Filamentous actin destabilization by H2O2 favors DnmA aggregation, with crucial roles of cysteines 450 and 776 in mitochondrial and peroxisomal division in Aspergillus nidulans.

IMPORTANCE: Mitochondria constitute major sources of H2O2 and other reactive oxygen species in eukaryotic cells. The division of these organelles is crucial for multiple processes in cell biology and relies on highly regulated mechano-GTPases that are oligomerization dependent and belong to the dynamin-related protein family, like A. nidulans DnmA. Our previous work demonstrated that H2O2 induces mitochondrial constriction, division, and remodeling of the outer membrane. Here, we show that H2O2 also induces a DnmA aggregation consistent with higher-order oligomerization and its recruitment to mitochondria. The study of this response uncovered that H2O2 induces the depolymerization and reorganization of actin as well as the critical role that cysteines 450 and 776 play in DnmA function. Our results provide new insights into the mechanisms of reactive oxygen species cell signaling and how they can regulate the dynamics of the actin cytoskeleton and the division of mitochondria and peroxisomes.

The IV International Symposium on Fungal Stress and the XIII International Fungal Biology Conference.

For the first time, the International Symposium on Fungal Stress was joined by the XIII International Fungal Biology Conference. The International Symposium on Fungal Stress (ISFUS), always held in Brazil, is now in its fourth edition, as an event of recognized quality in the international community of mycological research. The event held in São José dos Campos, SP, Brazil, in September 2022, featured 33 renowned speakers from 12 countries, including: Austria, Brazil, France, Germany, Ghana, Hungary, México, Pakistan, Spain, Slovenia, USA, and UK. In addition to the scientific contribution of the event in bringing together national and international researchers and their work in a strategic area, it helps maintain and strengthen international cooperation for scientific development in Brazil.

The role of peroxiredoxins PrxA and PrxB in the antioxidant response, carbon utilization and development in Aspergillus nidulans.

In addition to their role in the breakdown of H2O2, some peroxiredoxins (Prxs) have chaperone and H2O2 sensing functions. Acting as an H2O2 sensor, Prx Gpx3 transfers the oxidant signal to the transcription factor Yap1, involved in the antioxidant response in Saccharomyces cerevisiae. We have shown that Aspergillus nidulans Yap1 ortholog NapA is necessary for the antioxidant response, the utilization of arabinose, fructose and ethanol, and for proper development. To address the Prx roles in these processes, we generated and characterized mutants lacking peroxiredoxins PrxA, PrxB, PrxC, or TpxC. Our results show that the elimination of peroxiredoxins PrxC or TpxC does not produce any distinguishable phenotype. In contrast, the elimination of atypical 2-cysteine peroxiredoxins PrxA and PrxB produce different mutant phenotypes. ΔprxA, ΔnapA and ΔprxA ΔnapA mutants are equally sensitive to H2O2 and menadione, while PrxB is dispensable for this. However, the sensitivity of ΔprxA and ΔprxA ΔnapA mutants is increased by the lack of PrxB. Moreover, PrxB is required for arabinose and ethanol utilization and fruiting body cell wall pigmentation. PrxA expression is partially independent of NapA, and the replacement of peroxidatic cysteine 61 by serine (C61S) is enough to cause oxidative stress sensitivity and prevent NapA nuclear accumulation in response to H2O2, indicating its critical role in H2O2 sensing. Our results show that despite their high similarity, PrxA and PrxB play differential roles in Aspergillus nidulans antioxidant response, carbon utilization and development.

Inhibition of the CYP Enzymatic System Responsible of Heterocyclic Amines Bioactivation by an Asclepias subulata Extract.

Asclepias subulata plant extract has previously demonstrated antiproliferative activity and antimutagenicity against heterocyclic aromatic amines (HAAs) commonly found in cooked meat. The objective of this work was to evaluate the in vitro ability of an ethanolic extract from the medicinal plant Asclepias subulata extract (ASE), non-heated and heated (180 °C), to inhibit the activity of CYP1A1 and CYP1A2, which are largely responsible for HAAs bioactivation. Ethoxyresorufin and methoxyresorufin O-dealkylation assays were performed in rat liver microsomes exposed to ASE (0.002-960 µg/mL). ASE exerted an inhibitory effect in a dose-dependent manner. The half inhibitory concentration (IC50) for unheated ASE was 353.6 µg/mL and 75.9 µg/mL for heated ASE in EROD assay. An IC40 value of 288.4 ± 5.8 µg/mL was calculated for non-heated ASE in MROD assay. However, after heat treatment, the IC50 value was 232.1 ± 7.4 µg/mL. Molecular docking of corotoxigenin-3-O-glucopyranoside, one of the main components of ASE, with CYP1A1/2 structure, was performed. Results show that the interaction of corotoxigenin-3-O-glucopyranoside with CYP1A1/2s' α-helices, which are related with the active site and the heme cofactor, may explain the plant extract's inhibitory properties. Results showed that ASE inhibits CYP1A enzymatic subfamily and may potentially act as a chemopreventive agent by inhibiting bioactivation of promutagenic dietary HAAs.

Capillary Refill Time and Serum Lactate as Predictors of Mortality and Postoperative Extracorporeal Membrane Oxygenation Requirement in Congenital Heart Surgery.

Multiple tissue perfusion markers are described to guide therapy in critically ill pediatric patients undergoing congenital heart surgery. Given the advantages of capillary refill time, our goal is to determine its predictive capacity for mortality and postoperative extracorporeal oxygenation requirements in congenital heart surgery and compare it to serum lactate. We conducted a prospective cohort observational study in a single high-complexity university hospital. Serum lactate and capillary refill time were measured at five predetermined time points: preoperative, immediate postoperative, 6, 12, and 24 h after the surgery. Prolonged immediate postoperative, 6 h, and 12 h capillary refill time measurements turned out to be independent risk factors for both outcomes. The capillary refill time area under the curve ranged between 0.70 and 0.80, while the serum lactate resulted between 0.79 and 0.92 for both outcomes. Both tissue perfusion markers resulted in mortality and extracorporeal oxygenation requirement predictors. Given the advantages of capillary refill time over serum lactate, a monitoring strategy including these two perfusion markers should be considered for congenital heart surgeries.

A Fatal Case of Systemic Calciphylaxis in the Gastrointestinal Tract: A Case Report and Literature Review.

Calciphylaxis is an infrequent yet lethal disease often associated with end-stage kidney disease (ESKD). The most common sites include proximal and distal extremities and the trunk, with few reported in the penis and very few as gastrointestinal (GI) disease. We report a case of systemic calciphylaxis in a middle-aged male, presenting with a colostomy leak and parastomal abscess. Workup revealed severe calcification of the intestinal arteries and ischemic colon necrosis. The patient underwent colectomy, antibiotic therapy, regular hemodialysis (HD), and sodium thiosulphate infusion with clinical stability. Histopathology of the colon revealed ischemic necrosis and pericolonic vessel calcification suggestive of calciphylaxis. It is an important differential to be considered in patients with risk factors presenting with symptoms of gastrointestinal hemorrhage and necrosis with perforation.

Metabolic-associated Fatty Liver Disease Regulation through Nutri Epigenetic Methylation.

Metabolically associated fatty liver disease, formerly called nonalcoholic fatty liver disease, is the most common liver disease globally, representing the third cause of liver transplantation. Metabolically associated fatty liver disease is defined as having more than 5% lipid droplets in hepatocytes without other concomitant liver diseases. Various stimuli such as the secretion of inflammatory cytokines, mitochondrial and endoplasmic reticulum dysfunction due to oxidative stress, alteration of the intestine-liver axis, bacterial dysbiosis, as well as genetic and epigenetic factors can modify the progression of metabolically associated fatty liver disease to fibrosis, cirrhosis, and may reach hepatocellular carcinoma. Epigenetics is responsible for a highly sophisticated regulatory system that controls many cellular processes in response to multiple environmental factors as an adaptive mechanism unrelated to alterations in the primary deoxyribonucleic acid sequence, including gene expression, microRNAs, DNA methylation, modifications in histones, and DNA-protein interactions. Several studies have shown that epigenetic changes are associated with various diseases, including metabolically associated fatty liver disease. Nutri epigenomics is the interaction between nutrition and components at the transcriptional or post-transcriptional level. Methylation processes involve micronutrients that regulate epigenetic states in a physiological and pathological context. Micronutrients such as methionine, folate, and choline are the main components of one-carbon metabolism, functioning as methyl group donors, and their deficiency predisposes to various pathologies such as metabolically associated fatty liver disease. Understanding of epigenetic modifiers leads us to develop new therapeutic therapies for patients with metabolically associated fatty liver disease.

Essential-Oils-Loaded Biopolymeric Nanoparticles as Strategies for Microbial and Biofilm Control: A Current Status.

The emergence of bacterial strains displaying resistance to the currently available antibiotics is a critical global concern. These resilient bacteria can form biofilms that play a pivotal role in the failure of bacterial infection treatments as antibiotics struggle to penetrate all biofilm regions. Consequently, eradicating bacteria residing within biofilms becomes considerably more challenging than their planktonic counterparts, leading to persistent and chronic infections. Among various approaches explored, essential oils loaded in nanoparticles based on biopolymers have emerged, promising strategies that enhance bioavailability and biological activities, minimize side effects, and control release through regulated pharmacokinetics. Different available reviews analyze nanosystems and essential oils; however, usually, their main goal is the analysis of their antimicrobial properties, and progress in biofilm combat is rarely discussed, or it is not the primary objective. This review aims to provide a global vision of biofilm conformation and describes mechanisms of action attributed to each EO. Furthermore, we present a comprehensive overview of the latest developments in biopolymeric nanoparticles research, especially in chitosan- and zein-based nanosystems, targeting multidrug-resistant bacteria in both their sessile and biofilm forms, which will help to design precise strategies for combating biofilms.

H2O2 Induces Calcium and ERMES Complex-Dependent Mitochondrial Constriction and Division as Well as Mitochondrial Outer Membrane Remodeling in Aspergillus nidulans.

The dynamin-like protein DnmA and its receptor FisA are essential for H2O2-induced mitochondrial division in Aspergillus nidulans. Here, we show that in the absence of DnmA or FisA, mitochondria show few spontaneous transient constrictions, the frequency of which is extensively increased by H2O2 or the carbonyl cyanide m-chlorophenyl hydrazone (CCCP). While H2O2-induced constrictions are transient, CCCP induces a drastic and irreversible alteration of mitochondrial filaments. H2O2 induces a gradual mitochondrial depolarization, while CCCP-induced depolarization is abrupt. The calcium chelator BAPTA-AM prevents the formation of mitochondrial constrictions induced by either H2O2 or CCCP. H2O2 also induces major rearrangements of the mitochondrial outer membrane, which remain after constrictions dissipate, as well as changes in endoplasmic reticulum (ER) and nuclear morphology. Similar mitochondrial constriction, ER and nuclear morphology changes are detected during the early stages of asexual development. ER and ER-Mitochondria encounter structure (ERMES) complex-composed of proteins Mdm10, Mmm1, Mdm43 and Mdm12-are important for mitochondrial division in Saccharomyces cerevisiae. As the Mdm10 ortholog MdmB was found to be essential in A. nidulans, we evaluated its functions in ΔmdmB terminal mutants and ΔmdmB heterokaryons. ΔmdmB conidia produce a short germ tube that fails to grow further, in which inherited mitochondria become gigantic and round shaped, lacking clear contacts with the ER. In slow-growing ΔmdmB heterokaryotic mycelia, multiple hyphae contain very long mitochondria with high ROS levels, as occur in ΔdnmA and ΔfisA mutants. In this hyphae, H2O2 fails to induce mitochondrial constrictions but not outer mitochondrial membrane reshaping, indicating that these are two separate effects of H2O2. Our results indicate that H2O2 induces a generalized mitochondrial constriction response, prior to actual division, involving gradual depolarization; they also indicate that Ca2+ and the ERMES complex are critical for both mitochondrial constriction and division. This supports a view of mitochondrial dynamics as the result of a cascade of signaling events that can be initiated in vivo by H2O2.

Expression of Cytochrome P450 Enzymes in Pediatric Non-Rhabdomyosarcoma Soft Tissue Sarcomas: Possible Role in Carcinogenesis and Treatment Response.

The 5-year relative survival rate estimate of treated patients with non-rhabdomyosarcoma soft tissue sarcomas (NRSTS) is ∼50% since they generally present with tumor progression, relapse, metastasis, and/or chemoresistance. The expression of cytochrome P450 (CYP) enzymes in malignancies can affect the pharmacology of drugs commonly used in chemotherapy or confer susceptibility to development of chemical carcinogenesis; in addition, their specific tumor expression can be used as a therapeutic target. Using qPCR and Western blot assays, the expression of CYP1B1, CYP2E1, CYP3A4, and CYP3A5 were analyzed in a cohort of tumor tissue paired with non-malignant adjacent tissue of patients with NRSTS. The mRNA and protein expression of CYP1B1, CYP2E1, and CYP3A4 were significantly increased in tumor tissue. We propose that the expression of these isoforms is related to carcinogenesis and chemoresistance frequently observed in these neoplasms.

Coping and adaptation of adults with cancer: the art of nursing care / Afrontamiento y adaptación del adulto con cáncer: el arte del cuidado de enfermería / Enfrentamento e adaptação do adulto com câncer: a arte do cuidado de enfermagem

Objective: To determine the coping and adaptive capabilities in patients with cancer undergoing treatment. Methodology: This was a quantitative and descriptive cross-sectional study; the sample consisted of 100 patients with a cancer diagnosis who received chemotherapy and/or radiotherapy treatment between June and August 2019, meeting the inclusion criteria. The Coping and Adaptation Processing Scale (CAPS) was used. Results: 53 % of the patients participating in the study presented high coping and adaptive capabilities; 40 % presented medium capabilities, and 7 % presented low capabilities. Conclusion: Continuous follow-up is extremely important throughout the disease process; having a romantic partner becomes a protective factor since patients feel heard and cared for, which motivates them to follow through with the treatment. In the nursing field, knowing the experience of those who live with an illness allows for transcending and impacting care by providing holistic attention to patients.

Objetivo: determinar la capacidad de afrontamiento y adaptación en personas con cáncer en tratamiento. Metodología: estudio cuantitativo y descriptivo de corte transversal; la muestra fue conformada por 100 pacientes con diagnóstico de cáncer que asistieron a tratamiento de quimioterapia y/o radioterapia entre junio y agosto del 2019, cumpliendo los criterios de inclusión. Se utilizó la Escala de Medición del Proceso de Afrontamiento y Adaptación (ESCAPS). Resultados: 53% de los pacientes estudiados poseen una capacidad de afrontamiento y adaptación alta; 40% obtuvo capacidad media y 7% una capacidad baja. Conclusión: el acompañamiento continuo es de gran importancia en todo el proceso de la enfermedad; tener una pareja sentimental se convierte en un factor protector pues los pacientes se sienten escuchados y atendidos, lo cual los motiva a continuar con el tratamiento. En el área de enfermería, conocer la experiencia de quienes viven una enfermedad permite trascender e impactar el cuidado brindando una atención holística.

Objetivo: determinar a capacidade de enfrentamento e adaptação em pessoas com câncer em tratamento. Materiais e método: estudo quantitativo e descritivo, de corte transversal; a amostra foi conformada de 100 pacientes com diagnóstico de câncer que passaram por tratamento de quimioterapia e/ou radioterapia entre junho e agosto de 2019, cumprindo com os critérios de inclusão. Foi utilizada a Escala de Medição do Processo de Enfrentamento e Adaptação. Resultados: 53 % dos pacientes estudados apresentaram capacidade de enfrentamento e adaptação alta; 40 % obtiveram capacidade média e 7 %, capacidade baixa. Conclusões: o acompanhamento contínuo é de grande importância em todo o processo da doença; ter um parceiro(a) sentimental se torna um fator protetor, pois os pacientes se sentem escutados e atendidos, o que os motiva a continuar com o tratamento. Na área de enfermagem, conhecer a experiência de quem vive uma doença permite transcender e impactar o cuidado, oferecendo uma atenção holística.

A survey study examining the motivations, concerns, and perspectives of medical students engaging in neurosurgical research.

BACKGROUND: In a competitive landscape for neurosurgical residency admission, research productivity is increasingly important. Medical school applicants to neurosurgery report high numbers of "scholarly products" as published by the National Residency Match Program. Despite increased student involvement in research and productivity, to the best of our knowledge, no previous reported studies have examined student perspectives on their involvement in neurosurgical research. METHODS: For 2 consecutive years (February 2019 and February 2020), medical students (n = 55) from around the United States presented original research at the Student Neurosurgical Research Conference. Participants were administered a mixed-method survey designed to assess experiences and perspectives on engaging in neurosurgical research. Survey responses were analyzed independently by two researchers to assess for common themes and perspectives. RESULTS: Medical students engaged in all types of research work across nearly every neurosurgical subfield with "Basic/Bench Lab work" (38.5%) and "Chart Review" (23.1%) representing the majority of projects. Students commonly cited "curiosity/interest," and "residency application competitiveness" as main reasons for participation in research. About 66% of respondents reported experiencing anxiety/concern about research productivity "often" or "very often." Thematic analysis revealed that sources of research-related stress were (1) having enough publications to match into residency, and (2) having enough time in medical school to engage in research. CONCLUSION: Medical students engaging in neurosurgical research are highly motivated students driven by scientific curiosity and pressure to prepare for competitive residency applications. Students experience anxiety due to time constraints in medical curricula and increasing demands for scholarly productivity.

H2O2 Induces Major Phosphorylation Changes in Critical Regulators of Signal Transduction, Gene Expression, Metabolism and Developmental Networks in Aspergillus nidulans.

Reactive oxygen species (ROS) regulate several aspects of cell physiology in filamentous fungi including the antioxidant response and development. However, little is known about the signaling pathways involved in these processes. Here, we report Aspergillus nidulans global phosphoproteome during mycelial growth and show that under these conditions, H2O2 induces major changes in protein phosphorylation. Among the 1964 phosphoproteins we identified, H2O2 induced the phosphorylation of 131 proteins at one or more sites as well as the dephosphorylation of a larger set of proteins. A detailed analysis of these phosphoproteins shows that H2O2 affected the phosphorylation of critical regulatory nodes of phosphoinositide, MAPK, and TOR signaling as well as the phosphorylation of multiple proteins involved in the regulation of gene expression, primary and secondary metabolism, and development. Our results provide a novel and extensive protein phosphorylation landscape in A. nidulans, indicating that H2O2 induces a shift in general metabolism from anabolic to catabolic, and the activation of multiple stress survival pathways. Our results expand the significance of H2O2 in eukaryotic cell signaling.

Daytime Restricted Feeding Modifies the Temporal Expression of CYP1A1 and Attenuated Damage Induced by Benzo[a]pyrene in Rat Liver When Administered before CYP1A1 Acrophase.

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that heterodimerizes with the AhR nuclear translocator (ARNT) to modulate CYP1A1 expression, a gene involved in the biotransformation of benzo[a]pyrene (BaP). The AhR pathway shows daily variations under the control of the circadian timing system. Daytime restricted feeding (DRF) entrains the expression of genes involved in the processing of nutrients and xenobiotics to food availability. Therefore, we evaluate if temporal AhR, ARNT, and CYP1A1 hepatic expression in rats are due to light/dark cycles or fasting/feeding cycles promoted by DRF. Our results show that AhR oscillates throughout the 24 h period in DRF and ad libitum feeding rats (ALF), showing maximum expression at the same time points. DRF modified the peak of ARNT expression at ZT5; meanwhile, ALF animals showed a peak of maximum expression at ZT17. An increased expression of CYP1A1 was linked to the meal time in both groups of animals. Although a high CYP1A1 expression has been previously associated with BaP genotoxicity, our results show that, compared with the ALF group, DRF attenuated the BaP-CYP1A1 induction potency, the liver DNA-BaP adducts, the liver concentration of unmetabolized BaP, and the blood aspartate aminotransferase and alanine aminotransferase activities when BaP is administered prior to the acrophase of CYP1A1 expression. These results demonstrate that DRF modifies the ARNT and CYP1A1 expression and protects from BaP toxicity.

Osmolyte Signatures for the Protection of Aspergillus sydowii Cells under Halophilic Conditions and Osmotic Shock.

Aspergillus sydowii is a moderate halophile fungus extensively studied for its biotechnological potential and halophile responses, which has also been reported as a coral reef pathogen. In a recent publication, the transcriptomic analysis of this fungus, when growing on wheat straw, showed that genes related to cell wall modification and cation transporters were upregulated under hypersaline conditions but not under 0.5 M NaCl, the optimal salinity for growth in this strain. This led us to study osmolyte accumulation as a mechanism to withstand moderate salinity. In this work, we show that A. sydowii accumulates trehalose, arabitol, mannitol, and glycerol with different temporal dynamics, which depend on whether the fungus is exposed to hypo- or hyperosmotic stress. The transcripts coding for enzymes responsible for polyalcohol synthesis were regulated in a stress-dependent manner. Interestingly, A. sydowii contains three homologs (Hog1, Hog2 and MpkC) of the Hog1 MAPK, the master regulator of hyperosmotic stress response in S. cerevisiae and other fungi. We show a differential regulation of these MAPKs under different salinity conditions, including sustained basal Hog1/Hog2 phosphorylation levels in the absence of NaCl or in the presence of 2.0 M NaCl, in contrast to what is observed in S. cerevisiae. These findings indicate that halophilic fungi such as A. sydowii utilize different osmoadaptation mechanisms to hypersaline conditions.

Nefropatía por inmunoglobulina A en pediatría, desenlaces clínicos con diferentes esquemas de manejo / IgA nephropathy in pediatric patients, clinical outcomes with three types of management

Resumen Introducción: la nefropatía por inmunoglobulina A (NIgA) es la enfermedad glomerular más común en el mundo. En Colombia, el 11-22 % de las glomerulonefritis primarias en niños corresponden a NIgA y de estos casos, el 30 % progresa a enfermedad renal terminal. Objetivo: describir las características paraclínicas e histopatológicas de la NIgA, así como los resultados clínicos según tres tipos de tratamiento en pacientes pediátricos con esta enfermedad atendidos en un hospital de alta complejidad del suroccidente colombiano. Materiales y métodos: estudio retrospectivo realizado en pacientes pediátricos de entre 1 mes y 18 años de edad con diagnóstico de NIgA. Las variables categóricas se presentaron como proporciones y las continuas con medianas y rango intercuartílico. Se usó la prueba de Fisher para comparar los tres esquemas de tratamiento. Resultados: se incluyeron 58 pacientes pediátricos atendidos entre 1996 y 2013. La media de edad al inicio de síntomas fue 7,5±4,2 años y al momento de la biopsia renal, 10±3,8 años. El 77,6 % de los pacientes presentó hematuria microscópica y el 27,6 %, macroscópica. Además, el 81 % tuvo proteinuria, siendo severa el 29 %. Histológicamente, el 10 % se clasificó como grado I, el 62 % como grado II, el 21 % como grado III y el 7 % como grado IV. Tres pacientes requirieron diálisis y dos, trasplante renal. Los esquemas terapéuticos evaluados fueron: solo prednisona (n=20, 34,5 %), prednisona y mofetil micofenolato (MMF) (n=13, 22,4 %) y sin prednisona ni MMF (n=25, 43,1 %). La diferencia en la presencia de hematuria entre los grupos fue significativa (p>0,001), siendo más frecuente en el grupo sin prednisona ni MMF (68 %). No hubo diferencia entre los grupos de proteinuria, hipertensión arterial y valor de creatinina. La mediana de años entre la biopsia renal y el ultimo control fue de 4 años (RIC 1-7). La supervivencia de la función renal fue del 89,1 % a los 5 años. Conclusión: la NIgA amerita reconocimiento temprano y seguimiento estricto, ya que puede tener desenlaces ominosos como enfermedad renal crónica.

Abstract Introduction: IgA nephropathy (IgAN) is the most common glomerular disease in the world, in Colombia belongs to 11-22 % of primary glomerulonephritis in pediatric patients. Of these, 30 % progress to chronic kidney disease. Materials and methods : It is a retrospective descriptive study. We used median and IRQ for continuous variables, and proportions for categorical variables, Fisher test to compare clinical outcomes. Results: Between 1996 to 2013 58 patients were diagnosed. The mean age at symptoms onset was 7.5 years (SD±4.2) and at the time of renal biopsy was 10 years (SD±3.8). At diagnosis, 77.6 % of the patients showed microscopic hematuria, 27.6 % gross hematuria and 81 % proteinuria, classified as severe in 29 %. Three patients required dialysis and two needed kidney transplant. Three groups with different therapeutic regimens were evaluated: first group only prednisone 34.5 % (n = 20), second group prednisone and mycophenolate mofetil (MMF) 22.4 % (n = 13) and third group without prednisone neither MMF 43.1 % (n = 25). The difference in the presence of hematuria among the groups was significant (p> 0.001), being more frequent in the group without prednisone neither MMF (68 %). There were no significant differences in proteinuria, hypertension or creatinine among the groups. The median of years between the renal biopsy and the last control was 4 years RI 1-7. At five years, the renal function survival probability (GFR >90 ml/min/1.73m2) was 89.1 %. Conclusion: IgAN needs early recognition and strict follow-up, since it may have ominous outcomes.

Acetylcholinesterase activity in fish species exposed to crude oil hydrocarbons: A review and new perspectives.

Crude oil and its derivatives are primary energy resources for humans, and processes involving these materials could affect aquatic environments. Acetyl cholinesterase (AChE) activity is a suitable biomarker for exposure to organophosphate pesticides. Under controlled conditions, fish exposed to polycyclic aromatic hydrocarbons (PAHs), such as benzo[a]pyrene, pyrene and anthracene, showed inhibition of this biomarker; however, PAHs with a low molecular weight did not induce changes or cause stimulation of AChE activity. Diverse responses of fish exposed to soluble fractions of crude oil, fuels or gasoline were documented. Most studies in which AChE activity was considered for environmental monitoring have been performed to evaluate the presence of pesticides, and the effects of petroleum hydrocarbons are unclear. The objective of this review was to provide the recent status of research on this topic and suggest proposals for future investigations. To establish the suitability of this biomarker in fish species exposed to these pollutants and to determine their neurotoxic effects, researchers must determinate the mechanism involved in the AChE inhibition by petroleum hydrocarbons, unify criteria concerning the experimental in vitro and in vivo designs and apply multivariate statistical and correlation analyses between these pollutants with AChE activity in field studies.

The National Student Neurosurgical Research Conference: A Research Conference for Medical Students.

OBJECTIVE: Medical students interested in neurosurgery are increasingly involved in research, and research conferences have proven valuable for developing medical research experience and exposure. A research conference was designed for medical students interested in neurosurgery to present research. METHODS: Our team designed an annual research conference at the Warren Alpert Medical School of Brown University in conjunction with the Neurosurgery and Neurology Departments. In February 2019, we hosted the first Student Neurosurgical and Neurological Research Conference (SNRC), the first national research conference, to our knowledge, designed for medical students to present neurosurgical research in the United States. The conference consisted of student poster/oral presentations, keynote speeches from clinical faculty, and surgical skills workstations. In February 2020, we hosted the second SNRC. After each conference, participants (n = 55) completed a survey to assess student perspectives of the conference. RESULTS: Fifty-five medical students from around the nation attended the conferences to present their research. One hundred percent of participants affirmed that the conference fulfilled their primary reason for attending, which for most (54.5%) was the opportunity to present research. Thematic analysis revealed that students especially appreciated the "lower stress environment" and "opportunity to get feedback on their research." Notably, 97.6% of students felt the conference strengthened or increased their interest in neurosurgery. CONCLUSIONS: Participants felt that the SNRC was a valuable opportunity to present research in an environment conducive for practice and improvement. Research conferences primarily for medical students may support the development of young researchers while increasing and strengthening interest in the field of neurosurgery.

Structure-Activity Relationship (SAR) and in vitro Predictions of Mutagenic and Carcinogenic Activities of Ixodicidal Ethyl-Carbamates.

Ethyl-4-bromophenyl-carbamate (LQM 919) and Ethyl-4-chlorophenyl-carbamate (LQM 996) are compounds that inhibit egg-laying and hatching of tick larvae that are resistant to conventional ixodicides. The structure-activity relationship (SAR) to get the endpoint predictions of mutagenicity and carcinogenicity of the LQM 919 and LQM 996 was performed and the absence of mutagenicity was confirmed by Ames test. SAR analysis show no structural alerts indicating the ability of ethyl-carbamates to bind biomolecules or estrogen receptors. Endpoint of mutagenicity with and without metabolic activation showed that the ethyl-carbamates were negative (p <0.05) for mutagenicity induction in strains TA97, TA98, TA102, TA1535, TA1537 and TA1538 of Salmonella typhimurium. Pre-incubation with different ethyl-carbamate concentrations did not increase the number of spontaneously reverting colonies; moreover, the compounds did not induce a concentration-dependent increase in the number of reverting colonies in any of the strains used. This confirmed the absence of mutagenic activity in this test system. Exogenous metabolic activation did not modify these observations; suggesting that no metabolites with mutagenic activity were present. The endpoint of carcinogenicity in rats were negative for LQM 919 (p <0.05,) and LQM 996 (p <0.001). The results of the present study strongly suggest that ethyl-carbamates do not represent a risk for cancer in mammals.