farmacocinética , Anestesia , Animais , Barreira Hematoencefálica/fisiologia , Eletromiografia , Sistema Nervoso Entérico/fisiologia , Intestinos/efeitos dos fármacos , Masculino , Nociceptores/efeitos dos fármacos , Nociceptores/fisiologia , Quinolinas/análise , Quinolinas/farmacocinética , Ratos , Ratos Sprague-Dawley , Pele/inervação
4.
Brain Res ; 124(2): 283-303, 1977 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-191150

RESUMO

Experiments were carried out in rats to (1) elaborate upon the sepcificity of drug action in the periaqueductal gray matter (PAG), and (2) to evaluate the posible congruence of PAG sites of morphine-induced and stimulation-produced analgesis (SPA) applied at virtually identical PAG loci. It was demonstrated that the effect of morphine intracerebrally (i,c.) administered into the PAG was not duplicated by other centrally acting agents (chlorpromazine, chlordiazepoxide, pentobarbital or naloxone) administered i.c. at the same PAG site. This selective action of morphine in the PAG was further demonstrated not to be test-bound since morphine significantly altered responding in all four of the analgesiometric tests employed. Thus, multiple i.c. injections of drugs at the same PAG locus were useful in demonstrating site specificity of drug action where behavioral and electroencephalographic methods alone had previously provided ambiguous information. Morphine-induced analgesia and SPA, evaluated at virtually coincident PAG sites, revealed only a general congruence of efficacious loci. The most effective PAG loci for morphine-induced analgesia were not the same as those for SPA; analgesia effected by one analgesia-producing manipulation did not reliably predict that analgesia would also be produced by the other analgesia-producing manipulation at the PAG sites examined. In general, the more efficacious analgesia-producing PAG loci were localized in the ventral-ventrolateral PAG.


Assuntos
Analgesia , Aqueduto do Mesencéfalo/efeitos dos fármacos , Morfina/farmacologia , Receptores Opioides/análise , Animais , Clordiazepóxido/farmacologia , Clorpromazina/farmacologia , Relação Dose-Resposta a Droga , Masculino , Naloxona/farmacologia , Pentobarbital/farmacologia , Ratos
5.
Eur J Pharmacol ; 357(2-3): 115-20, 1998 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-9797026

RESUMO

5-HT4 receptors are concentrated in areas of the brain which are rich in dopamine neuronal markers, which may suggest that they influence motor and reward processes. We tested this hypothesis by examining the effects of a 5-HT4 receptor antagonist, 8-amino-7-chloro-(N-butyl-4-piperidyl)methylbenzo-1,4-dioxan-5-car boxylate hydrochloride (SB-204070-A) on amphetamine- and nicotine-induced locomotor stimulation in intact rats. In rats with unilateral 6-hydroxydopamine-induced lesions of the ascending nigrostriatal dopaminergic projection, SB-204070-A was tested for its effects on amphetamine-induced rotation. SB-204070-A was also tested for its effects on rewarded behaviour maintained by intracranial self-stimulation. SB-204070-A did not alter behaviour under any of these conditions, suggesting a lack of involvement of the 5-HT4 receptor in motor and reward processes.


Assuntos
Comportamento Animal/efeitos dos fármacos , Dioxanos/farmacologia , Atividade Motora/efeitos dos fármacos , Piperidinas/farmacologia , Antagonistas da Serotonina/farmacologia , Anfetamina/farmacologia , Animais , Cocaína/farmacologia , Hipercinese/induzido quimicamente , Masculino , Nicotina/farmacologia , Ratos , Ratos Sprague-Dawley , Autoestimulação/efeitos dos fármacos
6.
Eur J Pharmacol ; 401(3): 419-28, 2000 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-10936502

RESUMO

For progression to clinical trials in stroke, putative neuroprotective compounds should show robust efficacy post-ischaemia in several experimental models of stroke. This paper describes the characterisation of (+)(1S, 2R)-cis-1-[4-(1-methyl-1-phenylethyl)phenoxy]-2-methylamino indane hydrochloride (SB-221420-A), a Ca(2+) and Na(+) channel antagonist. SB-221420-A inhibited (IC(50)=2.2 microM) N-type voltage-operated Ca(2+) channel currents in cultured superior cervical ganglion neurons, which were pretreated with 10 microM nimodipine to block L-type voltage-operated Ca(2+) channel currents. In dorsal root ganglion neurons pretreated with 1 microM omega-conotoxin GVIA to block N-type voltage-operated Ca(2+) channel currents, SB-221420-A inhibited the residual Ca(2+) current with an IC(50) of 7 microM. SB-221420-A also inhibited Na(+) currents in dorsal root ganglion neurons with an IC(50) of 8 microM. In rats, the pharmacokinetic profile of SB-221420-A shows that it has a half-life of 6.4 h, a high volume of distribution, is highly brain penetrating, and has no persistent metabolites. Following bilateral carotid artery occlusion in gerbils, SB-221420-A significantly reduced the level of ischaemia-induced hyperlocomotor activity and the extent of hippocampal CA1 cell loss compared to the ischaemic vehicle-treated group. SB-221420-A was also effective in focal models of ischaemia. In the mouse permanent middle cerebral artery occlusion model, SB-221420-A (10 mg/kg) administered intravenously, post-ischaemia significantly (P<0.05) reduced lesion volume compared to the ischaemic vehicle-treated group. In the normotensive rat permanent middle cerebral artery occlusion model, SB-221420-A (10 mg/kg) administered intravenously over 1 h, beginning 30 min postmiddle cerebral artery occlusion, significantly (P<0.05) reduced lesion volume from 291+/-16 to 153+/-30 mm(3), compared to ischaemic vehicle-treated controls when measured 24 h postmiddle cerebral artery occlusion. Efficacy was maintained when the same total dose of SB-221420-A was infused over a 6-h period, beginning 30 min postmiddle cerebral artery occlusion. SB-221420-A also significantly (P<0.05) reduced lesion volume following transient middle cerebral artery occlusion in normotensive rats and permanent middle cerebral artery occlusion in spontaneously hypertensive rats (SHR). Investigation of the side effect profile using the Irwin screen in mice revealed that, at neuroprotective doses, there were no overt behavioural or cardiovascular changes. These data demonstrate that robust neuroprotection can be seen post-ischaemia with SB-221420-A in both global and focal ischaemia with no adverse effects at neuroprotective doses, and indicate the potential utility of a mixed cation blocker to improve outcome in cerebral ischaemia.


Assuntos
Bloqueadores dos Canais de Cálcio/farmacologia , Indanos/farmacologia , Fármacos Neuroprotetores/farmacologia , Bloqueadores dos Canais de Sódio , Acidente Vascular Cerebral/prevenção & controle , Anestesia , Animais , Animais Recém-Nascidos , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Estenose das Carótidas/fisiopatologia , Estenose das Carótidas/prevenção & controle , Células Cultivadas , Estado de Consciência , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos , Gerbillinae , Hemodinâmica/efeitos dos fármacos , Hipertensão/fisiopatologia , Indanos/farmacocinética , Infarto da Artéria Cerebral Média/patologia , Infarto da Artéria Cerebral Média/prevenção & controle , Ataque Isquêmico Transitório/fisiopatologia , Ataque Isquêmico Transitório/prevenção & controle , Masculino , Potenciais da Membrana/efeitos dos fármacos , Taxa de Depuração Metabólica , Camundongos , Atividade Motora/efeitos dos fármacos , Neurônios Aferentes/citologia , Neurônios Aferentes/efeitos dos fármacos , Neurônios Aferentes/fisiologia , Ratos , Ratos Endogâmicos SHR , Ratos Sprague-Dawley , Acidente Vascular Cerebral/fisiopatologia , Distribuição Tecidual
7.
Leukemia ; 28(3): 658-65, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23989431

RESUMO

The efficacy of reduced intensity conditioning (RIC) allogeneic hematopoietic cell transplantation (HCT) for Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) is uncertain. We analyzed 197 adults with Ph+ ALL in first complete remission; 67 patients receiving RIC were matched with 130 receiving myeloablative conditioning (MAC) for age, donor type and HCT year. Over 75% received pre-HCT tyrosine kinase inhibitors (TKIs), mostly imatinib; 39% (RIC) and 49% (MAC) were minimal residual disease (MRD)(neg) pre-HCT. At a median 4.5 years follow-up, 1-year transplant-related mortality (TRM) was lower in RIC (13%) than MAC (36%; P=0.001) while the 3-year relapse rate was 49% in RIC and 28% in MAC (P=0.058). Overall survival (OS) was similar (RIC 39% (95% confidence interval (CI) 27-52) vs 35% (95% CI 27-44); P=0.62). Patients MRD(pos) pre-HCT had higher risk of relapse with RIC vs MAC (hazard ratio (HR) 1.97; P=0.026). However, patients receiving pre-HCT TKI in combination with MRD negativity pre-RIC HCT had superior OS (55%) compared with a similar MRD population after MAC (33%; P=0.0042). In multivariate analysis, RIC lowered TRM (HR 0.6; P=0.057), but absence of pre-HCT TKI (HR 1.88; P=0.018), RIC (HR 1.891; P=0.054) and pre-HCT MRD(pos) (HR 1.6; P=0.070) increased relapse risk. RIC is a valid alternative strategy for Ph+ ALL patients ineligible for MAC and MRD(neg) status is preferred pre-HCT.


Assuntos
Transplante de Medula Óssea , Neoplasia Residual , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Proteínas Tirosina Quinases/antagonistas & inibidores , Indução de Remissão , Taxa de Sobrevida , Condicionamento Pré-Transplante , Adulto , Animais , Feminino , Cobaias , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Transplante Homólogo , Adulto Jovem
8.
Bone Marrow Transplant ; 48(8): 1056-64, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23419433

RESUMO

Although the role of autologous hematopoietic cell transplantation (auto-HCT) is well established in neuroblastoma (NBL), the role of allogeneic HCT (allo-HCT) is controversial. The Center for International Blood and Marrow Transplant Research conducted a retrospective review of 143 allo-HCT for NBL reported in 1990-2007. Patients were categorized into two different groups: those who had not (Group 1) and had (Group 2) undergone a prior auto-HCT (n=46 and 97, respectively). One-year and five-year OS were 59% and 29% for Group 1 and 50% and 7% for Group 2, respectively. Among donor types, disease-free survival (DFS) and OS were significantly lower for unrelated transplants at 1 and 3 years but not at 5 years post HCT. Patients in CR or very good partial response (VGPR) at transplant had lower relapse rates and better DFS and OS, compared with those not in CR or VGPR. Our analysis indicates that allo-HCT can cure some neuroblastoma patients, with lower relapse rates and improved survival in patients without a history of prior auto-HCT as compared with those patients who had previously undergone auto-HCT. Although the data do not address why either strategy was chosen for patients, allo-HCT after a prior auto-HCT appears to offer minimal benefit. Disease recurrence remains the most common cause of treatment failure.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Neuroblastoma/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Coleta de Dados , Intervalo Livre de Doença , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Humanos , Lactente , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de Sobrevida , Transplante Autólogo , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
9.
Bone Marrow Transplant ; 47(3): 395-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21552303

RESUMO

Hodgkin lymphoma (HL) is cured in the majority of children and adolescents. However, there remains a group of patients with primary refractory or relapsed disease for whom cure is more difficult to achieve. Most of these patients receive high-dose chemotherapy followed by auto-SCT, with expected cure rates ranging from 40 to 60%. Conditioning regimens often consist of multiple non-cross-resistant agents, with well-described risks of morbidity and mortality. The use of single-agent high-dose melphalan (HDM) as conditioning, before autologous rescue, has been described in adult patients at our center, with comparable efficacy and less morbidity. We present a series of eight pediatric patients conditioned with single-agent HDM before autologous stem cell rescue for relapsed and primary refractory HL. All patients engrafted with a median of 12 days to neutrophil engraftment. Two patients subsequently relapsed. Seven patients are currently alive, and seven of eight patients have no evidence of disease (one in CR3). Toxicities included grade 4 hematologic in 8/8, grade 3 mucositis in 3/8, grade 3 infectious in 2/8 and grade 4 infectious in 1/8. Our analysis suggests that this regimen is feasible in pediatric patients with acceptable engraftment and toxicity.


Assuntos
Doença de Hodgkin/tratamento farmacológico , Doença de Hodgkin/terapia , Melfalan/administração & dosagem , Agonistas Mieloablativos/administração & dosagem , Transplante de Células-Tronco/métodos , Adolescente , Canadá , Criança , Resistencia a Medicamentos Antineoplásicos , Feminino , Humanos , Linfoma/terapia , Masculino , Melfalan/farmacologia , Agonistas Mieloablativos/farmacologia , Recidiva , Estudos Retrospectivos , Condicionamento Pré-Transplante/métodos
10.
Bone Marrow Transplant ; 47(2): 203-11, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21441963

RESUMO

Although reduced-intensity conditioning (RIC) and non-myeloablative (NMA)-conditioning regimens have been used for over a decade, their relative efficacy vs myeloablative (MA) approaches to allogeneic hematopoietic cell transplantation in patients with AML and myelodysplasia (MDS) is unknown. We compared disease status, donor, graft and recipient characteristics with outcomes of 3731 MA with 1448 RIC/NMA procedures performed at 217 centers between 1997 and 2004. The 5-year univariate probabilities and multivariate relative risk outcomes of relapse, TRM, disease-free survival (DFS) and OS are reported. Adjusted OS at 5 years was 34, 33 and 26% for MA, RIC and NMA transplants, respectively. NMA conditioning resulted in inferior DFS and OS, but there was no difference in DFS and OS between RIC and MA regimens. Late TRM negates early decreases in toxicity with RIC and NMA regimens. Our data suggest that higher regimen intensity may contribute to optimal survival in patients with AML/MDS, suggesting roles for both regimen intensity and graft vs leukemia in these diseases. Prospective studies comparing regimens are needed to confirm this finding and determine the optimal approach to patients who are eligible for either MA or RIC/NMA conditioning.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia Mieloide Aguda/terapia , Síndromes Mielodisplásicas/terapia , Condicionamento Pré-Transplante/métodos , Adolescente , Adulto , Idoso , Intervalo Livre de Doença , Feminino , Humanos , Leucemia Mieloide Aguda/cirurgia , Masculino , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/cirurgia , Transplante Homólogo , Resultado do Tratamento , Adulto Jovem
14.
Leukemia ; 22(2): 281-6, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18033318

RESUMO

In children with acute lymphoblastic leukemia (ALL) with isolated central nervous system (CNS) relapse and a human leucocyte antigen (HLA)-matched sibling, the optimal treatment after attaining second remission is unknown. We compared outcomes in 149 patients enrolled on chemotherapy trials and 60 HLA-matched sibling transplants, treated in 1990-2000. All patients achieved a second complete remission. Groups were similar, except the chemotherapy recipients were younger at diagnosis, less likely to have T-cell ALL and had longer duration (> or = 18 months) first remission. To adjust for time-to-transplant bias, left-truncated Cox's regression models were constructed. Relapse rates were similar after chemotherapy and transplantation. In both treatment groups, relapse rates were higher in older children (11-17 years; RR 2.81, P=0.002) and shorter first remission (< 18 months; RR 3.89, P<0.001). Treatment-related mortality rates were higher after transplantation (RR 4.28, P=0.001). The 8-year probabilities of leukemia-free survival adjusted for age and duration of first remission were similar after chemotherapy with irradiation and transplantation (66 and 58%, respectively). In the absence of an advantage for one treatment option over another, the data support use of either intensive chemotherapy with irradiation or HLA-matched sibling transplantation with total body irradiation containing conditioning regimen for children with ALL in second remission after an isolated CNS relapse.


Assuntos
Antineoplásicos/uso terapêutico , Transplante de Medula Óssea/métodos , Neoplasias do Sistema Nervoso Central/terapia , Histocompatibilidade , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Adolescente , Neoplasias do Sistema Nervoso Central/etiologia , Criança , Pré-Escolar , Coleta de Dados , Intervalo Livre de Doença , Feminino , Antígenos HLA , Humanos , Infiltração Leucêmica/etiologia , Infiltração Leucêmica/terapia , Estudos Longitudinais , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Radioterapia/métodos , Recidiva , Indução de Remissão , Irmãos , Condicionamento Pré-Transplante/métodos , Resultado do Tratamento
15.
J Appl Physiol ; 40(2): 278-80, 1976 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-942949

RESUMO

An electrolytic approach to cutting small-diameter stainless steel tubing is described. The method is superior to abrasion or manual methods because it produces a clear lumen in the smallest diameter tubing available. The method is simple, quick, and inexpensive and has been found valuable for making small injection needles, small tissue punches, and for repairing broken or occluded microliter syringes.


Assuntos
Eletrólise , Injeções/instrumentação , Aço Inoxidável , Animais , Cateterismo/instrumentação , Cães , Seringas
16.
Perception ; 11(6): 691-701, 1982.
Artigo em Inglês | MEDLINE | ID: mdl-6225990

RESUMO

Two experiments are reported with young Down's syndrome and normal children matched for mental age, sex, and social class. In one, Down's syndrome children performed at chance level on two tactual--visual cross-modal tasks, and only the oldest succeeded with one of two visual--visual within-modal tasks. The modal children performed at above chance level on the visual--visual tasks, and on the tactual--visual tasks the oldest succeeded on two and the youngest on one of the tasks. These results suggest that Down's syndrome children may have some sort of difficulty involving tactual perception. The second experiment examined the effect of touch on visual behaviour. Down's syndrome children and their matched controls looked at pairs of shapes which sometimes could be touched and sometimes could not. In the former condition the Down's syndrome children touched less, and looking and touching was less coordinated than that of normal children. However, both groups made fewer but longer looks when they could touch the shapes. In the light of these results the role of tactual perception in Down's syndrome children is discussed.


Assuntos
Síndrome de Down/psicologia , Tato , Percepção Visual , Fatores Etários , Atenção , Desenvolvimento Infantil , Pré-Escolar , Humanos , Lactente , Psicologia da Criança , Desempenho Psicomotor
17.
Nature ; 324(6095): 372-5, 1986.
Artigo em Inglês | MEDLINE | ID: mdl-3024012

RESUMO

Macrophages, granulocytes and many lymphocytes express or secrete receptors for the Fc domain of immunoglobulins (Ig). These Fc receptors (FcRs) are heterogeneous and can be distinguished on the basis of their cellular distribution and specificities for different immunoglobulin isotypes. Although their functions are not completely understood, FcRs are known to be involved in triggering various effector cell functions and in regulating differentiation and development of B-cells. One of the best characterized is the mouse macrophage-lymphocyte receptor for IgG1 and IgG2b (ref. 5). On macrophages, this FcR mediates the endocytosis of antibody-antigen complexes via coated pits and coated vesicles, the phagocytosis of Ig-coated particles, and the release of various inflammatory and cytotoxic agents. It is possible that the receptor possesses an intrinsic ligand-activated ion channel activity responsible for some of these functions. The IgG1/IgG2b FcR has been isolated and shown to be a transmembrane glycoprotein of relative molecular mass (Mr) 47,000-60,000 (47-60 K) containing four N-linked oligosaccharide chains and a large (greater than 10K) cytoplasmic domain. It is also immunologically indistinguishable from the murine Ly-17 alloantigen which, in turn, is tightly linked to the Mls lymphocyte activation locus. Here we describe the isolation and characterisation of a complementary DNA clone encoding the whole of the IgG1/IgG2b FcR expressed by the mouse macrophage-like cell line P388D1. The receptor is a member of the immunoglobulin superfamily and, like Ly-17, maps to the distal portion of chromosome 1. cDNA probes detect one or two mRNA species in FcR+ macrophage and B-cell lines, but not in FcR- cells or a receptor-deficient variant derived from a FcR+ B-cell line. Finally, DNA hybridization analysis indicates the receptor gene is partially deleted or rearranged in the FcR- variant.


Assuntos
Clonagem Molecular , DNA/metabolismo , Linfócitos/imunologia , Macrófagos/imunologia , Receptores Fc/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Linhagem Celular , Enzimas de Restrição do DNA , Camundongos , RNA Mensageiro/genética
18.
J Child Lang ; 24(1): 57-79, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9154009

RESUMO

Investigation of children's understanding of the cognitive verb forget has shown that young children do not consider the role of prior knowledge when using this verb. Thus, someone may be said to have forgotten a fact despite not ever having previously known it. However, forget can also be used to refer to a failure to recall a prior intention. Three experiments examined the role of prior intention as well as prior knowledge in the comprehension of forget by 160 young children aged four to eight years. The results showed that children initially have two interpretations of forget: as an unfulfilled desire rather than a failure to recall a prior intention, and as a state of not knowing rather than a failure to recall prior knowledge. Explanations for the late comprehension of forget are discussed in terms of representation of knowledge and intention, processing capacity and exposure to pragmatic usages.


Assuntos
Cognição , Aprendizagem Verbal , Vocabulário , Fatores Etários , Criança , Pré-Escolar , Humanos
19.
J Child Lang ; 26(3): 699-720, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10603701

RESUMO

Children's narratives consist of event clauses and contextualizing or 'evaluative' clauses. Bamberg & Damrad-Frye (1991) and Bamberg (1994) claimed that young children make limited use of evaluative clauses because they are less able to adopt a global perspective on the narrative. In an earlier study, Karmiloff-Smith (1985) demonstrated that the narratives of younger children have coherence only at a local level. However, Wellman & Bartsch (1988) showed that young children could produce evaluative-like causal explanations if given a specific prompt. The present study on 160 young children aged five, seven, nine and eleven years examined their production of evaluatives in narratives of a story presented as a video sequence with no spoken dialogue, to ensure that the children's production was not simply a re-working of verbal input. Results indicated that prompts greatly facilitated children's production of evaluatives and that they could adopt a global perspective on the story when formulating evaluatives. These results indicate that limitations in the narratives of young children are more plausibly explained by contextual factors influencing language production and by constraints on working memory than by children's presumed lack of understanding of the structure of events or their inferences about the minds of the characters.


Assuntos
Linguagem Infantil , Idioma , Fala , Comportamento Verbal , Gravação em Vídeo , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Distribuição Aleatória
20.
Genet Res ; 56(2-3): 193-201, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2272510

RESUMO

Transmission ratio distortion (TRD) is a property of the complete t-haplotype which results in the preferential transmission of the t-haplotype chromosome from heterozygous t/+ males to the majority of the progeny. Available data suggest that in t/+ males, a dysfunction of the wild-type sperm within the female reproductive tract is responsible for the observed deviation from Mendelian segregation ratios. Genetically, Lyon has shown that multiple loci within the t-complex are required for maximum levels of TRD. These loci include multiple t-complex distorters (Tcds) which act upon a single t-complex responder (Tcr). Testis-expressed genes have been cloned which map to the same subregions of the t-complex as the Tcds and Tcr and are thus considered candidate genes for the products of these loci. To begin to understand how the products of these loci biochemically control TRD, the expression of three TRD-candidate genes (Tcp-1, D17Leh117c3, and D17Leh66) has been determined in populations of spermatocytes and differentiated spermatids purified to near homogeneity by unit gravity sedimentation. Fractions covering the entire gradient were analysed resulting in a more accurate picture of the precise timing of expression than previously reported. Transcription of all three genes was up-regulated in pachytene primary spermatocytes and persisted at stable levels through the haploid spermatid stages. Significantly, only levels of mRNA encoded by D17Leh66, the candidate gene for Tcr, increased from early round to elongating-stage spermatids. If this pattern of expression does, in fact, represent Tcr, these data provide the first direct evidence that wild-type and t-haplotype Tcr elements could be differentially expressed in haploid spermatids.


Assuntos
Regulação da Expressão Gênica , Peptídeos e Proteínas de Sinalização Intracelular , Proteínas Associadas aos Microtúbulos , Proteínas Nucleares/genética , Espermatozoides/metabolismo , Hormônios Testiculares/genética , Animais , Células Cultivadas , Masculino , Camundongos , Espermátides/metabolismo , Espermatócitos/metabolismo , Espermatozoides/citologia , Ubiquitina-Proteína Ligases , Região do Complexo-t do Genoma
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa