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1.
Cochrane Database Syst Rev ; 8: CD014890, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37531583

RESUMO

BACKGROUND: Second language (L2) learners are a heterogeneous group. Their L2 skills are highly varied due to internal factors (e.g. cognitive development) and external factors (e.g. cultural and linguistic contexts). As a group, their L2 vocabulary skills appear to be lower than their monolingual peers. This pattern tends to persist over time and may have negative consequences for social interaction and inclusion, learning, and academic achievement. OBJECTIVES: To examine the immediate and long-term effects of second language (L2) vocabulary interventions targeting L2 learners up to six years of age on vocabulary and social-emotional well-being. To examine the associations between L2 vocabulary interventions and the general characteristics of L2 learners (e.g. age, L2 exposure, and L1 skills). SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was December 2022. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing the effects of vocabulary interventions for L2 learners up to six years of age with standard care. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our primary outcomes were 1. receptive and 2. expressive L2 vocabulary (both proximal and distal), and 3. mean length of utterance (MLU; which is a measure of potential adverse effects). Our secondary outcomes were 4. L2 narrative skills, 5. L1 receptive vocabulary (both proximal and distal), 6. L1 expressive vocabulary (both proximal and distal), 7. L1 listening comprehension, 8. L2 grammatical knowledge, 9. L2 reading comprehension (long-term), and 10. socio-emotional well-being (measured with Strengths and Difficulties Questionnaire). MAIN RESULTS: We found 12 studies involving 1943 participants. Two studies were conducted in Norway, seven in the USA, and single studies conducted in Canada, China, and the Netherlands. Ten studies were conducted in preschool settings, with a preschool teacher being the most common delivery agent for the intervention. The interventions were mainly organised as small-group sessions, with three or four children per group. The mean dosage per week was 80 minutes and ranged from 24 to 120 minutes. The studies commonly applied shared book reading (reading aloud with the children), with target words embedded in the books. Standard care differed based on the setting and local conditions in each country or (pre)school. In some studies, the comparison groups received vocabulary instruction in preschool groups. Compared to standard care, the effect of L2 vocabulary interventions varied across outcome measures. For vocabulary measures including words that were taught in the intervention (proximal outcome measures), the intervention effects were large for both receptive L2 vocabulary (i.e. understanding of words; standardised mean difference (SMD) 0.97, 95% confidence interval (CI) 0.64 to 1.30; 4 studies, 1973 participants; very low-certainty evidence) and expressive L2 vocabulary (i.e. expressing or producing words; SMD 0.86, 95% CI 0.56 to 1.17; 6 studies, 1121 participants; very low-certainty evidence). However, due to some concerns in the overall risk of bias assessment, substantial heterogeneity, and wide CIs, we have limited confidence in these results. For language measures that did not include taught vocabulary (distal outcome measures), the intervention effects were small for receptive vocabulary (SMD 0.29, 95% CI 0.02 to 0.55; 6 studies, 1074 participants; low-certainty evidence) and probably made little to no difference to expressive vocabulary (SMD 0.10, 95% CI -0.02 to 0.23; 7 studies, 960 participants; moderate-certainty evidence). There was little to no intervention effect on L2 listening comprehension (SMD 0.19, 95% CI -0.31 to 0.68; 2 studies, 294 participants; very low-certainty evidence), but the evidence was uncertain, and the interventions probably increased L2 narrative skills slightly (SMD 0.37, 95% CI 0.14 to 0.59; 2 studies, 487 participants; moderate-certainty evidence). Only one study reported data on MLU, and we were unable to examine the effect of intervention on this outcome. The level of certainty of the evidence was downgraded mainly due to inconsistency and imprecision. We were unable to draw conclusions about socio-emotional well-being, or conduct the planned subgroup analyses to examine the second objective, due to lack of data. AUTHORS' CONCLUSIONS: Findings from this review suggest that, compared to standard care, vocabulary interventions may benefit children's L2 vocabulary learning but have little to no effect on their listening comprehension, though the evidence is uncertain. Vocabulary interventions probably improve the children's storytelling skills slightly. Due to the limited number of studies that met our inclusion criteria and the very low- to moderate-certainty evidence as a result of inconsistency and imprecision, implications for practice should be considered with caution. This review highlights the need for more high-quality trials (e.g. RCTs) of vocabulary interventions for L2 learners, particularly studies of learners outside the USA.


Assuntos
Comunicação , Vocabulário , Criança , Pré-Escolar , Humanos , Emoções , Cognição , Idioma
3.
J Child Psychol Psychiatry ; 58(10): 1132-1140, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28671266

RESUMO

BACKGROUND: Children with language comprehension difficulties are at risk of educational and social problems, which in turn impede employment prospects in adulthood. However, few randomized trials have examined how such problems can be ameliorated during the preschool years. METHODS: We conducted a cluster randomized trial in 148 preschool classrooms. Our intervention targeted language comprehension skills and lasted 1 year and 1 month, with five blocks of 6 weeks and intervention three times per week (about 75 min per week). Effects were assessed on a range of measures of language performance. RESULTS: Immediately after the intervention, there were moderate effects on both near, intermediate and distal measures of language performance. At delayed follow-up (7 months after the intervention), these reliable effects remained for the distal measures. CONCLUSIONS: It is possible to intervene in classroom settings to improve the language comprehension skills of children with language difficulties. However, it appears that such interventions need to be intensive and prolonged.


Assuntos
Compreensão/fisiologia , Intervenção Educacional Precoce/métodos , Transtornos da Linguagem/fisiopatologia , Transtornos da Linguagem/terapia , Avaliação de Resultados em Cuidados de Saúde , Instituições Acadêmicas , Pré-Escolar , Feminino , Seguimentos , Humanos , Masculino , Noruega
4.
J Eur Acad Dermatol Venereol ; 17(6): 699-701, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14761142

RESUMO

BACKGROUND: Erythema multiforme (EM) is an uncommon mucocutaneous disorder, characterized by widespread erythematous-oedematous targetoid lesions, considered as a reaction pattern to many different stimuli. OBSERVATION: Presentation is made of a classical EM eruption concomitant to an inflammatory, atypical dermatophytosis of the ala nasi, observed in a 37-year-old male at the Dermatology Department of Cagliari, Italy. METHODS: Laboratory investigations revealed normal complete blood count and biochemistry profile. A direct microscopic examination with 20% potassium hydroxide of the nasal skin scales and of the vibrissae indicated the presence of dermatophyte hyphae and spores invading the rhinothrix. Culture confirmed a Trycophyton mentagrophytes infection. Specific determination of antiviral immunity in the blood (TORCH) was negative for recent infections, while the cell-mediated response, investigated with a delayed skin multitest, showed a marked positivity for the tricophyton antigen. Systemic therapy with terbinafine (250 mg/day) led to complete clinical and mycological recovery of the atypical ringworm in 30 days. Multiforme lesions rapidly improved and completely disappeared in 7 days. CONCLUSIONS: ID reaction to a distant focus of dermatophyte infection very rarely presents as EM. The presented case fits all the essential criteria required for the diagnosis of an ID reaction. The atypical clinical presentation of the ringworm infection, with marked involvement of the intranasal hairs, seems to have induced an inflammatory allergic response, similar to that evoked by sycosis.


Assuntos
Dermatomicoses/imunologia , Eritema Multiforme/imunologia , Herpes Simples/imunologia , Adulto , Dermatomicoses/complicações , Dermatomicoses/diagnóstico , Dermatomicoses/tratamento farmacológico , Eritema Multiforme/complicações , Eritema Multiforme/diagnóstico , Seguimentos , Herpes Simples/complicações , Herpes Simples/diagnóstico , Humanos , Masculino , Naftalenos/uso terapêutico , Medição de Risco , Índice de Gravidade de Doença , Terbinafina , Resultado do Tratamento
6.
7.
Biochem Biophys Res Commun ; 190(2): 660-7, 1993 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-8381283

RESUMO

To understand how expression of IL-8 mRNA is regulated, we studied the effects of Staurosporine, H7, phorbol-myristate-acetate and Dexamethasone in human neutrophils subsequently treated with IFN-gamma. Our results can be summarized as follows: a) IL-8 mRNA steady state levels were enhanced in a dose dependent fashion by both Staurosporine and phorbol-myristate-acetate, were not influenced by H7, but were decreased by Dexamethasone; b) the negative effect of IFN-gamma on IL-8 mRNA accumulation was prevented by Staurosporine and phorbol-myristate-acetate, was not influenced by H7, and was potentiated by Dexamethasone; c) IL-8 mRNA induction caused by Staurosporine was accompanied by a time and dose dependent release of IL-8 into the PMN supernatants.


Assuntos
Alcaloides/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Interferon gama/farmacologia , Interleucina-8/genética , NADPH Oxidases , Neutrófilos/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Northern Blotting , Grupo dos Citocromos b/genética , Dexametasona/farmacologia , Sinergismo Farmacológico , Humanos , Isoquinolinas/farmacologia , Piperazinas/farmacologia , RNA Mensageiro/metabolismo , Estaurosporina , Superóxidos/metabolismo , Acetato de Tetradecanoilforbol/farmacologia
8.
J Exp Med ; 176(5): 1387-98, 1992 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-1357073

RESUMO

Natural killer cell stimulatory factor (NKSF), or interleukin 12 (IL-12), is a 70-kD heterodimeric cytokine composed of two covalently linked chains, p40 and p35. NKSF/IL-12 has multiple effects on T and NK cells and was originally identified and purified from the supernatant fluid of Epstein-Barr virus (EBV)-transformed human B lymphoblastoid cell lines. We have produced a panel of monoclonal antibodies against both chains of NKSF/IL-12. Some of these antibodies have neutralizing activity, and several combinations of them have been used to establish sensitive radioimmunoassays detecting the free p40 chain, the free p35 chain, or the p70 heterodimer. Using these reagents, we have determined that most EBV-transformed human B lymphoblastoid cell lines constitutively produce low levels of the p70 heterodimer and an excess of the free p40 chain, whereas Burkitt lymphoma-derived, T, myeloid, and many solid tumor-derived cell lines produce neither. Production of both p40 and p70 is increased several-fold upon stimulation of the EBV-transformed cell lines with phorbol diesters. The ability of supernatant fluids from unstimulated and phorbol diester-stimulated cell lines to induce interferon gamma (IFN-gamma) production from T and NK cells, one of the effects of NKSF/IL-12, parallels the levels of production of the p70 heterodimer, known to be the biologically active form of NKSF/IL-12. Staphylococcus aureus Cowan I strain (SAC) and other stimuli induce accumulation of p40 mRNA and production of both p40 and p70 by peripheral blood mononuclear cells (PBMC). The producer cells appear to include both adherent cells and nonadherent lymphocytes, possibly B cells. The supernatant fluids from SAC-stimulated PBMC mediate the typical functions of NKSF/IL-12 (i.e., IFN-gamma induction, mitogenic effects on T/NK blasts, enhancement of NK cell cytotoxicity) at concentrations of p70 similar to those at which recombinant NKSF/IL-12 mediates the same functions. Moreover, these activities are significantly inhibited by anti-NKSF/IL-12 antibodies. The neutralizing anti-NKSF/IL-12 antibodies also inhibit 85% of the IFN-gamma production in response to SAC, an NKSF/IL-12 inducer, and approximately 50% of the IFN-gamma production in response to non-NKSF/IL-12-inducers such as IL-2, phytohemagglutinin, and anti-CD3 antibodies. These results indicate that induced or constitutively produced NKSF/IL-12 has a major role in facilitating IFN-gamma production by peripheral blood lymphocytes.(ABSTRACT TRUNCATED AT 400 WORDS)


Assuntos
Interleucinas/biossíntese , Células Matadoras Naturais/efeitos dos fármacos , Leucócitos Mononucleares/metabolismo , Animais , Anticorpos Monoclonais/biossíntese , Linhagem Celular , Feminino , Interferon gama/biossíntese , Interleucina-12 , Interleucinas/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Radioimunoensaio
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