GDGiovana Dantas

Giovana Dantas

*This is an algorithmically generated author record based on publicly available information.

Giovana Dantas has a total of 78 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Laboratory validation of confirmatory tests for rabies diagnosis: Approaches to reduce animal use and facilitate sample collection

    by Bruno Egídio Cappelari, Fernanda Marques de Souza Godinho, Amanda Gonzalez da Silva, Adriana Almeida Belaguarda, Kenya Balz, Julio Cesar Almeida da Rosa, José Carlos Ferreira, Angélica Cavalheiro Bertagnolli, Paulo Michel Roehe, Helena Beatriz de Carvalho Ruthner Batista, et al.

    Rabies is an encephalitis caused by rabies virus, whose transmission occurs upon contact with infected animals' saliva. The diagnosis is usually performed post-mortem through a direct fluorescent antibody test (DFAT). If the DFAT results are negative, they must be confirmed with an isolation test, usually the mouse inoculation test (MIT), which implies the suffering and death of the animals, high costs and most importantly, up to 28 days to confirm a negative result. Another issue related to rabies diagnosis is the sample collection and storage, which is critical for the rabies virus' RNA genome. Thus, this study aimed to evaluate (i) reverse transcriptase polymerase chain reaction (RT-PCR) and Rabies Tissue Culture Infection Tests (RTCIT) in comparison to DFAT and MIT and (ii) FTA (R) cards as an alternative sample collection and preservation method. Eighty animal samples were evaluated through DFAT, RTCIT and RT-PCR; MIT was performed only in DFAT-negative samples. FTA (R) cards were evaluated with a subset of 64 samples, with sufficient material for imprinting. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV), agreement and Cohen's kappa were calculated for each test combination. RTC IT had higher sensitivity (92.5%) and RT-PCR had higher specificity (92.3%) compared to DFAT. The combination of tests enhanced sensitivity, NPV and Cohen's kappa (considering positive results by RTCIT or RT-PCR), and specificity and PPV (when both tests were concordant). The PCR based on FTA (R) cards as sample source was specific (84.6%-96.2%) but presented lower sensitivity (29.7%-73.0%), although it could detect as positive four DFAT-negative samples. RTC IT and RT-PCR may be used as confirmatory tests in DFAT-negative samples. Moreover, FTA (R) cards may be helpful for sample collection in field situations where a long time is needed until the sample undergoes laboratory testing.


  • Open Access

    Bovine rabies in Rio Grande do Sul: positivity rates, geographical distribution, and seasonal occurrence

    by Bruno Egídio Cappelari, Jéssica Grace da Silveira, Julio César de Almeida Rosa, José Carlos Ferreira, Giovana Dantas

    Rabies is a zoonotic disease characterized by acute viral encephalitis. It is almost 100% fatal for infected animals. While cases of human rabies have still been registered in Brazil, in the state of Rio Grande do Sul rabies is considered a controlled disease in urban areas. However, the transmission of bovine rabies – which has been largely associated with the Desmodus rotundus bat – is endemic. Additionally, there are estimates that only 10% of rabies cases are reported. Therefore, this study aimed to describe the positivity rates, geographical distribution, and seasonal occurrence of bovine rabies in RS, as well as the sampling practices in rabies surveillance. Using samples submitted for laboratory diagnosis from 2016 to 2019, we conducted a retrospective study of the sample results, positivity rates, and seasonal occurrence of rabies in cattle. Throughout these four years, less than a third of state municipalities sent samples for diagnosis, suggesting that the occurrence of rabies might still be underestimated in non-sampled areas. A higher number of rabies cases were reported in 2019, a year in which the most diagnosed samples and the highest positivity percentages were recorded. However, the case numbers registered between 2016 and 2019 were not significantly different. We found that the summer and autumn months presented statistically different positivity rates. Besides this, we did not find any positive D. rotundus samples, despite the positivity rates for bovine rabies. Active surveillance, especially of bat populations and under-sampled regions, must be strengthened to correctly estimate the impact of rabies.

  • Open Access

    Evaluation of the effects of acepromazine and xylazineon viability in an equine dermal cell line

    by Jéssica Grace da Silveira, Bruno Egídio Cappelari, Ana Paula Muterle Varela, Thais Fumaco Teixeira, Giovana Dantas de Araujo

    Xylazine and acepromazine are drugs used exclusively in veterinary medicine. Xylazineis used as a sedative, analgesic, and tranquilizer while acepromazine is used as a sedative, pre-anesthetic, and anesthetic adjuvant. In vitrodrug toxicity experimentation is essential to predict possible damage associated with treatment. This study was carried out to evaluate and compare the in vitroeffects of acepromazine and xylazine on cell viability. Equine Dermis cells lines were used to examine different drug concentrations (0.02 mg/mL, 0.01 mg/mL, 0.005 mg/mL and 0.0025 mg/mL). An MTT assay was carried out to reveal cell viability. Both tested drugs reduced the viability of ED cells at 0.02 and 0.01 mg/mL. At 0.005 mg/mL, only acepromazine presented an effect. These results corroborate previous studies with xylazine. On the other hand, this is thefirst report about acepromazine and cell viability. Previous studies suggest that the mechanisms involved in reducing cell viability are apoptosis for xylazine and the activation of the autophagic pathway for acepromazine. Both mechanisms have been seen in other drugs of the same classes. These findings reveal that both acepromazine and xylazine cause concentration-dependent cytotoxicity in vitro. Future experiments could further elucidate the mechanisms by which this effect happens and thus circumvent therisk of potential tissue damage in vivo.


  • Open Access

    Evaluation of data input in a rabies testing request form for herbivores

    by Victória Furtado Migliavacca, Michelle Elias Peres, José Carlos Ferreira, Júlio César de Almeida Rosa, Alexandre de Carvalho Braga, Laura Lopes de Almeida, Giovana Dantas de Araujo, Angélica Cavalheiro Bertagnolli

    Bovines and equines are the domestic animals with the highest incidence of rabies in Brazil. This study evaluated the data input in testing request forms for rabies in herbivores accompanying samples sent to a certified laboratory of rabies diagnosis in the state of Rio Grande do Sul, Brazil. Information was obtained systematically from all forms sent to the laboratory in 2013 and 2014 using a collection instrument that listed variables about the kind of form used, municipality of origin, description of the suspected animal, clinical signs, sample collection, and conservation procedure. The 11 most relevant variables (municipality of origin, geographic coordinates, species, gender, breed, age, herd size, clinical signs, persistence of clinical signs, biological material, and sample conservation) were assessed for the quality of the data entered, and percentage data input was calculated per form. In total, 603 forms were sent to the laboratory. The most used form was the FORM SN, (82.0%, 497/603). “Excellent” and “good” data inputs were observed only for one variable describing the location of suspected rabies cases or outbreaks and animals (species, gender, biological material). Quality of data input of variables describing geographic coordinates, age, breed, herd size, clinical signs, persistence of signs, and sample conservation method varied between “average” and “poor”. The data input in testing request forms for herbivores are not dully supplied in suspected cases neurological syndromes, pointing to the need to increase awareness and improve training of field staff.


  • Open Access

    Impacto do cronotipo na qualidade de vida de pacientes renais crônicos submetidos a tratamento hemodialítico

    by Angela Sartori, Paula Caitano Fontela, Giovana Dantas, Maria Leocadia Bernardes Amaral Padilha, Eliane Roseli Winkelmann

    Introdução: O cronotipo tem impacto para os desempenhos cognitivo e físico, o que pode influenciar na qualidade de vida (QV) dos pacientes com doença renal crônica (DRC).Objetivo: Avaliar o cronotipo dos pacientes com DRC em tratamento hemodialítico (THD) e analisar a QV de acordo com o cronotipo e o horário da hemodiálise.Materiais e Métodos: Estudo transversal, analítico e descritivo aprovado pelo Comitê de Ética em Pesquisa. Para caracterizar o cronotipo foi aplicado o Morningness-Eveningness Questionnaire (MEQ) e para avaliar a QV a Versão Brasileira do Questionário de Qualidade de Vida – SF36 e do Questionário para Pacientes Renais Crônicos – KDQOL-SF.Resultados: Foram incluídos 80 pacientes, 49 do sexo masculino, média de idade de 59,3±13,4 anos e tempo médio de THD de 27,5 meses. Quanto ao cronotipo, 68 (85%) foram classificados como matutinos, 12 (15%) como intermediários e nenhum vespertino. Observou-se redução significativa na QV dos pacientes com cronotipo intermediário no domínio capacidade funcional (p=0,05) do SF-36 e nos domínios efeitos da doença (p<0,01), apoio social (p=0,02) e função física (p=0,05) do KDQOL-SF. Constatou-se também, redução da QV no aspecto referente à composição física (p=0,05) do KDQOL-SF nos pacientes com cronotipo intermediário que realizavam hemodiálise às 07h00min comparado ao grupo das 10h30min.Conclusão: A maioria dos pacientes com DRC em THD tem seu cronotipo classificado como matutino. Os pacientes matutinos, quando comparados aos intermediários possuem melhor QV.


  • Open Access

    A new chronobiological approach to discriminate between acute and chronic depression using peripheral temperature, rest-activity, and light exposure parameters

    by Cláudia Ávila Moraes, Trinitat Cambras, Antoni Diez-Noguera, Regina Schimitt, Giovana Dantas, Rosa Levandovski, Maria Paz Hidalgo

    Background: Circadian theories for major depressive disorder have suggested that the rhythm of the circadian pacemaker is misaligned. Stable phase relationships between internal rhythms, such as temperature and rest/activity, and the external day-night cycle, are considered to be crucial for adapting to life in the external environmental. Therefore, the relationship and possible alterations among (i) light exposure, (ii) activity rhythm, and (iii) temperature rhythm could be important factors in clinical depression. This study aimed to investigate the rhythmic alterations in depression and evaluate the ability of chronobiological parameters to discriminate between healthy subjects and depressed patients. Methods: Thirty female subjects, including healthy subjects, depressed patients in the first episode, and major recurrent depression patients. Symptoms were assessed using Hamilton Depression Scale, Beck Depression Inventory and Montgomery-Äsberg Scale. Motor activity, temperature, and light values were determined for 7 days by actigraph, and circadian rhythms were calculated. Results: Depressed groups showed a lower amplitude in the circadian rhythm of activity and light exposure, but a higher amplitude in the rhythm of peripheral temperature. The correlation between temperature and activity values was different in the day and night among the control and depressed groups. For the same level of activity, depressed patients had lowest temperature values during the day. The amplitudes of temperature and activity were the highest discriminant parameters. Conclusions: These results indicate that the study of rhythms is useful for diagnosis and therapy for depressive mood disorders.


  • Open Access

    Impact of the time in an animal model of mood disorder

    by Etianne Martini Sasso, Juliana Luiza Vieira, Giovana Dantas, Camila Morelatto de Souza, Rosa Maria Levandovski, Maria Paz Loayza Hidalgo


  • Depression Scores Associate With Chronotype and Social Jetlag in a Rural Population

    by Rosa Levandovski, Giovana Dantas, Luciana Carvalho Fernandes, Wolnei Caumo, Iraci Torres, Till Roenneberg, Maria Paz Loayza Hidalgo, Karla Viviani Allebrandt

    In public health, mood disorders are among the most important mental impairments. Patients with depressive episodes exhibit daily mood variations, abnormal patterns in sleep-wake behavior, and in the daily rhythms of several endocrine-metabolic parameters. Although the relationship between the sleep/circadian processes and mood disorders is poorly understood, clock-related therapies, such as light therapy, sleep deprivation, and rigid sleep schedules, have been shown to be effective treatments. Several studies investigated the relationship between circadian phenotype (chronotype) and depression. These focused mainly on urban populations and assessed diurnal preferences (Morningness-Eveningness score) rather than the actual timing of sleep and activity. Here, we used the Beck Depression Inventory (BDI) in an essentially rural population (N = 4051), and investigated its relation to circadian phenotype (chronotype and social jetlag), assessed with the Munich Chronotype Questionnaire (MCTQ). In our study design, we (i) normalized both chronotype and BDI scores for age and sex (MSFsas and BDIas, respectively); (ii) calculated individual social jetlag (misalignment of the biological and social time); and (iii) investigated the relationship between circadian phenotypes and BDI scores in a population homogeneous in respect to culture, socioeconomic factors, and daily light exposure. A 15.65% (N = 634) of the participants showed mild to severe depressive BDI scores. Late chronotypes had a higher BDIas than intermediate and early types, which was independent of whether or not the participants were smokers. Both chronotype and BDIas correlated positively with social jetlag. BDIas was significantly higher in subjects with >2 h of social jetlag than in the rest of the population—again independent of smoking status. We also compared chronotype and social jetlag distributions between BDI categories (no symptoms, minimal symptoms, and mild to severe symptoms of depression) separately for men and women and for four age groups; specifically in the age group 31–40 yrs, subjects with mild to severe BDI scores were significantly later chronotypes and suffered from higher social jetlag. Our results indicate that misalignment of circadian and social time may be a risk factor for developing depression, especially in 31- to 40-yr-olds. These relationships should be further investigated in longitudinal studies to reveal if reduction of social jetlag should be part of prevention strategies. (Author correspondence: karla. allebrandt@med. uni-muenchen. de )


  • 6‐Sulfatoxymelatonin as a predictor of clinical outcome in depressive patients

    by Maria Paz Loayza Hidalgo, Wolnei Caumo, Giovana Dantas, Daiane Gil Franco, Iraci Lucena da Silva Torres, Julio Pezzi, Elaine Elisabetsky, Bernardo Carraro Detanico, Ângelo Piato, Regina P. Markus

    Objectives: This study established the value of the 6‐sulfatoxymelatonin (aMT6s) urine concentration as a predictor of the therapeutic response to noradrenaline reuptake inhibitors in depressive patients.Methods: Twenty‐two women aged 18–60 years were selected. Depressive symptoms were assessed by using the Hamilton Depression Scale. Urine samples were collected at 0600–1200 h, 1200–1800 h, 1800–2400 h, and 2400–0600 h intervals, 1 day before and 1 day after starting on the nortriptyline treatment. Urine aMT6s concentration was analyzed by a one‐way analysis of variance/Bonferroni test. Spearman's rank correlation coefficient was used to analyze the correlation between depressive symptoms after 2 weeks of antidepressant treatment and the increase in aMT6s urine concentration.Results: Higher and lower size effect groups were compared by independent Student'st‐tests. At baseline, the 2400‐ to 0600‐h interval differed from all other intervals presenting a significantly higher aMT6s urine concentration. A significant difference in aMT6s urine concentrations was found 1 day after treatment in all four intervals. Higher size effect group had lower levels of depressive symptoms 2 weeks after the treatment. A positive correlation between depressive symptoms and the delta of aMT6s in the 2400–06 00h interval was observed.Conclusion: Our results reinforce the hypothesis that aMT6s excretion is a predictor of clinical outcome in depression, especially in regard tonoradrenaline reuptake inhibitors. Copyright © 2011 John Wiley & Sons, Ltd.


  • Morningness–eveningness, use of stimulants, and minor psychiatric disorders among undergraduate students

    by Márcia Lacerda De Medeiros Schneider, Denise Camargo Vasconcellos, Giovana Dantas, Rosa Levandovski, Wolnei Caumo, Karla V. Allebrandt, Marlene Doring, Maria Paz Loayza Hidalgo

    Morningness–eveningness dimension in humans have been indicated to influence social behavior and individual health. The aim of the present study was to investigate the association of the morningness–eveningness dimension with behavioral and health aspects in a sample of undergraduate students. We assessed demographic data; the Pittsburgh Sleep Quality Index was used to evaluate sleep quality; the Morningness/Eveningness Questionnaire to determine morningness–eveningness, and the Self‐Reporting Questionnaire to assess minor psychiatric disorders. A total of 372 students (66.7% females), on average 21.6 years old, participated in this study. Among them, 92.2% did not smoke, 58.9% engaged in physical activities, and 19.7% were night‐shift workers. In regard to morningness–eveningness, 55.9% of the participants were intermediate between evening (39.5%) and morning (4.6%) types. Poor sleep quality (OR = 1.89), minor psychiatric disorders (OR = 1.92), and tobacco consumption (OR = 3.65) predominated among evening types. Evening types were predominantly males (OR = 1.72). This study suggests that evening types are more vulnerable to sleep and psychiatric disturbances, and tend to smoke more than morning types.