VACINAS, PARA QUE AS QUERO?

Em um momento em que os menos avisados suspeitam das vacinas, as autoridades em saúde pública e imunologia apresentam dados mostrando que, na realidade, as vacinas precisam, sim, ser inoculadas com mais frequência. Esse é o teor do artigo 'Quanto tempo duram as vacinas?', assinado por Jon Cohen e publicado na prestigiosa revista Science em abril de 2019. Nele, Cohen indaga, entre outros assuntos, por que o efeito protetor das vacinas contra a gripe dura tão pouco (em média, depois de 90 dias, a proteção começa a cair) e em outras, como as da varíola e da febre amarela, a ação é bem mais prolongada.

Alguns especialistas argumentam que certos vírus sofrem altas taxas de mutação e geram novos clones, que, por serem ligeiramente diferentes dos originais, não seriam reconhecidos pelas células do sistema imune. Mas, a coisa não é tão simples assim.

Ao estudar a caxumba (que ainda afeta os humanos), por exemplo, os epidemiologistas descobriram que a recorrência da doença acontece com mais frequência em uma determinada faixa etária (entre 18 e 29 anos de idade). Se a reinfecção dependesse apenas de mutações, todas as idades deveriam ser igualmente afetadas. Assim, o enigma perdura.

No entanto, o consenso entre os imunologistas especializados em vacinas é que, de fato, precisamos de mais exposição aos agentes infecciosos ou às próprias vacinas. Em outras palavras, no caso da gripe, teríamos que tomar doses seguidas da vacina a fim de aumentar seu efeito protetor. Em razão desses achados, os pesquisadores chegaram até acriticara decisão da Organização Mundial da Saúde (OMS) de recomendar que a vacina contra afebre amarela devesse ser inoculada apenas uma vez, isto é, seria uma vacina vitalícia.

A necessidade da exposição constante aos agentes infecciosos vai de encontro à hipótese do biólogo norte americano Jared Diamond que, em seu livro Armas, germes e aço, defende a ideia de que, ao longo da história, o sucesso dos conquistadores se deveu, em parte, ao fato de eles serem originalmente cosmopolitas e, dessa maneira, terem adquirido resistência imunológica aos agentes infecciosos da época. Mesmo resistentes, seriam portadores desses agentes, o que manteria a memória imunológica. Já os conquistados, grupo formado por populações menores, sucumbiriam ao confronto por não serem capazes dese defender tanto dos invasores humanos quanto daqueles microscópicos.

Embora o avanço nessa área seja promissor, o mecanismo que torna uma vacina mais duradoura ou não ainda segue sem resposta. Como afirma Cohen em seu artigo, "essa é uma pergunta de um milhão de dólares!" (aproximadamente, o valor do prêmio Nobel).

A despeito disso, ninguém deveria duvidar do poder das vacinas. Muito pelo contrário. A tendência atual no tratamento de doenças crônicas, como o câncer e a artrite reumatoide, é a imunoterapia. Um dia, quem sabe, teremos vacinas contra todos esses males.

_{Franklin Rumjanek}

VACINAS, PARA QUE AS QUERO?

Em um momento em que os menos avisados suspeitam das vacinas, as autoridades em saúde pública e imunologia apresentam dados mostrando que, na realidade, as vacinas precisam, sim, ser inoculadas com mais frequência. Esse é o teor do artigo 'Quanto tempo duram as vacinas?', assinado por Jon Cohen e publicado na prestigiosa revista Science em abril de 2019. Nele, Cohen indaga, entre outros assuntos, por que o efeito protetor das vacinas contra a gripe dura tão pouco (em média, depois de 90 dias, a proteção começa a cair) e em outras, como as da varíola e da febre amarela, a ação é bem mais prolongada.

Alguns especialistas argumentam que certos vírus sofrem altas taxas de mutação e geram novos clones, que, por serem ligeiramente diferentes dos originais, não seriam reconhecidos pelas células do sistema imune. Mas, a coisa não é tão simples assim.

Ao estudar a caxumba (que ainda afeta os humanos), por exemplo, os epidemiologistas descobriram que a recorrência da doença acontece com mais frequência em uma determinada faixa etária (entre 18 e 29 anos de idade). Se a reinfecção dependesse apenas de mutações, todas as idades deveriam ser igualmente afetadas. Assim, o enigma perdura.

No entanto, o consenso entre os imunologistas especializados em vacinas é que, de fato, precisamos de mais exposição aos agentes infecciosos ou às próprias vacinas. Em outras palavras, no caso da gripe, teríamos que tomar doses seguidas da vacina a fim de aumentar seu efeito protetor. Em razão desses achados, os pesquisadores chegaram até acriticara decisão da Organização Mundial da Saúde (OMS) de recomendar que a vacina contra afebre amarela devesse ser inoculada apenas uma vez, isto é, seria uma vacina vitalícia.

A necessidade da exposição constante aos agentes infecciosos vai de encontro à hipótese do biólogo norte americano Jared Diamond que, em seu livro Armas, germes e aço, defende a ideia de que, ao longo da história, o sucesso dos conquistadores se deveu, em parte, ao fato de eles serem originalmente cosmopolitas e, dessa maneira, terem adquirido resistência imunológica aos agentes infecciosos da época. Mesmo resistentes, seriam portadores desses agentes, o que manteria a memória imunológica. Já os conquistados, grupo formado por populações menores, sucumbiriam ao confronto por não serem capazes dese defender tanto dos invasores humanos quanto daqueles microscópicos.

Embora o avanço nessa área seja promissor, o mecanismo que torna uma vacina mais duradoura ou não ainda segue sem resposta. Como afirma Cohen em seu artigo, "essa é uma pergunta de um milhão de dólares!" (aproximadamente, o valor do prêmio Nobel).

A despeito disso, ninguém deveria duvidar do poder das vacinas. Muito pelo contrário. A tendência atual no tratamento de doenças crônicas, como o câncer e a artrite reumatoide, é a imunoterapia. Um dia, quem sabe, teremos vacinas contra todos esses males.

_{Franklin Rumjanek}

TEXTO V

Unlike reference grammars, activities handbooks, cultural or literary readers, audio or video ancillary materiais and computer software, foreign language textbooks are characterized by four major features that they have in common with texts in other subjects. They are:

1Principle-oriented. They provide the learner with basic principies of knowledge. Webster defines a textbook as a "book containing a presentation of the principies of a subject, a source providing an introduction or a basis." Larousse points to the "notion essentielles" given by a textbook.

2 Methodical. The organization and progression of textbooks is methodical. They embody the notion that knowledge is itemizable and classifiable and that learning is sequential and cumulative.

3. Authoritative. Textbooks are sources of authority (OLSON, 1980, p. 192). They are by essence normative (KONIGS, 1983, p. 400), above criticism. They present the language as it should be spoken and written by the learners, cultural information as it should be viewed and interpreted bythe reader. The idea that atext could contain misprints or even errors is inconceivable for most learners. By contrast with noneducational material, a foreign language text imparts knowledge that is viewed by its user as ultimately imperative, not declarative, knowledge.

4 Literal. Unlike a work of fiction, a textbook is usually intended to be taken literally, at face value. Everything is the way it is depicted and no other way: "Texts say what they mean and mean precisely neither more nor less than what they say" (Olson, 1980, p. 190).

_{Adaptado de: KRAMSCH, C. J. The Cultural Discourse of Foreign Language Textbooks. ln: TILIO, R.; FERREIRA, A. de J. lnnovations and Challenges in Language Teaching and Materiais Development. Campinas: Pontes, 2017.}

TEXTO V

Unlike reference grammars, activities handbooks, cultural or literary readers, audio or video ancillary materiais and computer software, foreign language textbooks are characterized by four major features that they have in common with texts in other subjects. They are:

1Principle-oriented. They provide the learner with basic principies of knowledge. Webster defines a textbook as a "book containing a presentation of the principies of a subject, a source providing an introduction or a basis." Larousse points to the "notion essentielles" given by a textbook.

2 Methodical. The organization and progression of textbooks is methodical. They embody the notion that knowledge is itemizable and classifiable and that learning is sequential and cumulative.

3. Authoritative. Textbooks are sources of authority (OLSON, 1980, p. 192). They are by essence normative (KONIGS, 1983, p. 400), above criticism. They present the language as it should be spoken and written by the learners, cultural information as it should be viewed and interpreted bythe reader. The idea that atext could contain misprints or even errors is inconceivable for most learners. By contrast with noneducational material, a foreign language text imparts knowledge that is viewed by its user as ultimately imperative, not declarative, knowledge.

4 Literal. Unlike a work of fiction, a textbook is usually intended to be taken literally, at face value. Everything is the way it is depicted and no other way: "Texts say what they mean and mean precisely neither more nor less than what they say" (Olson, 1980, p. 190).

_{Adaptado de: KRAMSCH, C. J. The Cultural Discourse of Foreign Language Textbooks. ln: TILIO, R.; FERREIRA, A. de J. lnnovations and Challenges in Language Teaching and Materiais Development. Campinas: Pontes, 2017.}

TEXTO V

Unlike reference grammars, activities handbooks, cultural or literary readers, audio or video ancillary materiais and computer software, foreign language textbooks are characterized by four major features that they have in common with texts in other subjects. They are:

1Principle-oriented. They provide the learner with basic principies of knowledge. Webster defines a textbook as a "book containing a presentation of the principies of a subject, a source providing an introduction or a basis." Larousse points to the "notion essentielles" given by a textbook.

2 Methodical. The organization and progression of textbooks is methodical. They embody the notion that knowledge is itemizable and classifiable and that learning is sequential and cumulative.

3. Authoritative. Textbooks are sources of authority (OLSON, 1980, p. 192). They are by essence normative (KONIGS, 1983, p. 400), above criticism. They present the language as it should be spoken and written by the learners, cultural information as it should be viewed and interpreted bythe reader. The idea that atext could contain misprints or even errors is inconceivable for most learners. By contrast with noneducational material, a foreign language text imparts knowledge that is viewed by its user as ultimately imperative, not declarative, knowledge.

4 Literal. Unlike a work of fiction, a textbook is usually intended to be taken literally, at face value. Everything is the way it is depicted and no other way: "Texts say what they mean and mean precisely neither more nor less than what they say" (Olson, 1980, p. 190).

_{Adaptado de: KRAMSCH, C. J. The Cultural Discourse of Foreign Language Textbooks. ln: TILIO, R.; FERREIRA, A. de J. lnnovations and Challenges in Language Teaching and Materiais Development. Campinas: Pontes, 2017.}

TEXTO V

Unlike reference grammars, activities handbooks, cultural or literary readers, audio or video ancillary materiais and computer software, foreign language textbooks are characterized by four major features that they have in common with texts in other subjects. They are:

1Principle-oriented. They provide the learner with basic principies of knowledge. Webster defines a textbook as a "book containing a presentation of the principies of a subject, a source providing an introduction or a basis." Larousse points to the "notion essentielles" given by a textbook.

2 Methodical. The organization and progression of textbooks is methodical. They embody the notion that knowledge is itemizable and classifiable and that learning is sequential and cumulative.

3. Authoritative. Textbooks are sources of authority (OLSON, 1980, p. 192). They are by essence normative (KONIGS, 1983, p. 400), above criticism. They present the language as it should be spoken and written by the learners, cultural information as it should be viewed and interpreted bythe reader. The idea that atext could contain misprints or even errors is inconceivable for most learners. By contrast with noneducational material, a foreign language text imparts knowledge that is viewed by its user as ultimately imperative, not declarative, knowledge.

4 Literal. Unlike a work of fiction, a textbook is usually intended to be taken literally, at face value. Everything is the way it is depicted and no other way: "Texts say what they mean and mean precisely neither more nor less than what they say" (Olson, 1980, p. 190).

_{Adaptado de: KRAMSCH, C. J. The Cultural Discourse of Foreign Language Textbooks. ln: TILIO, R.; FERREIRA, A. de J. lnnovations and Challenges in Language Teaching and Materiais Development. Campinas: Pontes, 2017.}

TEXTO IV

CHALLENGES IN TEACHER TECHNOLOGY PREPARATION

Unfortunately, teacher preparation for technology use in language education has faced many challenges: it is still often neglected completely or focused on learning to use existing technologies rather than looking forward to the ways in which cutting-edge technologies can enhance or revolutionize teaching and learning. With the many demands of language teacher preparation, technology use is often sacrificed but is becoming increasingly important across the spectrum of language teacher preparation. The literacy practices associated with these emerging domains are likelyto be unique from established practices invarious ways. This is an important consideration regarding teacher preparation. Guikema and Menke (2014) discussed the importance of incorporating current and emerging forms of digital literacy in teacher preparation. There are many other aspects of teacher preparation impacted by these developments. Many researchers have observed an appreciation for the importance of using technology in teaching (Hlas, Conroy, & Hildebrandt, 2017; Kessler, 2006). However, there has long been a reluctanceto usetechnology for language teaching even when teachers have received preparation. Researchers have observed that the preparation that teachers receive is often inadeq uate, inappropr iate, irrelevant, or outdated (Kessler, 2010 ; Williams, Abraham, & Bostelmann, 2014). There have been numerous suggestions for howto address this disconnect, but the challenge persists.

_{Adaptado de: KESSLER, G. Technology andlhe future of language teaching. Foreign Language Annals. 2018; 1-14.}

TEXTO IV

CHALLENGES IN TEACHER TECHNOLOGY PREPARATION

Unfortunately, teacher preparation for technology use in language education has faced many challenges: it is still often neglected completely or focused on learning to use existing technologies rather than looking forward to the ways in which cutting-edge technologies can enhance or revolutionize teaching and learning. With the many demands of language teacher preparation, technology use is often sacrificed but is becoming increasingly important across the spectrum of language teacher preparation. The literacy practices associated with these emerging domains are likelyto be unique from established practices invarious ways. This is an important consideration regarding teacher preparation. Guikema and Menke (2014) discussed the importance of incorporating current and emerging forms of digital literacy in teacher preparation. There are many other aspects of teacher preparation impacted by these developments. Many researchers have observed an appreciation for the importance of using technology in teaching (Hlas, Conroy, & Hildebrandt, 2017; Kessler, 2006). However, there has long been a reluctanceto usetechnology for language teaching even when teachers have received preparation. Researchers have observed that the preparation that teachers receive is often inadeq uate, inappropr iate, irrelevant, or outdated (Kessler, 2010 ; Williams, Abraham, & Bostelmann, 2014). There have been numerous suggestions for howto address this disconnect, but the challenge persists.

_{Adaptado de: KESSLER, G. Technology andlhe future of language teaching. Foreign Language Annals. 2018; 1-14.}