Gender-Based Discrimination Among Medical Students: A Cross-Sectional Study in Brazil.

INTRODUCTION: Gender-based discrimination (GBD) creates a hostile environment during medical school, affecting students' personal life and academic performance. Little is known about how GBD affects the over 204,000 medical students in Brazil. This study aims to explore the patterns of GBD experienced by medical students in Brazil. METHODS: This is a cross-sectional study using an anonymous, Portuguese survey disseminated in June 2021 among Brazilian medical students. The survey was composed of 24 questions to collect data on GBD during medical school, formal methods for reporting GBD, and possible solutions for GBD. RESULTS: Of 953 responses, 748 (78%) were cisgender women, 194 (20%) were cisgender men, and 11 (1%) were from gender minorities. 65% (616/942) of respondents reported experiencing GBD during medical school. Women students experienced GBD more than men (77% versus 22%; P < 0.001). On comparing GBD perpetrator roles, both women (82%, 470/574) and men (64%, 27/42) reported the highest rate of GBD by faculty members. The occurrence of GBD by location differed between women and men. Only 12% (115/953) of respondents reported knowing their institution had a reporting mechanism for GBD. CONCLUSIONS: Most respondents experienced GBD during medical school. Cisgender women experienced GBD more than cisgender men. Perpetrators and location of GBD differed for men and women. Finally, an alarming majority of students did not know how to formally report GBD in their schools. It is imperative to adopt broad policy changes to diminish the rate of GBD and its a consequential burden on medical students.

Gender Discrimination, Career Aspirations, and Access to Mentorship Among Medical Students in Brazil.

INTRODUCTION: Gender-based discrimination (GBD) creates a hostile environment that can affect medical students. Mentorship has been recognized as a mitigating factor for GBD. We aimed to investigate the impacts of GBD on career selection and well-being of medical students in Brazil and to explore access to mentorship among these students. METHODS: A cross-sectional study was performed using an anonymous survey in Portuguese. The survey was distributed in June 2021 to students enrolled in Brazilian medical schools. It contained 24 questions, including demographics, episodes of GBD experienced by responders and their impact on professional and personal life, and mentorship access. RESULTS: Of 953 respondents, 748 (78%) were cisgender women, 194 (20%) cisgender men, and 11 nonbinary (1%). Sixty-six percent (625/953) of students reported experiencing GBD, with cisgender women and nonbinary being more likely to experience it than cisgender men (P < 0.001). Responders who experiences GBD report moderate to severe impact on career satisfaction (40%, 250/624), safety (68%, 427/624), self-confidence (68%, 426/624), well-being (57%, 357/625), and burnout (62%, 389/625). Cisgender women were more likely to report these effects than men counterparts (P < 0.01). Only 21% of respondents (201/953) had mentors in their medical schools. CONCLUSIONS: Our findings demonstrate that GBD is widespread among Brazilian medical students affecting their personal and professional lives, and most of them do not have access to a mentor. There is an urgent need to increase access to mentors who could mitigate the adverse effects of GBD and help develop a diverse and inclusive medical workforce.

Magnetic Hybrid Wax Nanocomposites as Externally Controlled Theranostic Vehicles: High MRI Enhancement and Synergistic Magnetically Assisted Thermo/Chemo Therapy.

To fight against cancer, smarter drugs and drug delivery systems are required both to boost the efficiency of current treatments while reducing deleterious side effects, and combine diagnosis/monitoring with therapy (theranosis) in the search for the final goal of personalized medicine. This work presents the design, preparation, and proof-of-principle validation of a novel hybrid organic-inorganic nanocomposite joining together non-invasive imaging capabilities through magnetic resonance imaging and externally actuated therapeutic properties through a combination of chemo- and thermotherapy. The lipidic matrix of the nanocomposite was composed of carnauba wax, which was simultaneously dual loaded with magnetite nanoparticles and the anticancer drug Oncocalyxone A. Obtained formulations were fully characterized and showed outstanding performances as T2 -contrast agents in magnetic resonance imaging (r2 >800 mm-1 s-1 ), heat generating sources in magnetic hyperthermia (specific absorption rate, SAR>200 W g-1 Fe ), and magnetically responsive drug delivery vehicles. The potential of the designed formulations as theranostic agents was validated in vitro and results indicated a synergistic thermo/chemotherapeutic effect derived from heat generation and controlled drug delivery to cancer growth. Thereby, this external control over the drug delivery profile and the integrated imaging capability open the door to personalized cancer medicine and real-time monitoring of tumor progression.

Are food compounds able to modulate noxious activities induced by cadmium exposure?

Cadmium is one of the most toxic environmental and industrial pollutants and is able to induce severe injury because it is poorly excreted, accumulating in various organs. This common pollutant is responsible for serious damage in lung, brain, testis, kidney, liver, circulatory system, and bone. Food compounds, such as flavonoids, represent the most abundant polyphenols in human diet and comprise thousands of substances, which are freely available as high-dose dietary supplements. The mechanism of action of these ones consists in free radical scavenging and metal sequestration. The interaction of metal ions with flavonoids leads to chelation and the use of these natural compounds is better than the synthetic ones due to their lower toxic effects. The aim of this review is to describe the role of some food compounds, focusing on flavonoids for modulating noxious biological activities induced by cadmium exposure.

Anti-tumor activity of grape juice concentrate in the rat tongue two-stage initiation-promotion protocol induced by 4-nitroquinoline 1-oxide.

The aim of this study was to evaluate the anti-tumor activity of grape juice concentrate following medium-term oral carcinogenesis assay induced by 4-nitroquinoline 1-oxide (4NQO). A total of 30 male Wistar rats were distributed into five groups, as follows (n = 6 per group): Group 1 - negative control group (non-treated group); Group 2 - received grape juice concentrate at 1% dose by gavage for eight consecutive weeks; Group 3 - received 4NQO for 8 weeks at 20 ppm dose in drinking water daily; Group 4 - received 4NQO at 20 ppm dose during 8 weeks in drinking water and treated with grape juice concentrate at 1% dose orally by gavage for first 4 weeks after 4-NQO administration; Group 5 - received 4NQO at 20 ppm dose for 8 weeks in drinking water and treated with grape juice concentrate at 1% dose orally by gavage between the 5th and 8th weeks daily. Histopathological analysis revealed a decrease in hyperplasic and dysplastic lesions in Group 4. Groups 4 and 5 showed decreased COX-2 and TNF-alpha and eNOS gene expression. Grape juice concentrate also increased SOD Cu/Zn and catalase expression. However, Ki-67 immunoexpression was reduced at the promotion step of oral carcinogenesis (G5). Taken together, our results demonstrate that grape juice concentrate modulates rat tongue carcinogenesis as a result of anti-inflammatory activity, antioxidant activity and down-regulation of oral cells proliferation.

Mimosa (Mimosa caesalpiniifolia) prevents oxidative DNA damage induced by cadmium exposure in Wistar rats.

The Mimosa (Mimosa caesalpiniifolia) is a plant native from South America; it is used in the traditional medicine systems for treating bacterial, fungal, parasitic and inflammatory conditions. The aim of this study was to evaluate the antigenotoxic and antioxidant activities induced by mimosa (M. caesalpiniifolia) in multiple rodent organs subjected to intoxication with cadmium chloride. A total of 40 Wistar rats (8 weeks old, 250 g) were distributed into eight groups (n = 5), as follows: Control group (non-treated group, CTRL); Cadmium exposed group (Cd); cadmium exposure and treated with extract at 62.5 mg/kg/day; cadmium exposure and treated with extract at 125 mg/kg/day; cadmium exposure and treated with extract at 250 mg/kg/day; cadmium exposure and treated with ethyl acetate fraction at 62.5 mg/kg/day. For evaluating the toxicogenetic potential of mimosa, two groups were included in the study being treated with extract at 250 mg/kg/day and acetate fraction of mimosa at 62 mg/kg/day, only. Extract of mimosa at concentrations of 62.5 and 125 mg decreased DNA damage in animals intoxicated with cadmium when compared to cadmium group. In a similar manner, treatment with ethyl acetate fraction of mimosa at 62.5 mg concentration in animals previously exposed to cadmium reduced genetic damage in peripheral blood cells. In a similar manner, the treatment with ethyl acetate fraction reduced DNA damage in liver cells. Oxidative DNA damage was reduced to animals exposed to cadmium and treated with 125 mg of extract as well as those intoxicated to cadmium and treated with 62.5 of acetate fraction of mimosa. Taken together, our results indicate that mimosa prevents genotoxicity induced by cadmium exposure in liver and peripheral blood cells of rats as a result of antioxidant activity.

Paradoxical Reaction during Treatment of Tuberculous Meningoencephalitis in a Patient with Systemic Lupus Erythematosus.

Tuberculous paradoxical reaction presents as clinical deterioration during appropriate tuberculosis therapy and is a separate entity from treatment failure and drug resistance. We describe a case of central nervous system paradoxical reaction following tuberculous meningoencephalitis treatment in an immunocompromised patient with systemic lupus erythematosus.

Limb compression induces multi-system genetic damage in rats.

Muscle crush injury is a common trauma in the modern society after as a result of mass disasters after penetration into muscle by high-velocity projectiles, blunt external trauma, or by gravity during prolonged immobilization in comatose patients after head trauma, alcoholic or drug overdose. However, the underlying mechanisms linking these alterations are still not fully understood, especially in acute phase. The aim of this study was to analyze genomic instability in multiple organs of rats after acute muscle injury by means of single cell gel (comet) assay. Rats were randomly distributed into three groups (n=6 each group): control group and experimental groups: sacrificed 6h as 12h after muscle compression. These results indicate genetic damage in peripheral blood cells as depicted by tail moment results. DNA breakage was also detected in liver, lung and kidney cells after acute muscle injury for two times evaluated. Heart cells showed genetic damage after 12h following muscle compression. Taken together, our results suggest that acute muscle injury induces genomic damage in multiple organs of Wistar rats. This novel finding offers new insights into the underlying mechanisms of the relationship between acute crush muscle injury and clinical manifestations that can occur during limb compression.

Helium-neon laser improves bone repair in rabbits: comparison at two anatomic sites.

The purpose of this study was to evaluate the influence of helium-neon laser on bone repair of femur and tibia in rabbits. For this purpose, 15 New Zealand rabbits underwent bilateral bone damage (tibia and femur) using a spherical bur. Helium-neon laser light, at a fluency of 6 J∕cm(2) and wavelength of 632.8 nm was applied on the left legs (laser group). The right tibia or femur lesions (control group) served as negative control. All sections were histopathologically analyzed using HE sections and the morphometric data from bone tissue and hyaline cartilage were achieved. Histopathological analysis showed regular bone trabeculae covered by osteoblastic cells after 1 week in the group exposed to laser therapy from femur and tibia indistinctly. After 3 weeks, the laser group showed new bone formation coming from the bony walls in the femur and tibia as well. On the 5th week, well-defined trabecula undergoing remodeling process was detected for the most intense pattern in tibia only. Morphometric analysis revealed significant statistical differences (p < 0.05) in the bone tissue for the laser-exposed group on 1st and 3rd weeks. After 5th week, bone formation was increased to tibia only. Taken together, such findings suggest that helium-neon laser is able to improve bone repair in rabbits being the most pronounced effect in tibia.

Nandrolone decanoate induces genetic damage in multiple organs of rats.

To evaluate the impact potential of nandrolone decanoate on DNA damage in multiple organs of Wistar rats by means of single-cell gel (comet) assay and micronucleus test. A total of 15 animals were distributed into three groups of five animals each as follows: control group = animal not exposed to nandrolone decanoate; experimental group = animals exposed to nandrolone decanoate for 24 h at 5 mg/kg subcutaneously; and experimental group = animals exposed to nandrolone decanoate for 24 h at 15 mg/kg subcutaneously. Significant statistical differences (p < 0.05) were noted in peripheral blood, liver, and heart cells exposed to nandrolone decanoate at the two doses evaluated. A clear dose-response relationship was observed between groups. Kidney cells showed genetic damage at only the highest dose (15 mg/kg) used. However, micronucleus data did not show remarkable differences among groups. In conclusion, the present study indicates that nandrolone decanoate induces genetic damage in rat blood, liver, heart, and kidney cells as shown by single-cell gel (comet) assay results.

DNA damage, p53, Ki-67 and COX-2 expression in rat tongue cells exposed to nandrolone decanoate.

The objective of this article was to evaluate the impact potential of nandrolone decanoate on DNA damage, cellular regulatory proteins and cyclooxygenase (COX)-2 in oral mucosa cells of Wistar rats. A total of 40 rats were distributed into four groups. Two experimental groups were treated with nandrolone decanoate, at 5 mg/kg doses, subcutaneously, three times a week in two periods: 15 and 30 days. The remaining groups received only 0.9% saline subcutaneously, three times a week. To evaluate genetic damage, nandrolone decanoate at 15 mg/kg dose was exposed to 24 h. In the histopathological analysis, no remarkable morphological changes were observed in tongue tissue in all groups. Significant increase in immunoexpression of Ki-67, p53, COX-2 proteins was detected in the groups treated with nandrolone decanoate during 15 and 30 days, when compared to their respective controls. A positive correlation between immunoexpression of p53 and COX-2 protein was detected following nandrolone decanoate exposure. DNA damage was induced by nandrolone decanoate in oral mucosa cells at 15 mg/kg dose. Our results suggest that nandrolone decanoate was able to alter the expression of cell cycle-related proteins, as well as to induce genetic damage and COX-2 immunoexpression in tongue cells of Wistar rats.

Differential response of heat shock proteins to uphill and downhill exercise in heart, skeletal muscle, lung and kidney tissues.

Running on a horizontal plane is known to increase the concentration of the stress biomarker heat-shock protein (HSP), but no comparison of the expression of HSP70 has yet been established between the uphill (predominantly concentric) and downhill (predominantly eccentric) muscle contractions exercise. The objective of the study was to investigate the relationships between eccentric and concentric contractions on the HSP70 response of the lung, kidney, gastrocnemius, soleus and heart. Twenty-four male Wistar weanling rats were divided into four groups: non-exercised and three different grades of treadmill exercise groups: horizontal, uphill (+7%) and downhill (-7% of inclination). At the optimal time-point of six hours after the exercise, serum uric acid, creatine kinase (CK) and lactate dehydrogenase (LDH) were determined by standard methods and HSP70 by the Western blot analysis. HSP70 responds differently to different types of running. For kidney, heart, soleus and gastrocnemius, the HSP70 expression increased, 230, 180, 150 and 120% respectively of the reference (horizontal). When the contraction was concentric (uphill) and compared to downhill the increase in response of HSP70 was greater in 80% for kidney, 75% for gastrocnemius, 60% for soleus and 280% for the heart. Uric acid was about 50% higher (0.64 ± 0.03 mg·dL(-1)) in the uphill group as compared to the horizontal or downhill groups. Similarly, the activities of serum CK and LDH were both 100% greater for both the uphill and downhill groups as compared to the horizontal group (2383 ± 253 and 647.00 ± 73 U/L, respectively). The responsiveness of HSP70 appeared to be quite different depending on the type of tissue, suggesting that the impact of exercise was not restricted to the muscles, but extended to the kidney tissue. The uphill exercise increases HSP70 beyond the eccentric type and the horizontal running was a lower HSP70 responsive stimulus. Key PointsExercise can induce increases in HSP70 in the lung, kidney and heart, and in the soleus and gastrocnemius muscles, probably due to systemic alterations such as hypoxia, increase in temperature and the production of free radicals.Predominantly concentric contractions (running uphill), seem to be the most efficient way of increasing the HSP70 concentrations in the different tissues, followed by eccentric contraction (downhill) and lastly the concentric-eccentric cycle (horizontal).The energy demand, already known to influence HSP70, appears not to be the only factor responsible for the response of these proteins, considering that for the kidney and the soleus muscle, downhill running was more efficient in raising the HSP70 response than horizontal running.Future research should explore the mechanisms by which the eccentric, concentric and eccentric-concentric contractions are capable of influencing the responses of the heat shock proteins, opening possibilities for increasing the levels of these proteins in desirable situations, such as to protect against excess free radicals or injuries.

Online medical education: A student survey.

BACKGROUND: During COVID-19, medical schools transitioned to online learning as an emergency response to deliver their education programmes. This multi-country study compared the methods by which medical schools worldwide restructured the delivery of medical education during the pandemic. METHODS: This multi-country, cross-sectional study was performed using an internet-based survey distributed to medical students in multiple languages in November 2020. RESULTS: A total of 1,746 responses were received from 79 countries. Most respondents reported that their institution stopped in-person lectures, ranging from 74% in low-income countries (LICs) to 93% in upper-middle-income countries. While only 36% of respondents reported that their medical school used online learning before the pandemic, 93% reported using online learning after the pandemic started. Of students enrolled in clinical rotations, 89% reported that their rotations were paused during the pandemic. Online learning replaced in-person clinical rotations for 32% of respondents from LICs versus 55% from high-income countries (HICs). Forty-three per cent of students from LICs reported that their internet connection was insufficient for online learning, compared to 11% in HICs. CONCLUSIONS: The transition to online learning due to COVID-19 impacted medical education worldwide. However, this impact varied among countries of different income levels, with students from LICs and lower middle income countries facing greater challenges in accessing online medical education opportunities while in-person learning was halted. Specific policies and resources are needed to ensure equitable access to online learning for medical students in all countries, regardless of socioeconomic status.

Corrigendum to "Metabolic dysfunctions promoted by AIN-93G standard diet compared with three obesity-inducing diets in C57BL/6J mice" [Curr. Res. Physiol. (2022) 436-444].

[This corrects the article DOI: 10.1016/j.crphys.2022.11.001.].

Cytogenetic biomonitoring of peripheral blood and oral mucosa cells from car painters.

The aim of the present study was to comparatively evaluate genomic damage and cellular death in exfoliated oral mucosa cells and peripheral blood from car painters. A total of 24 car painters and 19 healthy controls (non-exposed individuals) were included in this setting. Individuals had epithelial cells from cheek mucosa (left and right side) mechanically exfoliated, placed in fixative and dropped in clean slides which were checked for the specific nuclear phenotypes. A total of 5 µL from peripheral blood was collected for the single cell gel (comet) assay. The results pointed out statistically significant differences (p < 0.05) of micronucleated oral mucosa cells from car painters. In addition, DNA damage was detected in peripheral blood cells by single cell gel (comet) assay. Nevertheless, exposure to car paints did not cause increases other nuclear alterations closely related to cytotoxicity such as karrhyorexis, pyknosis and karyolysis in buccal mucosa cells. In summary, the results of the present study suggest that car painters comprise a high risk group since paints can induce genotoxic and mutagenic effects in peripheral blood and oral mucosa cells, respectively.

The impact of COVID-19 on routine pediatric vaccination delivery in Brazil.

INTRODUCTION: Childhood vaccination rates have decreased significantly during the COVID-19 pandemic. The Brazilian immunization program, Programa Nacional de Imunização (PNI), is a model effort, achieving immunization rates comparable to high-income countries. This study aimed to evaluate the impact of the COVID-19 pandemic in pediatric vaccinations administered by the PNI, as a proxy of adherence to vaccinations during 2020. METHODS: Data on the number of vaccines administered to children under 10 years of age nationally and in each of Brazil's five regions were extracted from Brazil's federal health delivery database. Population adjusted monthly vaccination rates from 2015 through 2019 were determined, and autoregressive integrated moving average (ARIMA) models were used to forecast expected vaccinated rates in 2020. We compared the forecasts to reported vaccine administrations to assess adequacy of pediatric vaccine delivery during the COVID-19 pandemic. RESULTS: From January 2015 to February 2020, the average rate of vaccine administration to children was 53.4 per 100,000. After February 2020, this rate decreased to 50.4, a 9.4% drop compared to 2019 and fell outside of forecasted ranges in December 2020. In Brazil's poorest region, the North, vaccine delivery fell outside of the forecasted ranges earlier in 2020 but subsequently rebounded, meeting expected targets by the end of 2020. However, in Brazil's wealthiest South and Southeast regions, initial vaccine delivery fell and remained well below forecasted rates through the end of 2020. CONCLUSION: In Brazil, despite a model national pediatric vaccination program with an over 95% national coverage, vaccination rates decreased during the COVID-19 pandemic. Coordinated governmental efforts have ameliorated some of the decrease, but more efforts are needed to ensure continued protection from preventable communicable diseases for children globally.

Cytotoxicity, Inflammatory Activity, and Angiogenesis Are Induced by Different Silicone Implants.

BACKGROUND/AIM: The aim of this study was to investigate cytotoxicity, inflammatory response, and angiogenesis induced by silicone gel breast implants with different textured surfaces in vitro and in vivo. MATERIALS AND METHODS: In the in vitro study, murine fibroblast cells (L929) were cultured for 1, 3, and 5 days with silicone membranes of three different textures: nanotextured, microtextured, and silicone foam. In the in vivo study, a total of 30 male rats (Rattus, norvegicus, albinos, Wistar) were distributed into three groups (10 animals per group), with 2 implants in each rat: nanotextured silicone gel breast implants group, microtextured silicone gel breast implants group, and silicone gel breast foam implants group. RESULTS: The Alamar Blue assay detected higher viability of cells cultured in the presence of nanotextured silicone surface for 1 and 3 days. The MTT assay showed higher cytotoxicity of silicone foam after 1 and 3 days of exposure. Nanotextured silicone breast implants induced a more prolonged inflammatory response, denoting a delay in the healing process and subsequent organization of the fibrous capsule as depicted by the collagen fiber types found. VEGF expression did not differ between experimental groups. CONCLUSION: Gel foam breast implants are more biocompatible when compared to micro- or nano-textured silicone breast implants.

Is authorship by women in Brazilian academic surgery increasing? A five-year retrospective analysis.

Women remain underrepresented in 80% of Brazilian surgical specialties, however, women representation within the Brazilian academic surgical literature remains unknown. This study aims to evaluate the gender distribution of first and last authors in Brazilian surgical journals. All publications between 2015 and 2019 from the five Brazilian surgical journals with the highest impact factor were reviewed. The first and last authors' names were extracted from each article and a predictive algorithm was used to classify the gender of each author. Authors were further classified by surgical field and geographic region to investigate patterns of female authorship among journals, specialties, and region over the study period. Multivariable logistic regression was then used to identify factors independently associated with female authorship. 1844 articles were analyzed; 23% (426/1844) articles had female first authors, and 20% (348/1748) had female last authors. Acta Cirúrgica Brasileira was observed to have the highest rates for both first and last female authors (37%, 138/371; 26%, 95/370)) and Revista Brasileira de Ortopedia (9%, 48/542; 10%, 54/522) had the lowest rates. Papers with a woman senior author were twice as likely to have a woman first author (OR 1.98, 95% CI 1.51-2.58, p≤0.01). Women's representation in medicine is increasing in Brazil, yet women remain underrepresented as the first and last authors in the Brazilian surgical literature. Our results highlight the importance of senior women mentorship in academic surgery and demonstrate that promoting female surgeon senior authorship through academic and financial support will positively impact the number of female first authors.

Metabolic dysfunctions promoted by AIN-93G standard diet compared with three obesity-inducing diets in C57BL/6J mice.

Researchers from different fields have studied the causes of obesity and associated comorbidities, proposing ways to prevent and treat this condition by using a common animal model of obesity to create a profound energy imbalance in young adult rodents. However, to confirm the harmful effects of consuming a high-fat and hypercaloric diet, it is common to include normolipidic and normocaloric control groups in the experimental protocols. This study compared the effect of three experimental diets described in the literature - namely, a high-fat diet, a high-fat and high-sucrose diet, and a high-fat and high-fructose diet - to induce obesity in C57BL/6 J mice with the standard AIN-93G diet as a control. We hypothesize that the AIN diet formulation is not a good control in this type of experiment because this diet promotes weight gain and metabolic dysfunctions similar to the hypercaloric diet. The metabolic data of animals fed the AIN-93G diet were similar to those of the high-calorie groups (development of steatosis and hyperlipidemia). However, it is important to emphasize that the group fed a high-fat diet had a higher percentage of total fat (p = 0.0002) and abdominal fat (p = 0.013) compared to the other groups. Also, the high-fat group responded poorly to glucose and insulin tolerance tests, showing a picture of insulin resistance. As expected, the intake of the AIN-93G diet promotes metabolic alterations in the animals like the high-fat formulations. Therefore, although this diet continues to be used as the gold standard for growth and maintenance, it warrants a reassessment of its composition to minimize the metabolic changes observed in this study, thus updating its fitness as a normocaloric model of a standard rodent diet.