SciELO - Scientific Electronic Library Online

vol.47 issue5Perinatal mortality in the municipality of Salvador, Northeastern Brazil: evolution from 2000 to 2009 author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista de Saúde Pública

Print version ISSN 0034-8910

Rev. Saúde Pública vol.47 no.5 São Paulo Oct. 2013 

Special Article

Institutionalization of Public Health Care in Sao Paulo between 1930 and 1940

André MotaI 

Lilia Blima SchraiberII 

I Museu Professor Carlos da Silva Lacaz . Faculdade de Medicina . Universidade de São Paulo . São Paulo , SP , Brasil

II Departamento de Medicina Preventiva . Faculdade de Medicina . Universidade de São Paulo . São Paulo , SP , Brasil


The aim of the study was to interpret and understand the institutionalization of public health care in the state of Sao Paulo over the years 1930-1940, based on the history of medical specialties. The methodology involved analysis of new sources of documents, which were compared with the existing literature, thereby leading to identification of new indices relating to the issue of eugenics and the presence of physicians’ religious beliefs as a social movement. As physicians became public health experts, they proposed a project to elevate the Brazilian race, by merging the hygienist discourse with sanitary actions. Sao Paulo sought primacy in this project, believing that this was a State already constituted by a race of “historically healthy men”. Religious beliefs influenced the debate and the decisions of that time with regard to the established order within public health. In this manner, it could be shown that, historically, public health discourse was constituted by merging technical-scientific issues with political-ideological and cultural issues, producing a mixture of different interests and corporative perspectives of the profession.

Key words: Public Health; Social Medicine; Eugenics; Institutionalization, history


The field of health care has undergone countless transformations in the 20 th century, when various specialties were instituted. These specialties were almost always taken as specific branches of knowledge that grew broader and deeper at rhythms and in directions which seem to be the result of a natural order of disease and/or health care technologies. At times, they are understood to be a technical division of scientific knowledge and their social, political, economic or corporate-professional motives remain hidden.

This mode of approaching history can be synthesized in the formulation of what Conti 4 refers to as a doctors’ view of medicine: changing means but unchanging ends, as if the knowledge or equipment and other technology change over time, but the ultimate aim of medicine, to cure disease, does not change. Critics of the author, in contrast, highlight the mutability of these ends.

Taking Conti 4 as reference, the aim of this study was to interpret and understand the historical changes that led to public health having new purposes for its practice and new fields of expertise, as part of the history of medical specialties in São Paulo between 1930 and 1940.

The article examines how the institutionalization of public health became involved with polar eugenic concepts that referred not only to the area of the biologist, such as strengthening the human race using medical and health measures, but also to the ideological notion of racial purity. In this particular involvement with eugenics, the religion of some doctors, represented by the Catholicism of the time, played an important role. If public health was an important State resource in constructing the nation’s prosperity, major scientific-political-ideological and cultural questions were present in its development as a specialty, even as part of the contribution of medicine in constructing the Estado Moderno – Modern State. 6 , 11

Starr 17 shows the distinction between the medical profession and other scientific professions due to the complexity of its image and expectations regarding the technological and scientific instruments of their work. This distinction is engendered in a complex field of actions and reactions, sometimes polarizing them against other professionals who “threaten” areas instituted by medicine, sometimes materializing as an “internal” struggle within the profession through confrontations between scientific, practical and political paradigms.

The doctor emerged as an organic intellectual, able to interact on two levels of the social structure: as an intellectual of a specific science and as a producer of symbols related to his profession. Historically, however, he has been circumscribed in an area of rifts, corporate reorganization and political and symbolic dissention. 1 For medicine and its institutions, the period of 1930-1940 ushered in an era in which a new political order was at stake, de-structuring the power of the oligarchy and the elite, among them doctors. The reactions of the profession should be understood within this complex context, involving the historicity of the events interlaced with the internal technical and scientific dimensions of the profession itself.

This methodological approach allows us to grasp how doctors determined corporate, scientific and political redefinitions, as agents of medicine characterized by the extent of their intellectual and symbolic capital. Part of this movement resulted in the introduction of related eugenic concepts, considered to be scientifically based, into various discourses in the field of the population’s health. Catholicism occupied a surprising place in health, even having repercussions on the eugenic tenets that would be adopted.

Primary documental sources 5 , 15 , a , b , c , d , e , f , g , h were used to analyze the establishment of public health as a specialty. In these sources, we sought traces of the social context of this knowledge and specific actions, the moment in time was also that in which the Brazilian Estado Moderno was constructed.


From 1930 onwards, medicine was reorganized, privately owned surgeries practicing freely. A technological medicine, with increasingly technological based arrangements and with medical care gradually becoming more entrepreneurial, emerged 16 resulting in great internal tension within the profession. 11 In 1922, countless divergences between doctors were demonstrated in the National Practitioners Congress, albeit unified by the effort to exert ever greater control on medical professionals and the veto of the various medical and curative practices then in existence. 14

This dispute was apparent in the curricula of the medical faculties: “by proposing the inclusion of this or that discipline in the medical curriculum, different sectors of the profession aimed to create space for their specialty to be recognized and valued”. 14 The requested actions took on a different tone with regards other occupations that rivalled the medical profession. How to deal with pharmacists, midwives, nurses, healers, spiritualists and their practices? “In each of these arenas, a different type of conflict took place, but with the same basic objective: to limit the field of these practices in order to ensure the sovereignty and authority of the doctor in the health care service market”. 14

It was a contest between the diverse practices carried out by the hegemony of scientific and technological medicine, grounded in clinical pathology, which characterizes the Biomedicine system. Although some existing practices had been approached as Biomedicine “specialties” (such as homeopathy, today recognized as another medical system and not a Biomedicine specialty) 8 , in the above mentioned congress there were also disputes between schools of thought on treatment within Biomedicine itself.

It is in this context that the “specialty” appeared as the driving force behind policies in research, in clinical and health practice, reorganizing scientific, medical-care and prophylactic and health institutions. The more general type of professional was gradually overtaken by the specialist, more technical and specific, as a professional able to provide medical care in urban and rural centers and with new forms of social production in the health care area.

In Sao Paulo, the area of public health was institutionalized at the end of the 19 th century, but the transformations of the first decade of the 20 th century, be they on an urban level or new policies aimed at the interior of the state, led to the doctor Geraldo de Paula Souza becoming the director of the Health service in 1922, with the aim of establishing a public health model as proposed by the Rockefeller Foundation:

“[...] as a result of this new health praxis, the doctor proposed solutions to various health problems faced by the city of São Paulo [...] Among the problems cited by the doctor, we highlight his concern with the water supply of São Paulo, proposing the construction of a new pipeline in Ribeirao Claro and collection and chlorination of water from the river Tietê during times of drought, until the new water mains are completed” 2 (p. XVIII).

Paula Souza changed the prevailing technical-care model, valued the formation of a single general administratively decentralized and regionalized outpatient network and proposed a new type of service: the Health Center. 9 Measures such as training health care educators and professionals specializing in hygiene and controlling parasites, local endemic disease and infant mortality were decisive to the further development of health and hygiene. 13 In the Third Brazilian Hygiene Congress, in 1926, Paula Sousa stated that the following aspects of public health were the State’s obligation:

“providing sanitation and resolving the problem of its habitability. Hygiene itself, which depends much more on the understanding of each person, on the individual’s own obligations regarding their health and, at the same time, on the understanding of their duties to the community (…) leads to men who are health aware.” g (p. 59).

If these measures in the field of health should have been put into practice, the absence of the “health doctor” as a key worker in the area and “specialized professional” was resented. From that moment, public health came to be conceived as a medical specialty, albeit in the hands of others. The public health specialty would be gradually and slowly established, making room for other branches of medicine to treat health education as part of their knowledge and actions. In the words of Paula Souza:

“The health profession does not, in fact, exist in Brazil. With very rare exceptions, public health activities are handed over to the performance of non-specialist doctors, who treat the task of sanitation as the smallest part of their work. Those few who do specialize come to see the impossibility of carrying out truly effective work, due to the passive resistance of the non-specialized masses” g (p. 65).

Constructing a “new nationality” and a “true Brazilian”, a central issue in establishing sanitarism as a specialty, can also be found in the interpretation of thinkers and social scientists. It involved different fields of knowledge and fed the racial and eugenic debate, which so strongly marked this period of history, in order to answer the question: who are we?

The discursive poles in the sociological and historical field had some aspects particular to Sao Paulo by defending a white and racially superior ‘paulista’ – citizen of Sao Paulo. Those of African descent, considered “inferior”, would be absent from the original formation of the paulista population, in the same way as some immigrants, considered “degenerate and invasive scum” would be restricted by the whitening and eugenic paulista project. Such discourse would be incorporated into the health thinking of the period.

During the 1 st Eugenics conference, held during the centenary celebrations of the Academia Nacional de Medicina , in Rio de Janeiro between July 1 and July 7, 1929, the doctor and psychiatrist Antonio Carlos Pacheco e Silva from Sao Paulo made a speech in which the basis of eugenics were treated as a paulista effort.

In his opinion, Sao Paulo concerned itself with improving the Brazilian race, stating “with the real pride of a paulista ”, that the first eugenic society had been founded in that state, it being

“the same state which today sends to this congress a humble representative with no credentials except having the votes of thousands of paulistas , from different races, but baked under the same sun, cemented by the same beliefs, unified by the same language, moved by one single, common ideal – that of the grandeur of the Brazilian nation and the strength of its children” f (p. 1).

From a health point of view, by incorporating eugenics as a medical term, strategies were demarcated in the search for the ideal human, recognized in their individuality to be modified. It was said that not all had the same chance of rising above their state, which was deemed morbid and degenerate. Understood as a scientific technology, environmental eugenics, as well as the measures that aimed to restrict individuals, required long debates and ended in major subdivisions.

From obstetrics to surgery, from health practices to experience established by psychiatrists, all incorporated eugenics, albeit interpreted in diverse and even conflicting forms. This clash between “eugenics” had political, philosophical, religious and scientific ramifications, converging on two central aspects: those who understood that environmental actions were capable of equating to the production of a “good man” (positive or environmental eugenics, the public health definition) and those who regarded heredity and restriction as the only way to racial improvement (negative or restrictive eugenics). This scientific field is undermined by various readings and actions, which sought, in myths of origin and modernizing innovations, to bring to light human racial superiority.

Stepan 18 produced a pioneering thesis on eugenics in Latin America and highlighted national peculiarities. It refuted the predominant view in the US and Europe that the case of Latin America would be a mere copy and showed how a neo-Lamarckian vision of eugenics was the cornerstone in the specific application of this debate. France was the hub from which the most commonly adopted version of eugenics radiated, leading to health and preventative actions being the ideal choice in shaping the population 18 (p. 14).

For this type of eugenics, based on factors influenced by sanitarism 3 and by hygienist propaganda, 12 such actions can intervene in individuals’ physical and mental development. This discourse gained a privileged space in Education and Law. In public health, it was of fundamental importance in childhood health care and child care. It came to occupy a special place on the medical agenda, merging children’s health care with heredity and, thus, with national destiny itself. This focus on childhood also had repercussions on obstetrics, with infantilism colonizing the construction of maternal health care, one of the historical roots of later reproductive health, centered on pre-natal hygiene, aimed at women seen primarily in their role as mothers. 10

Eugenic feuds found a Catholic presence involved in the business of the medical profession, especially at the moment in which sanitarism occupied a privileged position in the State’s health care policies. Translated through its normalizing habits and customs, as well as its preventative character and its eugenic stamp, this profile made room for many Catholic tenets to be discussed before the actions of the doctors. After lengthy disputes, specialization became increasingly more corporate and sanitarism gained increasing state power. Catholicism approached this debate, placing special importance on those that touched on issues deemed to be within its sphere of action, above all those that involved the family.

The commitment to introduce the dogmatic bases of the religion into medical specialties gained force within the profession. Human understanding of disease and death, so exercised in 19 th century medical reports, created the effect of reality in tales of suffering and invited reparative actions. Humanitarianism, even as narrated in the glacial language of medical science, 7 gained new elevation in descriptions with a Christian slant.

Medical clergymen represented the Church within the profession even in this period of specialization. However, it was the lay doctors who were responsible for divulging its precepts as “Science”, recommending ways of “living well” based on hygienist (sanitarist) and “spiritually elevated” attitudes.

Scientific conquests need no longer be a cause of worry to Catholicism, as:

“The Eternal Truth, source of all wisdom, is not subject to error, leaving the Church calm and trusting; as legitimate and true Science cannot be in disagreement with the word of God. Thus, we are filled not with fear but with enthusiasm and, jubilantly, we accompany the work of the researchers with real consideration and interest and, not infrequently, with valuable contributions” a (p. 25).


The relationship between Catholic thinking and eugenic sanitarism came to be based on the concept of the human body as a mold created by divine will and on belief in the value of healthy but, above all, spiritual, families:

“In all of creation, there is nothing more beautiful than a healthy, symmetrically developed human body, gifted with a well-balanced intelligence, which manifests itself in all its actions. In the beginning, man was made upright and was crowned in honor and glory, able to speak face to face with his creator. Gifted with morals and elevated faculties of reasoning, and possessing a face on which elevated mental impressions were reflected, a man was a being far above other creatures” 15 (p. 22-23).

“Family health” and its heritability were conceptualized as follows, in the words of the doctor Celestino Bourroul, from Sao Paulo, Chair of Tropical Medicine in the Faculty of Medicine, Universidade de São Paulo :

“this inheritance that our first fathers sadly bequeathed to us through original sin, so well demonstrated by the bible passage: Noah drank the juice of the vine and his children were born with sharp teeth, in other words, with a taste for alcohol – an inheritance well studied and proven in Biology” i (p. 188).

Environmental eugenics was taken as a health and hygiene tool, able to build a “new humanity” and a “new flock”. This would be its motto. Defending “one type” of eugenics was a way for Catholicism to take part in the debate, defending its prerogatives at the same time as it attacked the opposing camp, i.e., postulations advocating birth control through compulsory sterilization. This issue would involve part of health thinking.

Family would become a concern of restrictive eugenics, in the sense of guaranteeing good offspring for the nation, but with one important difference: restrictions to matrimony and, if possible, sterilization of those deemed to be degenerates. This more individualizing view, distancing itself from what would come to be public health with its collective perspective, provoked reactions from the defenders of eugenic sanitarism, especially with a Catholic bias. This occurred as it touched on an area that the Church defended as its own and had family health and breeding as its central axes.

The clash between areas of medical-eugenic rationality and medical-Catholicism in Sao Paulo were examples of the tension that enveloped the eugenic project for shaping the Brazilian race. Antonio Carlos Pacheco e Silva, an ardent defender of restrictive and compulsory eugenic methods, including sterilization, gave evidence of the dispute surrounding that issue in his speech to the Constituent Assembly of 1934. In his opinion, the Church could not be opposed to restrictive eugenics, as sterilizing individuals was something that had occurred in the past. He recalled Matthew’s Gospel, chapter XIX, verse 12, which says:

“There are eunuchs who were born like that from their mother’s womb; and there are eunuchs who were so made by other men; and there are eunuchs who castrate themselves, for the love of heaven. He who can understand this understands it” e (p. 107).

Going still further, he gave the primacy in castrations to the Catholic Church, stating that “Pope Benedict XIV authorized the eliminations of certain organs from the boys who sang in the Sistine Chapel, enabling them to keep their soprano voices” e (p. 107).

In his book, Eugenia , Octavio Domingues, geneticist and professor in the Escola de Agricultura Luiz de Queiroz , attempted to persuade Catholics with arguments on the theories of genetic improvement and on presenting the best strains of humanity. He claimed to have identified an ideal eugenic type, listing scientific figures and saints as its representatives. According to him, a eugenically shaped man would be:

“[...] a humane genius, as conquering, ambitious geniuses do not benefit humanity when the benefits are balanced against the shadow of the immense ill they spread, if they can, in truth, be considered great men, they are not human models to be multiplied. A eugenic genius would be Pasteur, Laennec, Darwin, Saint Francis of Assisi, Saint Vincent de Paul – morally resplendent geniuses not to be compared with those who worked for their own gain, aiming at what they could achieve for themselves – ambitious intelligent and knowledgeable – but not humane, very ordinary animals” 5 (p. 241).

In response, he received a letter from Alceu da Silveira, a representative of the Catholic Church, which he published in his book. In the letter, Silveira accused him of a false alliance with religion, stressing the Pope’s words on the meaning of life, but, at the end, giving examples of eugenic activities of which Catholicism did not approve, such as pre-nuptial testing, sterilization and birth control:

“[...] in the first case, it is a violence incomparable with any just understanding – neither duties such as taxes, which are intrinsic things, nor the death penalty, which punishes the guilty, and not the innocent, as in this case. A childless union animalizes, takes away love. If it is voluntary, modern self-indulgence and selfishness will inflict terrible injury on the life of the country. Do not tell me there are too many mouths to feed and not enough food. This is the imbalance in the liberal economy, which is not strongly and intelligently led, sharing with everyone, except the natural property rights of those who have it” 5 (p. 313-314).

Those doctors who defended medicine under Catholic precepts denounced the sterilization of so-called “lepers” proposed by the restrictive eugenicists. The paulista journal Viver! published a response in favor of advocates of eugenic sanitarism. The leprosy specialist Enéias de Carvalho Aguiar, who would become the first superintendent of the Hospital das Clínicas , Sao Paulo, in 1944, presented work that proved:

“[...] the daughter of the lepers is not born with the infection and, if she is quickly taken away from the sick parents, will have the same chances as any other to grow, live and die without contracting the disease from which her parents suffered when she was brought into the world” h (p. 2).

Thus the Asylo de Santa Terezinha and the Preventório de Jacareí asylums collected more than 300 children born to leprosy suffers and kept them separate from their parents from birth. Carvalho Aguiar observes: “To laymen, and even to non-specialist doctors, this assertion seems bold, but what we do is based on experience and on facts” h (p. 2).


The quest to understand the outlines that shaped health care practices leads us to positions that were historically presented and defended. Eugenics had ample space for its dissemination in various spheres, mainly involving the medical profession. There was a mixture of discourses from different fields of knowledge: on the issues of eugenics, religious beliefs influenced the way that eugenics was composed together with health and medicine itself.

For medicine and for sanitarism, these other types of knowledge and even nonscientific beliefs offered specific purposes of intervention in the health and disease of the “Brazilian people.” Thus, in a way specific to the socio-historical context of the years 1930-1940, medical practice and health clothed themselves in a specific historicity as regards their objectives such as social practices: the health and healing products to be achieved through their technical and scientific interventions were effectively redefined in the process of building specialties in medicine and public health.

Guided and influenced by factors influenced by sanitarism, eugenics believed that its actions would be capable of intervening in physically and mentally shaping individuals. In the medical field it was based mainly on children’s health care, merging health with heredity and with national destinies themselves. This started a process of incorporating dimensions of normality or pathology into national life and the lives of citizens, extending into various spheres of social construction and, in particular, the family. Catholic doctors were important spokespeople in this process.

The state of Sao Paulo laid claim to the privilege of a superior race already adjusted to new times, able to put Brazil on the track of progress. However, the arrival of migrants and immigrants who disembarked in a systematic and uncontrolled manner brought a new issue: it opened another space for the discourse of restriction of those who might “pollute the race of giants” made, according to the paulista version of their origins, from among the “Indian races “ and “daring Portuguese” when they planted their roots here. But this new issue fell to the following decades, posing a challenge to health control within specialized knowledge.


. Bourdieu P. A economia das trocas simbólicas. 5. ed. São Paulo: Perspectiva; 2004. [ Links ]

. Campos C. São Paulo pelas lentes da higiene: as propostas de Geraldo de Paula Souza para a cidade. São Paulo: Rima; 2002. [ Links ]

. Castro Santos LA. Poder, ideologias e saúde no Brasil da Primeira República: ensaios de sociologia histórica. In: Hochman G, Armus D, organizadores. Cuidar, controlar, curar: ensaios históricos sobre a saúde e doença na América latina e Caribe. Rio de Janeiro: Editora da Fiocruz; 2004. [ Links ]

. Conti L. Estrutura social y medicina. In: Aloisi M, Berlinguer G, Conti L, Massuco-Costa A, Misiti R, Mondella F, et al. Medicina y Sociedad. Barcelona; 1972. p. 287-310. [ Links ]

. Domingues O. Eugenia: seus propósitos, suas bases, seus meios. São Paulo: Companhia Editora Nacional; 1942. [ Links ]

. Freidson E. Profissão Médica: um estudo de sociologia do conhecimento aplicado. São Paulo: Editora da UNESP; 2008. [ Links ]

. Laqueur TW. Corpos, detalhes e a narrativa humanitária In: Hunt L. A nova história cultural. São Paulo: Martins Fontes; 2001. p.239-78. [ Links ]

8.  . Luz MT. Medicina e racionalidades médicas: estudo comparativo da medicina ocidental contemporânea, homeopática, tradicional chinesa e ayurvédica. In:Canesqui AM. Ciências Sociais e Saúde para o Ensino Médico . São Paulo: Hucitec; 2000. p. 181-99. [ Links ]

. Mendes-Gonçalves RB. Tecnologia e organização social das práticas de saúde: características tecnológicas do processo de trabalho na Rede Estadual dos Centros de Saúde de São Paulo. São Paulo: Hucitec; 1994. [ Links ]

. Mota A, Schraiber LB. Infância e saúde: perspectivas históricas. São Paulo: Hucitec; 2009. [ Links ]

11.  . Mota A, Schraiber LB. Mudanças corporativas e tecnológicas da medicina paulista, nos anos de 1930. Hist. Cienc Saude-Manguinhos . 2009;16(2):345-60. DOI:10.1590/S0104-59702009000200004. [ Links ]

. Mota A. Quem é bom já nasce feito: sanitarismo e eugenia no Brasil. Rio de Janeiro: DP&A; 2003. [ Links ]

. Mott ML, Byington MEB, Alves OSF. O gesto que salva: Pérola Byington e a Cruzada Pró-infância. São Paulo: Grifo Projetos Históricos e Editoriais; 2005. [ Links ]

. Pereira Neto AF. Ser médico no Brasil: o presente no passado. Rio de Janeiro: Editora Fiocruz; 2001. [ Links ]

. Rossister F. Guia prático de saúde. São Paulo: Casa Publicadora Brasileira; 1932. p.22-23. [ Links ]

16.  . Schraiber LB. O médico e seu trabalho: limites da liberdade. São Paulo: Hucitec; 1993 .Links ]

. Starr P. La transformación social de la Medicina en los Estados Unidos de América. México: Fondo de Cultura Económica; 1991. [ Links ]

. Stepan N. A hora da eugenia: raça, gênero e nação na América Latina. Rio de Janeiro: Editora da Fiocruz; 2005. [ Links ]

aAbreu HT. Os progressos da ciência e da igreja católica. Rio de Janeiro: Imprensa Médica; 1945. p.25-8.

bBourroul C. In: Anais do Primeiro Congresso de Médicos Católicos; 1946; Fortaleza, BR. São Paulo: Indústria Gráfica Siqueira; 1947. p.21.

cFontenelle JP. O trabalho de Saúde Pública no Brasil. 3o Congresso Brasileiro de Higiene; 1926 Nov 4-12; São Paulo, BR. São Paulo: Fiocruz; 1927.

dMoreira R. In: Anais do Primeiro Congresso de Médicos Católicos; 1946; Fortaleza, BR. São Paulo: Indústria Gráfica Siqueira; 1947. p.217.

eBechelli LM, Batista L. O problema da esterilização dos doentes de lepra. São Paulo; 1942. (Boletim de Higiene Mental, 5).

fPacheco e Silva AC. Discurso de abertura. In: Anais do Primeiro Congresso Brasileiro de Eugenia; 1929; Rio de Janeiro, BR. São Paulo: Academia Nacional de Medicina; 1929. p.1-2.

gPaula Souza GH. Os centros de saúde na organização sanitária do Estado de São Paulo. In: 3o Congresso Brasileiro de Hygiene; 1926 Nov 04 a 12, São Paulo, BR. São Paulo; 1927. p.59-86.

hAguiar EC. Os preventórios de São Paulo. Folha da Noite, 1936 5;5:2.

iBourroul C. Penitência e Medicina In: Anais do Primeiro Congresso de Médicos Católicos; 1946; Fortaleza, BR. São Paulo: Indústria Gráfica Siqueira; 1947.p.187-93

Received: April 10, 2013; Accepted: July 22, 2013

Correspondence : André Mota - Museu Professor Carlos da Silva Lacaz - Faculdade de Medicina – USP - Av. Dr. Arnaldo, 455 4º andar - 01246-903 São Paulo, SP, Brasil - E-mail:

This study was supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (Fapesp – Process no. 05/55509-9 to 2006-2008- Post-doctorate grant).

The authors declare that there are no conflicts of interest.

Creative Commons License This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License, which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.