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Introduction: Few studies are available on the acute effects of motor racing on race drivers lactacidemia and blood glucose. Objective: To verify changes in lactacidemia and glycemia of race car drivers in the Old Stock Race category. Method: The concentrations of plasma lactate and glycemia of eight male race car drivers in the Old Stock Race category (OSR) were recorded thirty minutes before the start and ten minutes after the start of the race. The data were obtained during the 4th round of the 2018 Season of the OSR held at the Jos Carlos Pace race track (Interlagos / So Paulo-Brazil). For comparison between moments, paired Students t-test paired on variables with normal distribution was used, with Bonferronis post-test, adopting a 5% significance level, for all analyses. Descriptively the data were compared using the Percentage Delta and presented in graphical and tabular form.Results: It was found that the lactate concentration increased significantly after the race (2.26 + 0.76 vs. 3.56 + 0.97 mmol / L, p = 0.0101). On the other hand, there was no change in blood glucose (122 +15.3 vs. 123 + 19.8 mg / dl, p = 0.8828).Conclusion: The significant increase in lactacidemia after the race indicates that there was an anaerobic muscle requirement during the race. On the other hand, there was no change in the mean blood glucose after the race.Key Words:Motor Racing, Human Performance, Exercise, Experimental Research

Sickle cell anemia is a hereditary disease caused by sickle-shaped red blood cells that can lead to vaso-occlusive crises. Treatment options are currently limited, highlighting the need to develop new clinical approaches. Studies demonstrated that elevated levels of fetal hemoglobin (Hb F) are associated with a reduction of mortality and morbidity in sickle cell anemia patients. In light of this, researchers have been trying to elucidate the transcriptional regulation of Hb F to develop new therapeutic interventions. The present study aimed to present the main transcription factors of Hb F and discuss the clinical feasibility of these molecular targets. Two search strategies were used in the PubMed, SciELO, and LILACS databases between July and August 2023 to conduct this review. Manual searches were also conducted by checking references of potentially eligible studies. Eligibility criteria consisted of clinical trials and cohort studies from the last five years that investigated transcription factors associated with Hb F. The transcription factors investigated in at least four eligible studies were included in this review. As a result, 56 eligible studies provided data on the BCL11A, LRF, NF-Y, GATA1, KLF1, HRI, ATF4, and MYB factors. The studies demonstrated that Hb F is cooperatively regulated by transcription factors with the BCL11A factor appearing to be the most specific target gene for γ-globin induction. Although these data are promising, there are still significant gaps and intervention limitations due to the adverse functions of the target genes. New studies that clarify the aspects and functionalities of Hb F regulators may enable new clinical approaches for sickle cell anemia patients., Competing Interests: Conflicts of interest The authors declare no conflicts of interest., (Copyright © 2024 Associação Brasileira de Hematologia, Hemoterapia e Terapia Celular. Published by Elsevier España, S.L.U. All rights reserved.)

Bone lesions have the capacity for regeneration under normal conditions of the bone metabolism process. However, due to the increasing incidence of major traumas and diseases that cause bone-mineral deficiency, such as osteoporosis, scaffolds are needed that can assist in the bone regeneration process. Currently, natural polymeric scaffolds and bioactive nanoparticles stand out. Therefore, the objective of the study was to evaluate the osteoregenerative potential in tibiae of healthy and ovariectomized rats using mineralized collagen and nanohydroxyapatite (nHA) scaffolds associated with elastin. The in-vivo experimental study was performed with 60 20-week-old Wistar rats, distributed into non-ovariectomized (NO) and ovariectomized (O) groups, as follows: Controls (G1-NO-C and G4-O-C); Collagen with nHA scaffold (G2-NO-MSH and G5-O-MSH); and Collagen with nHA and elastin scaffold (G3-NO-MSHC and G6-O-MSHC). The animals were euthanized 6 weeks after surgery and the samples were analyzed by macroscopy, radiology, and histomorphometry. ANOVA and Tukey tests were performed with a 95% CI and a significance index of p < 0.05. In the histological analyses, it was possible to observe new bone formed with an organized and compact morphology that was rich in osteocytes and with maturity characteristics. This is compatible with osteoconductivity in both matrices (MSH and MSHC) in rats with normal conditions of bone metabolism and with gonadal deficiency. Furthermore, they demonstrated superior osteogenic potential when compared to control groups. There was no significant difference in the rate of new bone formation between the scaffolds. Ovariectomy did not exacerbate the immune response but negatively influenced the bone-defect repair process.

Introduction: The optimal time for a neck ultrasound (US) in the follow-up of papillary thyroid cancer (PTC) after the first year is undetermined. We aimed to verify the utility of routine neck US in the surveillance of patients diagnosed with low- and intermediate-risk PTC with no evidence of disease at the one-year assessment., Subjects and Methods: We conducted a retrospective longitudinal study of patients with low- and intermediate-risk PTC with normal neck US, unstimulated serum thyroglobulin (Tg) < 1 ng/mL and negative anti-Tg antibodies at the one-year follow-up. Patients were divided into group 1 [undetectable Tg (<0.20 ng/mL)] and group 2 [detectable Tg but < 1 ng/mL]. The negative predictive value (NPV) of the one-year unstimulated Tg at the five-year and last follow-up visits was calculated., Results: We included n = 88 patients in group 1 and n = 8 patients in group 2. No patient from group 1 presented suspicious US findings at the five-year evaluation [NPV: 100.0% (95% confidence interval (CI): 95.5%-100.0%)], and at the last visit, only one patient had developed a lymph node classified as suspicious [NPV: 98.8% (95% CI: 93.2%-100.0%); mean follow-up: 6.7 years]. In group 2, two patients' USs presented suspicious findings at the five-year evaluation [NPV: 75.0% (95% CI: 34.9%-96.8%)]. At the last visit, only one patient persisted with suspicious findings in the US [NPV: 87.5% (95% CI: 47.4%-99.7%); mean follow-up: 6.5 years]., Conclusion: Low- and intermediaterisk PTC with an excellent response to treatment at the one-year assessment can be safely monitored with regular unstimulated Tg assessments. Conclusions should not be drawn for Tg levels between 0.20-0.99 ng/mL.

The aim of the present study was to evaluate the use of collagen, elastin, or chitosan biomaterial for bone reconstruction in rats submitted or not to experimental alcoholism. Wistar male rats were divided into eight groups, submitted to chronic alcohol ingestion (G5 to G8) or not (G1 to G4). Nasal bone defects were filled with clot in animals of G1 and G5 and with collagen, elastin, and chitosan grafts in G2/G6, G3/G7, and G4/G8, respectively. Six weeks after, all specimens underwent radiographic, tomographic, and microscopic evaluations. Bone mineral density was lower in the defect area in alcoholic animals compared to the abstainer animals. Bone neoformation was greater in the abstainer groups receiving the elastin membrane and in abstainer and alcoholic rats receiving the chitosan membrane (15.78 ± 1.19, 27.81 ± 0.91, 47.29 ± 0.97, 42.69 ± 1.52, 13.81 ± 1.60, 18.59 ± 1.37, 16.54 ± 0.89, and 37.06 ± 1.17 in G1 to G8, respectively). In conclusion, osteogenesis and bone density were more expressive after the application of the elastin matrix in abstainer animals and of the chitosan matrix in both abstainer and alcoholic animals. Chronic alcohol ingestion resulted in lower bone formation and greater formation of fibrous connective tissue.

Autologous bone grafts, used mainly in extensive bone loss, are considered the gold standard treatment in regenerative medicine, but still have limitations mainly in relation to the amount of bone available, donor area, morbidity and creation of additional surgical area. This fact encourages tissue engineering in relation to the need to develop new biomaterials, from sources other than the individual himself. Therefore, the present study aimed to investigate the effects of an elastin and collagen matrix on the bone repair process in critical size defects in rat calvaria. The animals (Wistar rats, n = 30) were submitted to a surgical procedure to create the bone defect and were divided into three groups: Control Group (CG, n = 10), defects filled with blood clot; E24/37 Group (E24/37, n = 10), defects filled with bovine elastin matrix hydrolyzed for 24 h at 37 °C and C24/25 Group (C24/25, n = 10), defects filled with porcine collagen matrix hydrolyzed for 24 h at 25 °C. Macroscopic and radiographic analyses demonstrated the absence of inflammatory signs and infection. Microtomographical 2D and 3D images showed centripetal bone growth and restricted margins of the bone defect. Histologically, the images confirmed the pattern of bone deposition at the margins of the remaining bone and without complete closure by bone tissue. In the morphometric analysis, the groups E24/37 and C24/25 (13.68 ± 1.44; 53.20 ± 4.47, respectively) showed statistically significant differences in relation to the CG (5.86 ± 2.87). It was concluded that the matrices used as scaffolds are biocompatible and increase the formation of new bone in a critical size defect, with greater formation in the polymer derived from the intestinal serous layer of porcine origin (C24/25).