Time variation of some selected topics in bioethical publications

OBJECTIVE

To analyse the time variation of topics in bioethical publications as a proxy of the relative importance.

METHODS

We searched the Medline database for bioethics publications using the words "ethics or bioethics", and for 360 specific topics publications, associating Medical Subject Heading topic descriptors to those words. We calculated the ratio of bioethics publications to the total publications of Medline, and the ratio of each topic publications to the total bioethics publications, for five-year intervals, from 1970 to 2004. We calculated the time variation of ratios, dividing the difference between the highest and lowest ratio of each topic by its highest ratio. Four topics were described, selected to illustrate different patterns of variation: "Induced Abortion", "Conflict of Interest", "Acquired Immunodeficiency Syndrome", "Medical Education."

RESULTS

The ratio of bioethics publications to total Medline publications increased from 0.003 to 0.012. The variation of the topic's ratios was higher than 0.7 for 68% of the topics. The Induced Abortion ratios decreased from 0.12 to 0.02. Conflict of Interest ratios increased from zero to 0.07. The Acquired Immunodeficiency Syndrome ratios were nearly zero in the first three intervals, had a peak of 0.06 during 1985-9, followed by a decrease to 0.01. Medical Education ratios varied few, from 0.04 to 0.03.

CONCLUSIONS

There was an increase of bioethical publications in the Medline database. The topics in bioethics literature have an important time variation. Some factors were suggested to explain this variation: current legal cases, resolution of the issue, saturation of a discussion and epidemiologic importance.

Fuzzy Decision Making in Public Health Strategies

Making decision is one of the most fundamental activities of human beings (Klir & Yuan, 1995; Yager & Filev, 1994; Zadeh, 1973). This is particularly true in Public Health where decisions usually have relevance for millions of people. In the field of vaccination strategies design, decision making concerning the target population for the immunization program, the proportion of susceptibles to be vaccinated, the optimal age to immunize children and the nature of the strategy, e.g. selective or indiscriminate, are examples of the variables to be optimized, subject to a set of constraints. As an example, we present in this chapter a fuzzy model to decision making applied to the design of the vaccination campaign against measles in São Paulo, Brazil (Massad et al., 1999)

Estudo de comportamento associado à infecção pelo HIV e HCV em detentas de um presídio de São Paulo, Brasil

Observa-se aumento do número de casos de AIDS e hepatite C entre mulheres, incluindo aquelas confinadas no sistema prisional. Este trabalho propôs estudar aspectos relacionados ao comportamento sexual e associados ao risco de transmissão do HIV e da hepatite C em detentas numa penitenciária de São Paulo, Brasil. É um estudo transversal realizado em 2000, aplicando questionários de comportamento e obtendo diagnósticos sorológicos para HIV e HCV. A medida de associação escolhida foi OR para análises bi e multivariada (regressão logística). Participaram do estudo 290 detentas. A prevalência observada para HIV e HCV foi de 13,9% e 16,2%, respectivamente. Associações estatisticamente significantes (p < 0,05) para HIV positivo foram observadas para as variáveis: parceiros com AIDS OR = 6,9 (2,7-35,2); usuários de drogas ingetáveis (UDI) OR = 3,3 (1,6-14,7); parceiro fixo OR=3,7 (1,5-8,3) e para HCV positivo com UDI OR = 13,7 (4,4-42,7); parceiro UDI OR = 4,9 (1,9-12,2); prisão anterior OR = 2,8 (1,2-6,5) ajustadas por: parceiros com AIDS, UDI, parceiro UDI, uso de drogas e prisão anterior. Concluiu-se que o risco parenteral foi associado com infecções pelo HIV e HCV, e o sexual, pelo HIV. Recomendam-se programas de prevenção adequados e continuados no ambiente carcerário.

The 1918 influenza A epidemic in the city of São Paulo, Brazil

The 1918 pandemic H1N1 outbreak in the city of São Paulo is revisited. The outbreak lasted for 10 weeks and reached 116,771 officially recorded cases amongst 523,194 inhabitants. The total number of deaths summed up to 5331, with a lethality rate of 4.5% and an overall mortality rate of around 1%. We propose a mathematical model that tallies available data with good accuracy and allows the estimation of the basic reproductive number, R(0). The model showed a remarkably good accuracy in retrieving the real data from São Paulo city outbreak considering the total number of recorded cases and deaths and the timing of the outbreak. The basic reproduction number calculated of 2.68 can be compared to estimates carried out for other flu strains, like the estimates for H3N2, whose values ranged from 1.5 to 2.5. We hypothesize that the Southern parts of the world in which there was relatively little impact of the Great War, like South America, suffered a much lower H1N1 influenza mortality as compared with that reported for the Northern hemisphere heavily affected by the I World War.

Threshold conditions for a non-autonomous epidemic system describing the population dynamics of dengue

A non-autonomous dynamical system, in which the seasonal variation of a mosquito vector population is modeled, is proposed to investigate dengue overwintering. A time-dependent threshold, R(t), is deduced such that when its yearly average, denoted by R, is less than 1, the disease does not invade the populations and when R is greater than 1 it does. By not invading the population we mean that the number of infected individuals always decrease in subsequent seasons of transmission. Using the same threshold, all the qualitative features of the resulting epidemic can be understood. Our model suggests that trans-ovarial infection in the mosquitoes facilitates dengue overwintering. We also explain the delay between the peak in the mosquitoes population and the peak in dengue cases.

Mental retadation: a MRI study of 146 Brazilian children

We report results of a magnetic ressonance imaging (MRI) study of 146 Brazilian children, whose intelligence quotient scored less than 70. 50% of MRI examinations did not exhibit any signal of structural lesion (N group), whereas a focal thinning at the junction of the body and splenium of the corpus callosum; ventricular asymmetry; periventricular leukomalacia; gliosis and arachnoid cysts were among the most frequent findings in the remaining of subjects (L group). Maternal stress and altered blood pressure were the most frequent findings in the pre-natal history of both N and L children. Familial antecedents of mental deficiency were reported in 30% of both groups, whereas familiar history of alcoholism was important in N group (60% in N versus 0% in L groups). Neuropsychomotor development was delayed in 80% of the children in both groups. Aggressiveness is the most frequent finding in the post-natal children history.

A certificate program in health informatics: Brazil/USA experience

Considering the continued demand for a large number of trained professionals we decided to offer a certificate program in health informatics. The objective is to prepare professionals to conduct research and implement the curriculum content in their original institutions. We selected 14 candidates from several national institutes. The disciplines are taught by Brazilian and US faculty. Researches conducted by the certificate students were relevant to Brazil's health needs. The goal is to promote better health informatics education, regardless of geographic distribution of students.

The impact of imperfect vaccines on the evolution of HIV virulence

A theoretical framework is proposed on which some hypotheses related to the impact of imperfect vaccines on the evolution of HIV virulence can be tested. For this, a linear increase of risk behaviour with vaccine efficacy is assumed. This is based on the hypothesis that people are prone to relax preventive measures by knowing that they and their partners are vaccinated and that this effect is more intense the more effective the vaccine is known to be. An additional, and perhaps more important hypothesis is related to the theoretical possibility that increased risk behaviour of some vaccinated individuals in partially protected populations could act as a selective pressure toward more virulent HIV strains. Those hypotheses were tested by a mathematical model that considers three different HIV strains competing against each other in a population partially protected by imperfect vaccines of distinct efficacies. Simulations of the model demonstrated that, under the above hypotheses, there is a shift in HIV virulence towards more aggressive strains with increase in vaccine efficacy, associated with a marked reduction in the total amount of transmission and, consequently, in the prevalence of HIV. Potential ways for further testing the theory/model and the implications of the results are discussed.

Fuzzy logic model based on the differential nursing diagnosis of alterations in urinary elimination

The nursing diagnoses associated with alterations in urinary elimination require different interventions, and nurses who are not specialists need support to diagnose and to manage patients with disturbances of urine elimination. The aim of this study was to present a model based on fuzzy logic for making differential diagnosis of alterations in urinary elimination, considering the nursing diagnosis approved by the North American Nursing Diagnosis Association (NANDA), 2001-2002. The fuzzy maximum-minimum composition was used to develop this model. It was tested with 195 cases from a database of a previous study. The model was able to determine the diagnosis in total accordance with a panel of three experts for 79.5% of the cases. The model diagnosed 19% of the cases with partial concordance with the panel of experts. Only for 3 cases (1.5%) the model showed a different diagnosis. It is concluded that the model proposed here, despite of its simplicity, presents good performance. However, it is recommended more tests before widely used as support for clinical decision.

Liver Transplantation: Waiting List Dynamics in the State of São Paulo, Brazil

São Paulo is the first Brazilian state to perform liver transplantation in 1968. Since then the recipient waiting list has increased; now approximately 150 new cases per month are referred to the single list at the central organ procurement organization. Official data have shown 37.3 monthly deaths on the waiting list in the state of São Paulo. The number of liver transplants has increased after the creation of São Paulo transplant notification centers but are insufficient to deal with the increasing waiting list. The aim of this study was to demonstrate the performance of our state liver transplantation program and analyze when the number of liver transplantations will meet our waiting list demand.

Age-specific seroprevalence to an immunodominant Cryptosporidium sporozoite antigen in a Brazilian population

The seroepidemiology of Cryptosporidium infection was investigated in a representative sample of a normal population in the State of Sao Paulo, Brazil using a recombinant form of the immunodominant 27-kDa sporozoite antigen. IgG seropositivity was low in infants following loss of maternal antibody but quickly increased to approximately 60% by 5 years, then 80% by the age of 10 years, after which prevalence remained constant. The broad range of antibody concentrations is consistent with previous reports that the IgG response to C. parvum is short-lived. There is also evidence that average antibody concentrations increase with age. Results suggest that the recombinant antigen may be a more sensitive method of measuring seroprevalence than the native antigen in Western blot. Although cross-sectional studies can provide an insight into the epidemiology of C. parvum in normal populations, further studies investigating the dynamics of the humoral immune responses to Cryptosporidium and the use of serology in epidemiological studies are required.

Tendências da vulnerabilidade às infecções pelo HIV e HCV entre internos da FEBEM avaliados em diferentes períodos - 1994 a 1995 e 2000 a 2001

<span style="font-family: Helvetica; font-size: xx-small;"><span style="font-family: Helvetica; font-size: xx-small;"><p>Este estudo faz uma abordagem da condição do menor infrator, internos da FEBEM (Fundação Estadual para o Bem Estar do Menor de São Paulo) e sua situação de risco sob diferentes prismas. Apóia-se em dois estudos homogêneos desenvolvidos em momentos diferentes, onde avaliam a vulnerabilidade do menor infrator à infecção pelo HIV e HCV, nos períodos de 1994 a 1995 e 2000 a 2001.</p></span></span>

Indirect oral immunization of captive vampires, Desmodus rotundus

A vaccinia-rabies glycoprotein recombinant virus (V-RG) vaccine was tested in hematophagous bats (Desmodus rotundus) kept in captivity. The vaccine was applied in a neutral vehicle (Vaseline) spread on the back of one or two vector bats, which were then reintroduced into their groups. Our hypothesis was that, as in the case of vampire bat control by vampiricide paste, the administration of V-RG vaccine through paste to one bat could indirectly protect other bats from the same group. Eight groups were tested. The rabies virus strain used to challenge the bats was isolated from a naturally infected hematophagous bat (Desmodus rotundus). The survival proportion after the virus challenge ranged between 42.8 and 71.4%. The results are encouraging because a significant number of bats that did not receive the vaccine survived the challenge. The vaccine was shown to be safe and immunogenic to hematophagous bats. No adverse effects to vaccinia virus were observed.

Experimental rabies infection in haematophagous bats Desmodus rotundus

In order to determine the susceptibility and serum neutralizing antibody response of Desmodus rotundus to rabies virus, bats were inoculated with a virus isolated from a naturally infected haematophagous bat. Bats were divided into four groups of 10 animals each. Dilutions of rabies virus containing 100, 1000, 10,000 and 100,000 MICLD50 (lethal dose 50% for mice inoculated by the intracerebral route) were administrated in the pectoral muscle. The presence of rabies virus was detected in brain and salivary glands by fluorescent antibody, mouse inoculation and RT-PCR. The observed mortality for each virus dose was 0, 20, 20 and 60% respectively. Serum neutralizing antibodies were tested for by the rapid fluorescent focus inhibition test, and antibody titres greater than 0.5 IU/ml were found in 53% of bats 30 days after virus inoculation. Resistance to infection was seen in bats that developed low or no detectable antibody response as well as in bats with high titres. Among the 10 bats that died of rabies, eight showed signs of paralytic rabies and two bats showed no clinical signs.

Yellow fever vaccination: How much is enough?

In recent years, a growing number of serious adverse events (including deaths) associated with the yellow fever (YF) vaccine has been reported. If YF vaccination were incorporated in routine programs, administered to children, the risk of deaths from this vaccine would be minimized provided that mortality of children vaccinated below 1 year were negligible. However, in affected areas the vaccine is administered to all age groups. This poses a dilemma to public health authorities - what proportion of a population subject to low risk of YF outbreaks should be vaccinated in order to minimize the total number of serious adverse events (including deaths) due both to natural infection and vaccination? In other words, how much vaccination is safe? Our results suggest that, depending on the age-specific rates of developing vaccine-induced serious adverse events and the risk of yellow fever outbreaks, the optimum proportion to vaccinate may be lower than the proportion that would prevent an epidemics or even be zero. We also show that the vaccine should not be applied to individuals older than 60 years of age because the risk of serious adverse events (including deaths) is higher for that age class. Our work is instrumental to the discussion on the optimum strategy to vaccinate affected populations against yellow fever. Therefore, the aim of this work is to estimate the optimum proportion to vaccinate against YF taking into account the risks of serious adverse events associated with both the vaccine and natural infection.

The Eyam plague revisited: did the village isolation change transmission from fleas to pulmonary?

Back in the 17th century the Derbyshire village of Eyam fell victim to the Black Death, which is thought to have arrived from London in some old clothes brought by a travelling tailor. The village population was 350 at the commencement of plague, of which only 83 survived. Led by the church leaders, the village community realized that the whole surrounding region was at risk from the epidemic, and therefore decided to seal themselves off from the other surrounding villages. In the first 275 days of the outbreak, transmission was predominantly from infected fleas to susceptible humans. From then onward, mortality sharply increased, which indicates a changing in transmission pattern. We hypothesize that the confinement facilitated the spread of the infection by increasing the contact rate through direct transmission among humans. This would be more consistent with pulmonary plague, a deadlier form of the disease. In order to test the above hypothesis we designed a mathematical model for plague dynamics, incorporating both the indirect (fleas-rats-humans) and direct (human-to-human) transmissions of the infection. Our results show remarkable agreement between data and the model, lending support to our hypotheses. The Eyam plague episode is celebrated as a remarkable act of collective self-sacrifice. However, to the best of our knowledge, there were no evidence before that the confinement actually increased the burden payed by the commoners. In the light of our results, it can be said that the hypothesis that confinement facilitated the spread of the infection by increasing the contact rate through direct transmission is plausible.

Brain mappings of the arithmetic processing in children and adults

Despite the increasing number of experimental mapping showing that human arithmetic cognition is supported by widely spread neural circuits; the theoretical reasoning about these data remains mostly metaphorical and guided by a connectionist approach. Although neurons at distinct areas in the brain are assumed to take charge of different duties in the solution of the experimental task, the results are always discussed by hypothesizing some association between the different areas without questioning any difference of behavior at the level of the neurons at each of these areas. Here, the brain is assumed as Distributed Intelligent Processing System (DIPS) formed by collections of loosely interacting specialized agents (neurons), each agent specializing, for example, in data collection (sensors), problem solving (associative neurons), data communication (interneuronal systems) and in acting upon the surrounding environment (motorneurons). A new technique for EEG brain mapping is proposed and used to study arithmetic cognition in elementary school aged children and adults. Factor analysis showed three distinct patterns of neuronal recruitment for arithmetic calculations in all experimental groups which varied according to the type of calculation, age and sex.

Training health informatics professionals in Brazil: rationale for the development of a new certificate program

Current graduate degree programs in Brazil cannot fulfill the demand for highly trained health informatics practitioners. We have developed an intensive six-month program to train 20 students per year. They will receive partial subsidy from our bilateral training program and receive the title of Specialist in Health Informatics. They will benefit from a curriculum involving coursework and collaborative research designed by Brazilian and US-based faculty.

Forecasting versus projection models in epidemiology: the case of the SARS epidemics

In this work we propose a simple mathematical model for the analysis of the impact of control measures against an emerging infection, namely, the severe acute respiratory syndrome (SARS). The model provides a testable hypothesis by considering a dynamical equation for the contact parameter, which drops exponentially with time, simulating control measures. We discuss the role of modelling in public health and we analyse the distinction between forecasting and projection models as assessing tools for the estimation of the impact of intervention strategies. The model is applied to the communities of Hong Kong and Toronto (Canada) and it mimics those epidemics with fairly good accuracy. The estimated values for the basic reproduction number, R0, were 1.2 for Hong Kong and 1.32 for Toronto (Canada). The model projects that, in the absence of control, the final number of cases would be 320,000 in Hong Kong and 36,900 in Toronto (Canada). In contrast, with control measures, which reduce the contact rate to about 25% of its initial value, the expected final number of cases is reduced to 1778 in Hong Kong and 226 in Toronto (Canada). Although SARS can be a devastating infection, early recognition, prompt isolation, and appropriate precaution measures, can be very effective to limit its spread.