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Snakes in the family Elapidae largely produce venoms rich in three-finger toxins (3FTx) that bind to the α 1 subunit of nicotinic acetylcholine receptors (nAChRs), impeding ion channel activity. These neurotoxins immobilize the prey by disrupting muscle contraction. Coral snakes of the genus Micrurus are specialist predators who produce many 3FTx, making them an interesting system for examining the coevolution of these toxins and their targets in prey animals. We used a bio-layer interferometry technique to measure the binding interaction between 15 Micrurus venoms and 12 taxon-specific mimotopes designed to resemble the orthosteric binding region of the muscular nAChR subunit. We found that Micrurus venoms vary greatly in their potency on this assay and that this variation follows phylogenetic patterns rather than previously reported patterns of venom composition. The long-tailed Micrurus tend to have greater binding to nAChR orthosteric sites than their short-tailed relatives and we conclude this is the likely ancestral state. The repeated loss of this activity may be due to the evolution of 3FTx that bind to other regions of the nAChR. We also observed variations in the potency of the venoms depending on the taxon of the target mimotope. Rather than a pattern of prey-specificity, we found that mimotopes modeled after snake nAChRs are less susceptible to Micrurus venoms and that this resistance is partly due to a characteristic tryptophan → serine mutation within the orthosteric site in all snake mimotopes. This resistance may be part of a Red Queen arms race between coral snakes and their prey., (© 2024. The Author(s).)

Background: New regenerative treatments have emerged with the use of multipotent mesenchymal cells, with special interest in adipose-derived stem cells (ADSCs). In recent years, studies that have sought to identify possible quantitative or qualitative differences in ADSCs derived from different donor subcutaneous adipose tissue have shown divergent results making the determination of a preferential donor area still considered inconclusive., Materials and Methods: The number of ADSCs present in the adipose tissue collected by liposuction was quantified between five different body areas from 17 women, by means of the CFU-F assay and to investigate possible qualitative differences in the ADSCs from these different areas by analyzing: cell surface markers, cell kinetics, action of the supernatant produced by ADSCs from different body areas on fibroblast migration and, finally, differences in the secretome present in the supernatant produced by these cells., Results: The highest mean concentration of CFU-Fs was the dorsum (23.20 ± 26.13), and the lowest was the thighs (6.87 ± 5.04). No qualitative differences were observed in the expression of the cell surface markers or in cell kinetics. Supernatants produced by the ADSCs derived from the abdomen and the thighs demonstrated an increased rate of migration of fibroblasts in vitro similarly. No differences were observed in the secretome between the ADSCs groups., Conclusions: It was observed that the region of the dorsal upper back presented a greater number of ADSCs than the thighs. No qualitative differences were observed between the ADSCs of the five areas analyzed., No Level Assigned: This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Background: Gluteoplasty has gained notoriety over the last decades, which has motivated the development of various surgical techniques. Nevertheless, the fear of dissection of the intramuscular plane without direct visualization may inhibit learning and development of gluteal augmentation with implants. Moreover, literature detailing the technical steps of intramuscular dissection for the construction of the implant pocket is scarce. This study presents a new approach to intramuscular dissection for gluteal augmentation with silicone implants, a variation of the conventional surgical technique., Methods: We performed a retrospective analysis of a series of 12 female patients submitted to a variation of the intramuscular dissection technique for gluteal augmentation with silicone implants. Data from patients, implants, follow-up time, postoperative complications, and the degree of patient satisfaction were obtained. This technique follows the principle of alternating spatulas to perform the blunt dissection of the implant pocket., Results: In this series, the proposed technique is controlled and safe for intramuscular dissection, which can be used for both experienced and training surgeons. This technique is based on well-known anatomical points and references. We observed that the implant was well positioned and covered, the patients were satisfied with the result, and the number of complications was low., Conclusions: This variation of the intramuscular dissection technique for gluteal augmentation with silicone implants provides an easily reproducible and safe procedure that involves well-controlled technical steps, especially during dissection of the intramuscular pocket. In this series of patients, training surgeons learned faster, results were satisfactory, and the number of complications was low., Level of Evidence V: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Purpose: We examined the influence of OGG1 c.977C>G (rs1052133), APEX1 c.444T>G (rs1130409), XRCC1 c.-77T>C (rs3213245), c.580C>T (rs1799782), c.839G>A (rs25489) and c.1196G>A (rs25487) single-nucleotide polymorphisms (SNPs), involved in base-excision repair (BER) pathway, on oropharyngeal squamous cell carcinoma (OPSCC) risk and prognosis., Methods: Aiming to identify the genotypes, DNA from 200 consecutive OPSCC patients and 200 controls was analyzed by PCR-RFLP. The prognostic impact of genotypes of SNPs on progression-free survival (PFS) and overall survival of OPSCC patients was examined using the Kaplan-Meier estimates and Cox regression analyses., Results: XRCC1 c.580CT or TT genotypes (19.5 vs. 11.0 %, P = 0.04) and XRCC1 TTGG haplotype from c.-77T>C, c.580C>T, c.839G>A and c.1196G>A SNPs (17.5 vs. 10.0 %, P = 0.04) were more common in patients with OPSCC than in controls. Carriers of combined genotypes of c.580C>T and TTGG haplotype of XRCC1 gene were under 3.35- and 3.22-fold increased risk of OPSCC than others. For survival analysis, we selected only patients with tumor at stage IV. The median follow-up time was 24.5 months. At 24 months of follow-up, PFS was shorter in patients with OGG1 c.977CC genotype when compared with others genotypes (35.5 vs. 52.1 %, log-rank test, P = 0.03). After multivariate Cox analysis, patients with OGG1 c.977CC genotype had more chance to present tumor progression when compared with others (HR 1.68, P = 0.02)., Conclusions: Our data present, for the first time, evidence that inherited OGG1 c.977C>G; XRCC1 c.-77T>C, c.580C>T, c.839G>A and c.1196G>A abnormalities of DNA BER pathway are important determinants of OPSCC and predictors of patient outcomes.

Background: Oral isotretinoin is increasingly being used to treat acne and other dermatological conditions. The number of patients who take isotretinoin and wish or need to undergo plastic surgery may be following a similar pattern. Although skin healing is an important concern in the case of patients who use isotretinoin, it is definitely not the only relevant issue when planning surgical intervention., Methods: Eleven important points regarding surgery safety in patients taking oral isotretinoin were defined. A literature search of the PubMed database was conducted by employing the keywords isotretinoin OR 13-cis-retinoic acid. This returned the largest possible number of studies about isotretinoin., Results: Forty-seven studies matched the selection criteria. Most animal experimental models suggested that isotretinoin at doses commonly used to treat acne is not detrimental to wound healing. Human studies are controversial. However, healing of skeletal muscle could be at increased risk of necrosis., Conclusions: Association between isotretinoin and problematic skin healing after surgery is being challenged. Also, recommended time between discontinuation of isotretinoin and surgery should be reviewed. While muscle flaps may be endangered in patients taking isotretinoin, healing of other tissues and systemic effects that could compromise surgery safety are rare or detectable before surgery., Level of Evidence V: This journal requires that the authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

Introduction: Angiogenesis (AG) is essential for epithelial ovarian cancer (EOC) development. Vascular endothelial growth factor (VEGF), encoded by the VEGF gene, and endostatin, the product of the COL18A1 gene, act as a potent promoter and an inhibitor of AG, respectively. In the present study, we tested whether VEGF C936T and COL18A1 D104N polymorphisms alter the risk of EOC., Methods: Genomic DNA from 131 EOC patients and 137 controls were analyzed by polymerase chain reaction and restriction fragment length polymorphism methods. The differences between groups were analyzed by χ (2) or Fisher's exact test and logistic regression analysis., Results: The frequency of the VEGF 936CC genotype was higher in patients than in controls (84.8% vs. 75.3%, P = 0.03). Individuals with respective genotypes had a 1.98 (95% CI 1.04-3.78)-fold increased risk of EOC than those with the remaining genotypes. An excess of VEGF 936CC plus COL18A1 DN genotype was seen in patients when compared to controls (48.6% vs. 30.5%); however, only a tendency toward a statistically significant difference in genotype frequencies was found in the study (P = 0.06), reflecting a trend toward an increased risk of 2.44 for EOC in carriers of the combined genotype., Conclusion: Our data present, for the first time, preliminary evidence that VEGF C936T alone or combined with the COL18A1 D104N polymorphism of AG constitutes an important inherited EOC determinant.

Purpose: We examined the influence of XPC A2920C, XPF T30028C, TP53 Arg72Pro and GSTP1 Ile105Val polymorphisms in the risk of cutaneous melanoma (CM)., Methods: DNA from 146 CM patients and 146 controls was analysed by polymerase chain reaction (PCR)--restriction fragment length polymorphism (RFLP)., Results: The frequencies of XPC CC (15.1 vs. 6.9 %, P = 0.02), TP53 ArgArg (59.6 vs. 45.9 %, P = 0.02), XPC CC plus TP53 ArgArg (19.7 vs. 5.2 %, P = 0.01) and TP53 ArgArg plus GSTP1 IleIle (50.7 vs. 35.6 %, P = 0.03) genotypes were higher in patients than in controls. Carriers of the respective genotypes were under a 2.51 (95 % CI: 1.13-5.55), 1.76 (95 % CI: 1.09-2.83), 4.52 (95 % CI: 1.35-15.16), and 2.01 (95 % CI: 1.04-3.90)-fold increased risks for CM than others, respectively. An excess of TP53 ArgArg genotype was seen in patients with excessive sun exposure compared to patients with standard sun exposure (69.2 vs. 44.1 %, P = 0.02) and also compared to controls (69.2 vs. 45.9 %, P = 0.002). Individuals with TP53 ArgArg genotype and highly exposed to sunlight had 2.65 (95 % CI: 1.42-4.92)-fold increased risk for CM than others. XPC CC (27.8 vs. 10.4 %, P = 0.02) and the GSTP1 IleIle (58.3 vs. 36.8 %, P = 0.04) genotypes were more common in patients with advanced tumours than in patients with localized tumours and were also more common in these patients than in controls (27.8 vs. 6.9 %, P = 0.001; 58.3 vs. 37.0 %, P = 0.02, respectively). Individuals with the respective genotypes had 5.23 (95 % CI: 1.97-13.82)-fold and 2.38 (95 % CI: 1.13-5.01)-fold increased risks for advanced tumour than others, respectively., Conclusion: Our data suggest that inherited abnormalities of XPC, XPF, TP53 and GSTP1 pathways of the DNA repair, apoptosis and metabolism of reactive oxygen species are important determinants of CM in individuals from south-eastern Brazil.