Marine and Agro-Industrial By-Products Valorization Intended for Topical Formulations in Wound Healing Applications

Over the past years, research attention has been focusing more on waste-derived, naturally derived, and renewable materials, in the view of a more sustainable economy. In this work, different topical formulations were obtained from the valorization of marine and agro-industrial by-products and the use of Carbopol 940 as gelling agent. In particular, the combination of extracts obtained from the marine snail, Rapanosa venosa, with Cladophora vagabunda and grape pomace extracts, was investigated for wound healing purposes. Rapana venosa has demonstrated wound healing properties and antioxidant activity. Similarly, grape pomace extracts have been shown to accelerate the healing process. However, their synergic use has not been explored yet. To this aim, four different formulations were produced. Three formulations differed for the presence of a different extract of Rapana venosa: marine collagen, marine gelatin, and collagen hydrolysate, while another formulation used mammalian gelatin as further control. Physico-chemical properties of the extracts as well as of the formulations were analyzed. Furthermore, thermal stability was evaluated by thermogravimetric analysis. Antioxidant capacity and biological behavior, in terms of cytocompatibility, wound healing, and antimicrobial potential, were assessed. The results highlighted for all the formulations (i) a good conservation and thermal stability in time, (ii) a neutralizing activity against free radicals, (iii) and high degree of cytocompatibility and tissue regeneration potential. In particular, collagen, gelatin, and collagen hydrolysate obtained from the Rapana venosa marine snail represent an important, valuable alternative to mammalian products.     

Antinociceptive and anti-inflammatory activities of Bowdichia virgilioides (sucupira)

Ethnopharmacological relevance

Bowdichia virgilioides Kunth (Leguminosae Papilonoideae) is a plant with anti-inflammatory activity used in folk medicine. The importance of this plant promoted its inclusion in Brazilian Pharmacopoeia.

Aim of the study

In order to evaluate the actions of this plant, studies were performed on antinociceptive and anti-inflammatory activities.

Materials and methods

The aqueous extracts (AE) of Bowdichia virgilioides inner bark and leaves were used at 100, 200, and 400 mg/kg. Antinociceptive activity of plant extract was evaluated by writhing, hot-plate and formalin tests. Anti-inflammatory activity was evaluated using paw oedema and peritonitis methods.

Results

Oral treatment with the AE of inner bark or leaves elicited inhibitory activity (P < 0.01) on acetic acid effect at 200 and 400 mg/kg, and reduced the formalin effect at the second-phase (200 and 400 mg/kg, P < 0.01), however it did not elicit any inhibitory effect on hot-plate test. The indomethacin inhibited the acetic acid-induced writhing and the formalin effect at the second-phase (P < 0.001), and the morphine reduced the both phases of formalin test (P < 0.001). Carrageenan-induced oedema formation and neutrophil migration into the peritoneal cavity were reduced with the AE of inner bark or leaves at 100, 200, and 400 mg/kg (P < 0.05), and by the reference compounds aspirin (P < 0.001) and dexamethasone (P < 0.001), respectively.

Conclusions

The AE of Bowdichia virgilioides shows antinociceptive and anti-inflammatory activities, supporting the folkloric usage of the plant to treat various inflammatory diseases.     

Evaluation of the Biocompatibility and Osteogenic Properties of Metal Oxide Coatings Applied by Magnetron Sputtering as Potential Biofunctional Surface Modifications for Orthopedic Implants

Biomaterials with adequate properties to direct a biological response are essential for orthopedic and dental implants. The surface properties are responsible for the biological response; thus, coatings with biologically relevant properties such as osteoinduction are exciting options to tailor the surface of different bulk materials. Metal oxide coatings such as TiO₂, ZrO₂, Nb₂O₅ and Ta₂O₅ have been suggested as promising for orthopedic and dental implants. However, a comparative study among them is still missing to select the most promising for bone-growth-related applications. In this work, using magnetron sputtering, TiO₂, ZrO₂, Ta₂O₅, and Nb₂O₅ thin films were deposited on Si (100) substrates. The coatings were characterized by Optical Profilometry, Scanning Electron Microscopy, Energy-Dispersive X-ray Spectroscopy, X-ray Photoelectron Spectroscopy, X-ray Diffraction, Water Contact Angle measurements, and Surface Free Energy calculations. The cell adhesion, viability, proliferation, and differentiation toward the osteoblastic phenotype of mesenchymal stem cells plated on the coatings were measured to define the biological response. Results confirmed that all coatings were biocompatible. However, a more significant number of cells and proliferative cells were observed on Nb₂O₅ and Ta₂O₅ compared to TiO₂ and ZrO_2. Nevertheless, Nb₂O₅ and Ta₂O₅ seemed to induce cell differentiation toward the osteoblastic phenotype in a longer cell culture time than TiO₂ and ZrO₂.     

Impact of registration on clinical trials on infection risk in pediatric acute myeloid leukemia

Little is known about the impact of enrollment on therapeutic clinical trials on adverse event rates. Primary objective was to describe the impact of clinical trial registration on sterile site microbiologically documented infection for children with newly diagnosed acute myeloid leukemia (AML). We conducted a multicenter cohort study that included children aged ≤18 years with de novo AML. Primary outcome was microbiologically documented sterile site infection. Infection rates were compared between those registered and not registered on clinical trials. Five hundred seventy‐four children with AML were included of which 198 (34.5%) were registered on a therapeutic clinical trial. Overall, 400 (69.7%) had at least one sterile site microbiologically documented infection. In multiple regression, registration on clinical trials was independently associated with a higher risk of microbiologically documented sterile site infection [adjusted odds ratio (OR) 1.24, 95% confidence interval (CI) 1.01–1.53; p = 0.040] and viridans group streptococcal infection (OR 1.46, 95% CI 1.08–1.98; p = 0.015). Registration on trials was not associated with Gram‐negative or invasive fungal infections. Children with newly diagnosed AML enrolled on clinical trials have a higher risk of microbiologically documented sterile site infection. This information may impact on supportive care practices in pediatric AML.     

Emergency obstetric hysterectomy

BACKGROUND: All cases of obstetric hysterectomies that were performed in our hospital during a seven-year study period were reviewed in order to evaluate the incidence, indications, risk factors, and complications associated with emergency obstetric hysterectomy. METHODS: Medical records of 45 patients who had undergone emergency hysterectomy were scrutinized and evaluated retrospectively. Maternal age, parity, gestational age, indication for hysterectomy, the type of operation performed, estimated blood loss, amount of blood transfused, complications, and hospitalization period were noted and evaluated. The main outcome measures were the factors associated with obstetric hysterectomy as well as the indications for the procedure. RESULTS: During the study period there were 32,338 deliveries and 9,601 of them (29.7%) were by cesarean section. In this period, 45 emergency hysterectomies were performed, with an incidence of 1 in 2,526 vaginal deliveries and 1 in 267 cesarean sections. All of them were due to massive postpartum hemorrhage. The most common underlying pathologies was placenta accreta (51.1%) and placenta previa (26.7%). There was no maternal mortality. CONCLUSIONS: Obstetric hysterectomy is a necessary life-saving procedure. Abnormal placentation is the leading cause of emergency hysterectomy when obstetric practice is characterized by a high cesarean section rate. Therefore, every attempt should be made to reduce the cesarean section rate by performing this procedure only for valid clinical indications.     

Morphologic,endocrinologic and natural pregnancy assessment of allogeneic ovarian orthotopic transplantation without a vascular pedicle in rabbits

Objective

The objective was to assess the natural pregnancy of rabbits subjected to bilateral oophorectomy and orthotopic allogeneic intact and sliced ovarian transplantation without a vascular pedicle, and to determine the morphofunctional aspects of the transplanted ovaries.

Study design

Thirty-two female rabbits were studied. The ovaries were removed and orthotopically transplanted without vascular anastomoses between the two breeds of rabbits. In Group 1 (n = 8), only laparotomy and laparorrhaphy were performed, in Group 2A (n = 8) intact ovaries were transplanted on both sides, in Group 2B (n = 8) both ovaries were sliced and orthotopically transplanted, and in Group 2C (n = 8) an intact ovary was transplanted on one side and a sliced ovary on the other side. Three months later, the animals were paired with males for copulation. Estradiol, progesterone, follicle-stimulating hormone, and luteinizing hormone levels were assessed. A histologic study was carried out and the numbers of pregnancies and litters were also determined.

Results

Pregnancies occurred in seven rabbits in Group 1, 37.5% of rabbits in Group 2A, 50% in Group 2B, and 62.5% in Group 2C. Hormone levels and histology confirmed the vitality and function of all ovaries.

Conclusions

Intact or sliced orthotopic allogeneic ovarian transplantation without a vascular pedicle is viable in rabbits, and preserves their hormonal and fertile functions.     

Resistance Exercise Training Improves Metabolic and Inflammatory Control in Adipose and Muscle Tissues in Mice Fed a High-Fat Diet

This study investigates whether ladder climbing (LC), as a model of resistance exercise, can reverse whole-body and skeletal muscle deleterious metabolic and inflammatory effects of high-fat (HF) diet-induced obesity in mice. To accomplish this, Swiss mice were fed for 17 weeks either standard chow (SC) or an HF diet and then randomly assigned to remain sedentary or to undergo 8 weeks of LC training with progressive increases in resistance weight. Prior to beginning the exercise intervention, HF-fed animals displayed a 47% increase in body weight (BW) and impaired ability to clear blood glucose during an insulin tolerance test (ITT) when compared to SC animals. However, 8 weeks of LC significantly reduced BW, adipocyte size, as well as glycemia under fasting and during the ITT in HF-fed rats. LC also increased the phosphorylation of Akt_Ser473 and AMPK_Thr172 and reduced tumor necrosis factor-alpha (TNF-α) and interleukin 1 beta (IL1-β) contents in the quadriceps muscles of HF-fed mice. Additionally, LC reduced the gene expression of inflammatory markers and attenuated HF-diet-induced NADPH oxidase subunit gp91phox in skeletal muscles. LC training was effective in reducing adiposity and the content of inflammatory mediators in skeletal muscle and improved whole-body glycemic control in mice fed an HF diet.     

Gene evolutionary trajectories in Mycobacterium tuberculosis reveal temporal signs of selection

Genetic differences between different Mycobacterium tuberculosis complex (MTBC) strains determine their ability to transmit within different host populations, their latency times, and their drug resistance profiles. Said differences usually emerge through de novo mutations and are maintained or discarded by the balance of evolutionary forces. Using a dataset of ∼5,000 strains representing global MTBC diversity, we determined the past and present selective forces that have shaped the current variability observed in the pathogen population. We identified regions that have evolved under changing types of selection since the time of the MTBC common ancestor. Our approach highlighted striking differences in the genome regions relevant for host–pathogen interaction and, in particular, suggested an adaptive role for the sensor protein of two-component systems. In addition, we applied our approach to successfully identify potential determinants of resistance to drugs administered as second-line tuberculosis treatments.

The Mycobacterium tuberculosis complex (MTBC) is a genetically monomorphic group of bacteria (1, 2) whose members cause tuberculosis in humans and animals. The MTBC comprises both human-associated (L1, L2, L3, L4, L5, L6, L7, L8, and L9) and animal-associated (A1, A2, A3, and A4) clades (3–7). Due to the absence of horizontal gene transfer, plasmids, and measurable recombination among strains and other species (8–10), chromosomal mutations represent the source of MTBC genetic diversity. The maximum genetic distance between any two MTBC strains is around 2,500 single-nucleotide polymorphisms (SNPs). Strikingly, studies have highlighted large phenotypic differences between strains involving traits like gene expression, drug resistance, transmissibility, and immune response, despite this limited variation. In some cases, the mutations driving phenotypic differences have been identified—for example, nonsynonymous variants in genes, such as rpoB, katG, or gyrA, cause drug-resistant phenotypes (11–13). Furthermore, single mutations in regulatory elements can induce alterations to downstream gene expression, which can foster differential virulence characteristics (14, 15). Finally, specific gene mutations may affect transmission (9), host tropism within the complex (16), and the host immune response (17). However, many of the genomic determinants of these phenotypes remain elusive, despite robust evidence that they are driven by genetic differences between strains (18, 19).Several types of evolutionary forces play crucial roles in the fixation of mutations in bacterial populations. Previous research has provided evidence for the ongoing positive selection of specific genes and regions (9, 20–23), while other studies have reported ongoing purifying selection of specific genomic regions, especially in epitopes and essential genes (24). Additionally, there exists some evidence that genetic drift may have significant functional and evolutionary consequences (25).Detecting selection in MTBC at the genome-wide level remains a challenging task due to limited genetic diversity. The significant accumulation of nonsynonymous substitutions has been previously used to characterize patterns of mutation accumulation in large categories of genes (24, 26); however, these studies employed a limited number of strains. Of note, the number of MTBC sequences has undergone a recent and rapid expansion, with studies involving hundreds to thousands of strains. The large number of available sequences has allowed, for example, the estimation of the ratio of nonsynonymous to synonymous substitutions (dN/dS) signatures in more than 10,000 strains (27), thereby allowing the identification of targets of selection with some probably related to host–pathogen interactions. Host–pathogen interaction signals are specially challenging as they are likely obscured by the force exerted by antimicrobial therapies. Weaker signals are also expected in genes related to second-line drugs related to the relative underuse of related treatments and the low abundance of associated resistant strains in genome databases (28).We reasoned that to detect signs of selection, we should focus on when and/or where they occurred in the phylogenetic tree instead of averaging signs across the phylogeny. In this study, we developed a methodology to study temporal signs of selection in MTBC genes and identified positive selection in a larger number of genes than previously described. This allowed the identification of past and currently unknown players in the MTBC evolution, particularly two-component systems (2CSs), related to host adaptation and second-line drug resistance. This methodology can be applied to other tuberculosis settings to explore signs of selection associated with changing selective pressures and could be extremely useful to unravel hidden details in the evolution of other human pathogens.     

Efficacy of a spatial repellent for control of Aedes-borne virus transmission: A cluster-randomized trial in Iquitos,Peru

Over half the world’s population is at risk for viruses transmitted by Aedes mosquitoes, such as dengue and Zika. The primary vector, Aedes aegypti, thrives in urban environments. Despite decades of effort, cases and geographic range of Aedes-borne viruses (ABVs) continue to expand. Rigorously proven vector control interventions that measure protective efficacy against ABV diseases are limited to Wolbachia in a single trial in Indonesia and do not include any chemical intervention. Spatial repellents, a new option for efficient deployment, are designed to decrease human exposure to ABVs by releasing active ingredients into the air that disrupt mosquito–human contact. A parallel, cluster-randomized controlled trial was conducted in Iquitos, Peru, to quantify the impact of a transfluthrin-based spatial repellent on human ABV infection. From 2,907 households across 26 clusters (13 per arm), 1,578 participants were assessed for seroconversion (primary endpoint) by survival analysis. Incidence of acute disease was calculated among 16,683 participants (secondary endpoint). Adult mosquito collections were conducted to compare Ae. aegypti abundance, blood-fed rate, and parity status through mixed-effect difference-in-difference analyses. The spatial repellent significantly reduced ABV infection by 34.1% (one-sided 95% CI lower limit, 6.9%; one-sided P value = 0.0236, z = 1.98). Aedes aegypti abundance and blood-fed rates were significantly reduced by 28.6 (95% CI 24.1%, ∞); z = −9.11) and 12.4% (95% CI 4.2%, ∞); z = −2.43), respectively. Our trial provides conclusive statistical evidence from an appropriately powered, preplanned cluster-randomized controlled clinical trial of the impact of a chemical intervention, in this case a spatial repellent, to reduce the risk of ABV transmission compared to a placebo.

Aedes-borne viral diseases (ABVDs) [e.g., dengue (DENV), chikungunya, Zika (ZIKV), and yellow fever] are devastating, expanding global public health threats that disproportionally affect low- and middle-income countries. DENV, one of the most rapidly increasing vector-borne infectious diseases, results in ∼400 million infections each year (1, 2), with 4 billion people at risk for infection annually (3). Currently, the primary means for ABVD prevention is controlling the primary mosquito vector, Aedes aegypti. Existing vector control interventions, however, have failed to prevent ABV transmission and epidemics (4–6).There is an urgent need to develop evidence-based guidance for the use of new and existing ABV vector control tools. The evidence base for vector control against ABVs is weak, despite considerable government investments in World Health Organization (WHO)-recommended control of larval habitats (larviciding, container removal) and ultra-low-volume insecticide spraying (4, 5, 7–9). These strategies continue to be implemented despite the lack of rigorously generated data from controlled clinical trials demonstrating they reduce ABV infection or disease (6). The only ABV intervention with a proven epidemiological impact in a cluster-randomized control trial (cRCT) assessed community mobilization to reduce mosquito larval habitats (10). A recent test-negative trial with Wolbachia-infected mosquitoes reported a significant reduction of DENV illness in Indonesia (11).Spatial repellents (SRs) are devices that contain volatile active ingredients that disperse in air. The active ingredients can repel mosquitoes from entering a treated space, inhibit attraction to human host cues, or disrupt mosquito biting and blood-feeding behavior and, thus, interfere with mosquito–human contact (12–14). Any of these outcomes reduce the probability of pathogen transmission. Pyrethroid-based SRs have shown efficacy in reducing malaria infections in China (15) and Indonesia (16). There have, however, been no clinical trials evaluating the protective efficacy (PE) of SRs against ABV infection or disease.To generate evidence for public health consideration, we conducted a double-blinded, parallel cRCT to demonstrate and quantify the PE of a transfluthrin-based SR to reduce ABV infection incidence over 2 y in a human cohort in Iquitos, Peru.