Adherence to infliximab treatment in patients with immune-mediated inflammatory diseases from a referral center in Brazil: a cohort study.

BACKGROUND: Infliximab therapy is effective in controlling symptoms and attaining clinical remission of immune-mediated inflammatory diseases. However, treatment adherence is essential to achieve the therapeutic objective. This study aimed to determine the rate of adherence to infliximab treatment in patients treated at a referral center at a university hospital. METHOD: This ambispective cohort study included patients treated at the Professor Edgard Santos University Hospital (HUPES) referral center of our university hospital between March 2022 and February 2023. Sociodemographic, clinical, and pharmacotherapeutic data were collected from 101 patients through interviews and medical record reviews using a structured form. The adherence rate was defined as the proportion of days covered in a year. Patients who achieved an adherence rate > 80% were considered adherent. RESULTS: The treatment adherence rate was 91.04%. Individuals with inflammatory bowel diseases had a 39.1% higher risk of non-adherence to treatment compared with other patients in our sample (p < 0,05). Most patients achieved remission or control of the underlying disease activity and had good functional capacities. The main reason for absence on the scheduled date was difficulty traveling to the referral center. CONCLUSIONS: Despite the reported difficulties, treatment adherence was observed to be high. As the study was conducted in a reference unit with multidisciplinary care and continuous monitoring for treatment effectiveness, safety, and adherence, welcoming and good communication between professionals and patients may have contributed to the high adherence rate.

The impact of mental health and psychological stressors on menstrual cycle modulation: exploring the influence of age and hormonal contraceptives.

Stress, infections, and psychological and social well-being can affect the reproductive system. Activation of the hypothalamic-pituitary-adrenal axis can disrupt ovarian cyclicity. Estrogens can modulate stress responsiveness and mood. Thus, understanding this interaction and how it modulates the menstrual cycle is crucial for women's reproductive health. PURPOSE: The objective of this study was to analyze the influence of a stressor, a period of the Covid-19 pandemic when there were no vaccines available yet, on the psychological state of women aged 18 to 45 years; as well as the influence of mental health on the menstrual cycle, considering the influence of age and hormonal contraceptives. METHOD: Online questionnaire using the Google Forms platform was used. RESULTS: There is a high prevalence of the onset of new psychosocial symptoms. Moreover, most women reported some type of change in their menstrual cycles. The women who were using hormonal contraceptives demonstrated a higher frequency of spotting and menstrual color alterations, while women without hormonal contraceptives demonstrated a higher frequency of cycle duration and menstrual odor alterations. Women without hormonal contraceptives were more susceptible to the development of psychosocial symptoms. Younger adult women were more affected by menstrual changes and psychosocial symptoms. Close to 90% of women who reported several psychosocial symptoms had changes in their menstrual cycles. CONCLUSION: These data suggest the impact of stressors, such as a period of the pandemic, on mental health and menstrual cycles, and younger adult women can be more susceptible. This reflects the relationship between mental and reproductive health.

Trousseau syndrome preceding the diagnosis of colon cancer.

Trousseau Syndrome (TS) is defined as the occurrence of thromboembolic events prior to or simultaneously with the diagnosis of visceral neoplasia. In cases of multiple thromboembolisms, considering the possibility of TS, a screening for neoplasms may be warranted. We present a case study of a 61-year-old female who presented a neurological deficit. Brain magnetic resonance imaging (MRI) showed multiple hyperintense bihemispheric foci in subcortical and cortical regions involving three different vascular territories in the FLAIR sequence, associated with restricted diffusion inferring cytotoxic edema and indicating that they were all recent ischemic lesions, raising the hypothesis of TS. The patient underwent neoplastic screening with a subsequent diagnosis of colon cancer. TS should be considered when the patient presents thromboembolic events without an established cause. The three-territories-sign (TTS) is an essential radiographic biomarker related to cancer-associated ischemic stroke (CAIS). We propose that our findings be considered for the inclusion of guidelines that determine the investigation of an occult tumor (particularly gastric, pancreatic, lung, and colorectal) in patients who present thrombotic events, especially TTS.

Histopathologic and immunophenotypic profile of a spontaneous mammary carcinoma in a male Humboldt's white-fronted capuchin (Cebus albifrons).

A 20-year-old male captive Humboldt's white-fronted capuchin (Cebus albifrons) that died accidentally had a small non-ulcerative mammary nodule diagnosed as a mammary carcinoma. Immunohistochemistry demonstrated that neoplastic cells were positive for pan-cytokeratin and cytokeratin-7. Approximately 20% of neoplastic cells were positive for Ki-67. Neoplastic cells expressed estrogen and progesterone receptors.

Oral candidiasis in patients with haematological diseases: Diagnosis through clinical and cytopathological examinations.

OBJECTIVE: This study is the first to analyse the prevalence of oral candidiasis in onco-haematological patients by physical and oral cytopathological examinations. METHODS: This is a cross-sectional and observational study with a retrospective sample composed of participants hospitalised in the haematology clinic, who were diagnosed with haematological diseases. All participants received an oral mucosal examination and scraping from oral mucosa. RESULTS: Of the 62 participants, 56.5% were male and 82.3% were white, with mean age of 57 years. Lymphoma was the most common haematological disease (24.2%). In total, 48.4% of the sample was diagnosed with oral candidiasis. Of the participants with oral candidiasis, 13 (21.0%) had a clinical diagnosis. Cytopathological analysis revealed 17 more (27.4%) cases without oral lesions indicative of candidiasis. Erythematous candidiasis (P = 0.02), pseudomembranous candidiasis (P < 0.001), clinical candidiasis (P < 0.001), fibrous hyperplasia (P = 0.032), and coated tongue (P = 0.012) showed a correlation with a candidiasis cytopathological diagnosis. CONCLUSIONS: Oral candidiasis is common among patients with haematological disease, and the cytopathological examination proved to be a useful tool, confirming clinical diagnosis of candidiasis and identifying subclinical cases. These data are of great relevance considering the possible complications that these patients may develop, such as longer hospitalisations, worsening of the general condition or even death due to candidemia.

Characteristics and treatment of Brazilian pulp and paper mill effluents: a review.

Pulp and paper industries are very important for developing the Brazilian economy. During production processes, many effluents are generated with high polluting potential. The objective of this study is to conduct an extensive literature review on the characteristics of effluents and treatment forms adopted by Brazilian mills in this industrial sector. Most consulted studies address raw (without treatment) and secondary (after biological treatment) effluents, considering their main characteristics like pH, chemical and biochemical oxygen demands (COD and BOD, respectively), color, solids, organochlorines, toxicity, estrogenic activity, and phenols. Raw effluents differ considerably in composition, depending on the type of paper produced, the pulping process employed, and other steps, like pulp bleaching. Raw effluent characteristics indicate that this effluent cannot be directly disposed of into water bodies, because it does not comply with federal and state disposal standards. Secondary effluents normally comply with Brazilian legislations, although some studies have reported COD and total phenol concentrations higher than disposal standards, suggesting that additional treatments are necessary. Treated effluent reuse was verified in some Brazilian mills, while its disposal in eucalyptus plantations has been considered a promising alternative for irrigation purposes.

Epidemiological, clinical and pathological aspects of lethal acanthocephalosis in captive neotropical primates.

BACKGROUND: Acanthocephalosis is an important cause of death in captive New World primates (NWP). Once established in a colony, it is extremely difficult to treat and control, quickly spreading among NWP with a high mortality rate. This study aimed to characterize the disease associated with infection with acanthocephalans according to its epidemiological, clinical, and anatomopathological aspects in a captive NWP population. METHODS: From 2010 to 2020, a Brazilian zoo had recurrent deaths of NWP associated to acanthocephalan parasitism. Clinical and pathological profiles of these animals were analyzed considering the host species, sex, age, weight, clinical signs, therapeutic protocols, and pathological findings. RESULTS: A total of 27 deaths associated with acanthocephalosis were recorded, all lethal cases affected tamarins and lion tamarins, corresponding to 67.5% of total deaths during the course of this study. Ten animals died with no previously detected clinical signs, whereas cases with noticeable clinical signs often had apathy and progressive weight loss, resulting in cachexia. Symptomatic NWP were treated with anthelmintic protocols, antibiotics, and support therapy. However, all hospitalized animals died and had grossly detectable adult acanthocephalans in the intestinal lumen that were identified as Prosthenorchis sp., which were associated with transmural and ulcerative enteritis. CONCLUSIONS: This report revealed the impact of acanthocephalosis in a naturally infected captive colony of NWP, particularly affecting tamarins (Saguinus spp.) and lion tamarins (Leontopithecus spp.), with failed treatment and control strategies.

Isolation of 27 polymorphic nuclear microsatellite markers for Roupala montana var. brasiliensis (Proteaceae).

Microsatellite primers pairs were developed for the Neotropical tree Roupala montana var. brasiliensis for use in studies on genetic diversity, mating system, and gene flow. Forty-two primer pairs were developed, resulting in 27 polymorphic loci, with two to 27 alleles per locus. The primer pairs were validated against 34 R. montana var. brasiliensis adult trees from four populations. The observed (H o) and expected (H e)heterozygosities ranged among loci from 0.061 to 0.930 (mean of 0.544) and from 0.116 to 0.950 (mean of 0.700), respectively. Null alleles were observed for ten loci. No genotypic linkage disequilibrium was detected in any pair of loci. This set of loci is suitable for population genetic studies of the species.

ELOVL5 Participates in Embryonic Lipid Determination of Cellular Membranes and Cytoplasmic Droplets.

Embryonic lipids are crucial for the formation of cellular membranes and dynamically participate in metabolic pathways. Cells can synthesize simple fatty acids, and the elongation of fatty acids facilitates the formation of complex lipids. The aim of this work was to investigate the involvement of the elongation of very long chain fatty acid enzyme 5 (ELOVL5) in embryonic development and lipid determination. Bovine embryos were produced in vitro using a standard protocol and randomly divided to receive one of three treatments at Day 4: morpholino (Mo) gene expression knockdown assay for ELOVL5 (ELOVL5-Mo), Mo antisense oligonucleotides for the thalassemic ß-globulin human mRNA (technical control Mo), and placebo (biological control). The phenotypes of embryonic development, cell number, ELOVL5 protein abundance, lipid droplet deposits, and lipid fingerprint were investigated. No detrimental effects (p > 0.05) were observed on embryo development in terms of cleavage (59.4 ± 3.5%, 63.6 ± 4.1%, and 65.4 ± 2.2%), blastocyst production (31.3 ± 4.2%, 28.1 ± 4.9%, and 36.1 ± 2.1%), and blastocyst cell number (99.6 ± 7.7, 100.2 ± 6.2, 86.8 ± 5.6), respectively, for biological control, technical control Mo, and ELOVL5-Mo. ELOVL5 protein abundance and cytoplasmic lipid droplet deposition were increased (p < 0.05) in ELOVL5-Mo-derived blastocysts compared with the controls. However, seven lipid species, including phosphatidylcholines, phosphatidylethanolamines, and triacylglycerol, were downregulated in the ELOVL5-Mo-derived blastocysts compared with the biological control. Therefore, ELOVL5 is involved in the determination of embryonic lipid content and composition. Transient translational blockage of ELOVL5 reduced the expression of specific lipid species and promoted increased cytoplasmic lipid droplet deposition, but with no apparent deleterious effect on embryonic development and blastocyst cell number.

Gingival Biotype and Its Relationship With the Maxillary Membrane and Lateral Wall Thickness.

The purpose of this study was to analyze the risk of the maxillary sinus lift technique and the correlation between the thickness of the gingiva, maxillary sinus membrane, and the maxillary sinus lateral wall. Cone-beam computerized tomograhy (CBCT) records of 32 adult dentate patients (10 male/22 female) were analyzed. The gingival thickness records of the dental units were compared with the thickness measurements of the membrane and lateral wall of the maxillary sinus. The gingival biotypes varied between 1.1 mm (thin) and 1.6 mm (thick), with a small association with sex. The thickness of the sinus membrane presented a small association between sexes (0.2 mm, female/0.3 mm, male) and gingival biotypes (Cohen d = .52). The lateral wall presented a weak association between the biotypes (1.3 mm, thin/1.1 mm, thick). There was also no correlation between the membrane and lateral wall (r = -.22). The volume dimension related to the graft area of the sinus was 4 mm3 for men and 5 mm3 for women. There was a weak correlation of gingival thickness compared with membrane thickness and lateral wall of the sinus (r = .304/r = -.31). Gingival thickness does not appear to be a reliable thickness predictor of the membrane or lateral wall of the maxillary sinus. The analysis of maxillary sinus anatomical structures through CBCT is the most reliable technique to identify the thickness of the membrane and lateral wall of the maxillary sinus before surgery. We believe that new studies are necessary to confirm our findings.

Association between Scored Patient-Generated Subjective Global Assessment and Skeletal Muscle Determined by Computed Tomography in Patients with Cervical Cancer.

Introduction: Myopenia is a significant problem in oncology patients and the use of reliable instruments for its identification in clinical practice is necessary.Objective: To evaluate the association between the Scored Patient-Generated Subjective Global Assessment (PG-SGA) and skeletal muscle (SM) measured by computed tomography (CT) in patients with cervical cancer.Methods: This is an observational, cross-sectional study which enrolled women with cervical cancer, over 20 years, who started treatment between January 2015 and September 2018. The ones who presented PG-SGA and imaging of CT with a maximum interval of 45 days between them were included. The SM index (SMI) was used to classify myopenia and a significance level of 5% was adopted.Results: According to the PG-SGA, malnutrition was found in 56% patients and 23% were classified with myopenia by CT. The PG-SGA parameters were significantly associated with the SMI. The cutoff points that best discriminated myopenia were the PG-SGA total score ≥ 10, muscle depletion ≥ 2.0, and physical examination score ≥ 2.0.Conclusion: The PG-SGA showed to be a useful and viable method that shows good association and correlation with the SMI.

Poor sleep quality associates with self-reported psychiatric and cardiometabolic symptoms independently of sleep timing patterns in a large sample of rural and urban workers.

Poor sleep associates with mental and cardiometabolic pathological outcomes. The participation of sleep timing features in the pathways by which this relationship occurs is not clear. This study aims to evaluate the interrelationship between sleep quality and self-reported psychiatric/cardiometabolic symptoms, considering mediation and moderation effects of sleep timing patterns, and urban versus rural work environment, respectively; and to verify the association between sleep quality and polymorphisms of AANAT, RORA and TIMELESS genes. An epidemiological survey was performed in a rural area in southern Brazil. Eight-hundred and twenty-nine subjects were evaluated for sleep quality using the Pittsburgh Sleep Quality Index, and sleep timing patterns using the Munich Chronotype Questionnaire. Work characteristics and psychiatric/cardiometabolic symptoms were assessed using a structured self-report questionnaire. Three polymorphisms of AANAT, RORA and TIMELESS (rs3760138, rs782931 and rs774045, respectively) were genotyped in blood samples. We found statistically significant associations of poor sleep quality with self-reported psychiatric symptoms (B = 0.382; 95% CI 0.289-0.476; adjusted p-value <.001), and with self-reported cardiometabolic symptoms (B = 0.079; 95% CI 0.013-0.151; adjusted p-value = .048). The genetic analysis showed that RORA GA/AA genotype was associated to poor sleep quality (B = 0.146, 95% CI 0.054-0.239; adjusted p-value = .004). No moderated mediation effects were observed in the conditional analysis. TIMELESS polymorphism was not included in the analysis due to the low frequency of risk genotypes. These results yield new insights regarding the interrelationship between sleep characteristics and psychiatric/cardiometabolic self-reported symptoms, taking into account genes related to the biological clocks and melatonin pathways.

Prevalence of the NPHS2 variants p.R229Q, p.A242V, and p.R138Q in patients with focal segmental glomerulosclerosis.

BACKGROUND: NPHS2 gene variants are associated with focal segmental glomerulosclerosis (FSGS) and steroid-resistant nephrotic syndrome (SRNS). In this study, the prevalence of NPHS2 variants p.R229Q, p.A242V, and p.R138Q was investigated in patients with familial or sporadic FSGS. MATERIALS AND METHODS: The sample consisted of 40 children and 70 adults diagnosed with FSGS confirmed by renal biopsy. Clinical and laboratory parameters were evaluated. Genotyping for the three single nucleotide polymorphisms (SNPs) was performed by real-time polymerase chain reaction: two variants in exon 5 (p.R229Q and p.A242V) and one in exon 3 (p.R138Q). Variants were correlated with ethnicity, clinical presentation, treatment response, and renal outcomes. RESULTS: Among the 40 children analyzed, 20% had familial and 80% sporadic FSGS and among adults, 4.3% had familial and 95.7% sporadic FSGS, respectively. Overall, SRNS was found in 70% of adults and 90% in children. Among children, variants were detected in 2 (5%) with sporadic FSGS, p.R229Q and p.A242V in 1 each. Among adults, variants were present in 9 (12.9%) patients, all with sporadic FSGS, p.R229Q in 4 and p.A242V in 5. No patient had the p.R138Q variant. Among adults, a trend of higher proteinuria at the end of follow-up (p = 0.06) was found in patients carrying a variant. There was no significant association between NPHS2 variants with the clinical presentation, dependence on immunosuppressive treatment, or renal outcomes. Regarding ethnicity, all patients carrying the p.R229Q variant were White, while 67% of carriers of the p.A242V variant were Black. CONCLUSION: In these patients with familial or sporadic FSGS, the prevalence of p.R229Q and p.A242V variants in children was 5% and in adults 12.9%. More studies of patients with FSGS could better define a strategy for genetic analysis and therapeutic management.

Spirituality and quality of life in older adults: a path analysis model.

BACKGROUND: Study older adults' quality of life is becoming increasingly important in the assessment, quality improvement and allocation of health and social care service. The purpose of this study was to enhance knowledge on the relationship between modifiable (psychological variables) and non-modifiable variables (sociodemographic), and quality of life in elderly, regarding psychological and social variables in Portuguese context. METHODS: This is a cross-sectional study, including 604 older adults from general community. 63.6% of the sample was composed by female gender with a mean age of 71.6(SD = 4.81). Participants completed the following instruments: Barthel Index to assess functionality; Satisfaction with Social Support Scale to assess social support; The Spiritual and Religious Attitudes in Dealing with Illness to assess spirituality and Short Form Health Survey 36, to assess mental and physical quality of life. RESULTS: A path analysis model was performed where the presence of a chronic disease, age and functionality has a direct effect on physical quality of life and spirituality had a direct effect on mental quality of life. Social support mediated the relationship between functionality and mental quality of life, and in turn, functionality mediated the relationship between age and physical quality of life. CONCLUSIONS: Results reinforce the effect of age and chronic disease as non-modifiable variables as well as functionality, spirituality and satisfaction with social support as modifiable variables, in the quality of life of older people. Social support, health and education programs in the community should be promoted in order to improve quality of life in this population. Strategies to promote functionality and enhance the social support network, especially in the elder with chronic illness, should be a priority.

Treatment and characterization of biomass of soybean and rice hulls using ionic liquids for the liberation of fermentable sugars.

We investigated the changes in the physical structure of cellulose recovered from soybean and rice hulls treated with the ionic liquids 1-butyl-3-methylimidazolium chloride ([bmim][Cl]) and 1-butyl-3-methylimidazolium acetate ([bmim][Ac]). The characterization was carried out by a combination of thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). Regenerated cellulose from soybean hull showed loss of crystallinity and high structural disruption caused by both ionic liquid treatments as compared to the untreated material. In contrast, rice hull presented only a small structural disruption when treated with [bmim][Ac] and was practically unaffected by [bmim][Cl], showing that this biomass residue is recalcitrance towards physico-chemical treatments, possibly as a consequence of its high composition content in silica. These results suggest the use of soybean hull as a substrate to be treated with ionic liquids in the preparation of lignocellulosic hydrolysates to be used in second-generation ethanol production, whereas other methods should be considered to treat rice hull biomass.

DAO1 catalyzes temporal and tissue-specific oxidative inactivation of auxin in Arabidopsis thaliana.

Tight homeostatic regulation of the phytohormone auxin [indole-3-acetic acid (IAA)] is essential to plant growth. Auxin biosynthetic pathways and the processes that inactivate auxin by conjugation to amino acids and sugars have been thoroughly characterized. However, the enzyme that catalyzes oxidation of IAA to its primary catabolite 2-oxindole-3-acetic acid (oxIAA) remains uncharacterized. Here, we show that DIOXYGENASE FOR AUXIN OXIDATION 1 (DAO1) catalyzes formation of oxIAA in vitro and in vivo and that this mechanism regulates auxin homeostasis and plant growth. Null dao1-1 mutants contain 95% less oxIAA compared with wild type, and complementation of dao1 restores wild-type oxIAA levels, indicating that DAO1 is the primary IAA oxidase in seedlings. Furthermore, dao1 loss of function plants have altered morphology, including larger cotyledons, increased lateral root density, delayed sepal opening, elongated pistils, and reduced fertility in the primary inflorescence stem. These phenotypes are tightly correlated with DAO1 spatiotemporal expression patterns as shown by DAO1pro:ß-glucuronidase (GUS) activity and DAO1pro:YFP-DAO1 signals, and transformation with DAO1pro:YFP-DAO1 complemented the mutant phenotypes. The dominant dao1-2D mutant has increased oxIAA levels and decreased stature with shorter leaves and inflorescence stems, thus supporting DAO1 IAA oxidase function in vivo. A second isoform, DAO2, is very weakly expressed in seedling root apices. Together, these data confirm that IAA oxidation by DAO1 is the principal auxin catabolic process in Arabidopsis and that localized IAA oxidation plays a role in plant morphogenesis.

Item pre-knowledge true prevalence in clinical anatomy - application of gated item response theory model.

BACKGROUND: Computer and paper examinations in our days are constructed from an item pool which is regularly updated. Given the way that exams are created, one of the major concerns is the security of the items that are being used in order to ensure a good estimation of abilities. The aim of this study is to measure the prevalence of item pre-knowledge in our medical school. METHODS: The Deterministic, Gated Item Response Theory Model (DGM) was applied to estimate the prevalence of students who have had item pre-knowledge from six multiple choice examinations of the Clinical Anatomy course at the Faculty of Medicine of University of Porto. Each examination consisted of 100 items with an average of 200 students and 20% repeated items per examination. The estimation of the sensitivity and specificity was based on a simulation study. The sensitivity and specificity estimates, and apparent prevalence were used to estimate true prevalence of cheating students in the examinations under study. RESULTS: The specificity in the DGM for different simulation scenarios was between 68 and 98%, while the sensitivity ranged from 60 to 91%. The apparent prevalence was between 0.0 and 3.4%, while the true prevalence ranged from 1.2 to 3.7%. CONCLUSIONS: The true prevalence was much lower compared to the students self-reported copying of responses from other students; however, it is important to keep monitoring the pre-knowledge prevalence in order to enforce measures in case an increase occurs.

Investigating the existence of social networks in cheating behaviors in medical students.

BACKGROUND: Most studies on academic cheating rely on self-reported questionnaires and focus on the individual, overlooking cheating as a group activity. The aim of this study is to estimate the true prevalence of cheating/anomalies among medical students using a statistical index developed for this purpose, and to explore the existence of social networks between anomalies in students' results. METHODS: Angoff's A index was applied to a sample of 30 written examinations, with a total of 1487 students and 7403 examinations taken, from the 2014/2015 academic year of the Faculty of Medicine of the University of Porto to detect anomaly pairs. All analyses are within the same academic year and not across years. Through simulations, the sensitivity and specificity of the statistical method was determined, and the true prevalence of anomalies/cheating was estimated. Networks of anomaly pairs were created to search for patterns and to calculate their density. RESULTS: The percentage of students who cheated at least once increased with the year of medical school, being lowest in the first year (3.4%) and highest in the fifth (17.3%). The year of medical school was associated with anomalies (p < 0.05). The network's density was also lowest in the first year (1.12E-04) and highest in the fifth (8.20E-04). The true prevalence of anomalies was estimated to be 1.85% (95%CI: 1.07-3.20%). CONCLUSIONS: These findings suggest that some students are involved in social networks of cheating, which grow over time, resulting in an increase of anomalies/cheating in later academic years.

Effects of dietary microencapsulated Cymbopogon flexuosus essential oil on reproductive-related parameters in male Rhamdia quelen.

In aquaculture, nutrition and supplemented diets have been shown to affect broodstock reproductive performance. In this study, we investigated the effects of dietary supplementation with Cymbopogon flexuosus essential oil (CFEO) microcapsules on reproductive-related parameters in silver catfish (Rhamdia quelen) male broodfish. Adult male broodstocks were separated into three groups according to the concentrations of supplemented CFEO (0.0 = control; 1.0 or 3.0 mL per kg of diet). After 20 days under experimental conditions, the animals were euthanized and the gonads were harvested for gonadosomatic index, sperm analysis, oxidative stress, and histopathology; testosterone levels were measured in the plasma; gene expression of prl, smtl, pomca, and pomcb was assessed in the pituitary gland by real-time PCR. The results showed no alterations on reproductive parameters in R. quelen males treated with Cymbopogon flexuosus essential oil compared to the control-diet animals. In conclusion, CFEO microcapsules supplied for 20 days in the concentrations of 1.00 or 3.00 mL per kilogram of diet did not affect the reproduction criteria evaluated in this study in male silver catfish.