Students’ Interest in Speaking English and How It relates to Their Speaking Achievement

Abstract               The background of this research was the need to investigate the interest in speaking English and speaking English achievement. It mainly aimed to study the relationship between the two variables. The study was quantitative research using descriptive, inferential, correlational, and survey methods conducted upon students at a private senior high school. The findings of the study showed that the students are interested in speaking English and that their English-speaking achievement is good. The last finding showed that there is a correlation between the students’ interest in speaking English and their English-speaking achievement.   Keywords—interest, achievement, interest in speaking, speaking achievement   Abstrak Latar belakang penelitian ini adalah perlunya diteliti minat berbicara bahasa Inggris dan prestasi berbahasa Inggris. Ini terutama bertujuan untuk mempelajari hubungan antara kedua variabel. Penelitian ini merupakan penelitian kuantitatif dengan menggunakan metode deskriptif, inferensial, korelasional, dan survei yang dilakukan pada siswa sebuah sekolah menengah atas swasta. Temuan penelitian menunjukkan bahwa siswa tertarik untuk berbicara bahasa Inggris dan bahwa prestasi berbahasa Inggris mereka baik. Temuan terakhir menunjukkan bahwa ada korelasi antara minat siswa dalam berbicara bahasa Inggris dan prestasi berbahasa Inggris mereka.     Kata kunci—minat, prestasi, minat berbicara bahasa Inggris, prestasi berbicara bahasa Inggri

Membrane-enclosed multienzyme (MEME) synthesis of 2,7-anhydro-sialic acid derivatives

Naturally occurring 2,7-anhydro-alpha-N-acetylneuraminic acid (2,7-anhydro-Neu5Ac) is a transglycosylation product of bacterial intramolecular trans-sialidases (IT-sialidases). A facile one-pot two-enzyme approach has been established for the synthesis of 2,7-anhydro-sialic acid derivatives including those containing different sialic acid forms such as Neu5Ac and N-glycolylneuraminic acid (Neu5Gc). The approach is based on the use of Ruminoccocus gnavus IT-sialidase for the release of 2,7-anhydro-sialic acid from glycoproteins, and the conversion of free sialic acid by a sialic acid aldolase. This synthetic method, which is based on a membrane-enclosed enzymatic synthesis, can be performed on a preparative scale. Using fetuin as a substrate, high-yield and cost-effective production of 2,7-anhydro-Neu5Ac was obtained to high-purity. This method was also applied to the synthesis of 2,7-anhydro-Neu5Gc. The membrane-enclosed multienzyme (MEME) strategy reported here provides an efficient approach to produce a variety of sialic acid derivatives

Human recombinant anti-thyroperoxidase autoantibodies: in vitro cytotoxic activity on papillary thyroid cancer expressing TPO

International audienceBACKGROUND: Thyroid cancers are difficult to treat due to their limited responsiveness to chemo- and radiotherapy. There is thus a great interest in and a need for alternative therapeutic approaches. RESULTS: We studied the cytotoxic activity of anti-thyroperoxidase autoantibodies (anti-TPO aAbs, expressed in baculovirus/insect cell (B4) and CHO cells (B4') or purified from patients' sera) against a papillary thyroid cancer (NPA) cell line. Anti-TPO aAbs from patients' sera led to a partial destruction of NPA cell line by complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC) and exhibited an anti-proliferative activity. Comparison of the cytotoxic activity of anti-TPO aAbs shows that B4' induced an anti-proliferative effect and a better ADCC than B4, but a lower one than anti-TPO aAbs from patients' sera. Antibody-dependent cell-mediated cytotoxicity was increased when human peripheral blood mononuclear cells were used as effector cells, suggesting that FcgammaRs, CD64, CD32 and CD16 are involved. Indeed, anti-TPO aAbs from patients' sera, but not B4 and B4', exhibited CDC activity. CONCLUSIONS: These data indicate that anti-TPO aAbs display moderate ADCC and anti-proliferative activities on NPA cells; IgG glycosylation appears to be important for cytotoxic activity and ADCC efficiency depends on FcgammaR-bearing cells. Finally, recombinant human anti-TPO aAbs cannot yet be considered as an optimal tool for the development of a novel therapeutic approach for thyroid cancer

Transient glyco-engineering to produce recombinant IgA1 with defined N-and O-glycans in plants

[EN] The production of therapeutic antibodies to combat pathogens and treat diseases, such as cancer is of great interest for the biotechnology industry. The recent development of plant-based expression systems has demonstrated that plants are well-suited for the production of recombinant monoclonal antibodies with defined glycosylation. Compared to immunoglobulin G (IgG), less effort has been undertaken to express immunoglobulin A (IgA), which is the most prevalent antibody class at mucosal sites and a promising candidate for novel recombinant biopharmaceuticals with enhanced anti-tumor activity. Here, we transiently expressed recombinant human IgA1 against the VP8* rotavirus antigen in glyco-engineered XT/FT Nicotiana benthamiana plants. Mass spectrometric analysis of IgA1 glycopeptides revealed the presence of complex biantennary N-glycans with terminal N-acetylglucosamine present on the N-glycosylation site of the CH2 domain in the IgA1 alpha chain. Analysis of the peptide carrying nine potential O-glycosylation sites in the IgA1 alpha chain hinge region showed the presence of plant-specific modifications including hydroxyproline formation and the attachment of pentoses. By co-expression of enzymes required for initiation and elongation of human O-glycosylation it was possible to generate disialylated mucin-type core 1 O-glycans on plant-produced IgA1. Our data demonstrate that XT/FT N. benthamiana plants can be engineered toward the production of recombinant IgA1 with defined human-type Nand O-linked glycans.This work was supported by a grant from the Austrian Federal Ministry of Transport, Innovation and Technology (bmvit) and Austrian Science Fund (FWF): TRP 242-B20 and by the Austrian Research Promotion Agency (Laura Bassi Center of Expertise "Plant produced Bio-Pharmaceuticals" Grant Nr. 822757).Dicker, M.; Tschofen, M.; Maresch, D.; Koenig, J.; Juarez, P.; Orzáez Calatayud, DV.; Altmann, F.... (2016). Transient glyco-engineering to produce recombinant IgA1 with defined N-and O-glycans in plants. Frontiers in Plant Science. 7(18):1-12. https://doi.org/10.3389/fpls.2016.00018S11271

Immune responses in mice to different noncovalent complexes of meningococcal B polysaccharide and outer membrane proteins

Noncovalent complexes of meningococcal group B polysaccharide and outer membrane proteins (OMPs) from serotypes 2a, 2b, 6, 8, and 15 were made either by coextraction of the two components from culture supernatants or by separate preparation of both OMPs and B polysaccharide with subsequent mixing of the two components. The former method showed a markedly greater degree of binding of B polysaccharide to OMPs, a less heterogeneous composition of OMPs, and a lower lipopolysaccharide content. Immunization of mice with these complexes showed that a higher degree of binding of B polysaccharide to OMPs resulted in a higher anti-B response. Western blotting (immunoblotting) and solid-phase radioimmunoassay techniques confirmed that antibody cross-reactions occur among OMP serotypes. The occurrence of common T-cell determinants between OMP serotypes was suggested when mice primed with a type 6 OMP complex and challenged with a homologous or heterologous serotype complex responded with significantly higher anti-B titers than unprimed animals. These memory T cells persisted for at least 12 months in mice.</jats:p