Targeted Mutations in the Fusion Peptide Region of La Crosse Virus Attenuate Neuroinvasion and Confer Protection against Encephalitis

La Crosse virus (LACV) is a major cause of pediatric encephalitis and aseptic meningitis in the Midwestern, Mid-Atlantic, and Southern United States, where it is an emerging pathogen. The LACV Gc glycoprotein plays a critical role in the neuropathogenesis of LACV encephalitis as the putative virus attachment protein. Previously, we identified and experimentally confirmed the location of the LACV fusion peptide within Gc and generated a panel of recombinant LACVs (rLACVs) containing mutations in the fusion peptide as well as the wild-type sequence. These rLACVs retained their ability to cause neuronal death in a primary embryonic rat neuronal culture system, despite decreased replication and fusion phenotypes. To test the role of the fusion peptide in vivo, we tested rLACVs in an age-dependent murine model of LACV encephalitis. When inoculated directly into the CNS of young adult mice (P28), the rLACV fusion peptide mutants were as neurovirulent as the rLACV engineered with a wild-type sequence, confirming the results obtained in tissue culture. In contrast, the fusion peptide mutant rLACVs were less neuroinvasive when suckling (P3) or weanling (P21) mice were inoculated peripherally, demonstrating that the LACV fusion peptide is a determinant of neuroinvasion, but not of neurovirulence. In a challenge experiment, we found that peripheral challenge of weanling (P21) mice with fusion peptide mutant rLACVs protected from a subsequent WT-LACV challenge, suggesting that mutations in the fusion peptide are an attractive target for generating live-attenuated virus vaccines. Importantly, the high degree of conservation of the fusion peptide amongst the Bunyavirales and, structurally, other arboviruses suggests that these findings are broadly applicable to viruses that use a class II fusion mechanism and cause neurologic disease.     

Influence of Xenogeneic and Alloplastic Carriers for Bone Augmentation on Human Unrestricted Somatic Stem Cells

Alloplastic and xenogeneic bone grafting materials are frequently used for bone augmentation. The effect of these materials on precursor cells for bone augmentation is yet to be determined. The aim of this study was to ascertain, in vitro, how augmentation materials influence the growth rates and viability of human unrestricted somatic stem cells. The biocompatibility of two xenogeneic and one alloplastic bone graft was tested using human unrestricted somatic stem cells (USSCs). Proliferation, growth, survival and attachment of unrestricted somatic stem cells were monitored after 24 h, 48 h and 7 days. Furthermore, cell shape and morphology were evaluated by SEM. Scaffolds were assessed for their physical properties by Micro-CT imaging. USSCs showed distinct proliferation on the different carriers. Greatest proliferation was observed on the xenogeneic carriers along with improved viability of the cells. Pore sizes of the scaffolds varied significantly, with the xenogeneic materials providing greater pore sizes than the synthetic inorganic material. Unrestricted somatic stem cells in combination with a bovine collagenous bone block seem to be very compatible. A scaffold’s surface morphology, pore size and bioactive characteristics influence the proliferation, attachment and viability of USSCs.     

Probiotics Administration in Cystic Fibrosis: What Is the Evidence?

In the last 20 years, gut microbiota in patients with cystic fibrosis (CF) has become an object of interest. It was shown that these patients had gut dysbiosis and this could explain not only the intestinal manifestations of the disease but also part of those involving the respiratory tract. The acquisition of previously unknown information about the importance of some bacteria, i.e., those partially or totally disappeared in the gut of CF patients, in the regulation of the activity and function of the gut and the lung was the base to suggest the use of probiotics in CF patients. The main aim of this paper is to discuss the biological basis for probiotic administration to CF patients and which results could be expected. Literature analysis showed that CF intestinal dysbiosis depends on the same genetic mutations that condition the clinical picture of the diseases and is aggravated by a series of therapeutic interventions, such as dietary modifications, the use of antibiotics, and the administration of antacids. All this translates into a significant worsening of the structure and function of organs, including the lung and intestine, already deeply penalized by the genetic alterations of CF. Probiotics can intervene on dysbiosis, reducing the negative effects derived from it. However, the available data cannot be considered sufficient to indicate that these bacteria are essential elements of CF therapy. Further studies that take into account the still unsolved aspects on how to use probiotics are absolutely necessary.     

An open-label, multicentre trial to evaluate the vaginal bleeding pattern of the combined contraceptive vaginal ring NuvaRing

Objective

The objective of this multicentre, non-controlled, open-label study is the evaluation of the bleeding patterns during the use of a vaginal combined contraceptive, its safety in relation to occurrence of adverse effects, its efficacy as a contraceptive method and user compliance.

Study design

Healthy female volunteers (N = 165), asking for contraception, were enrolled to participate in the study. Each subject was given seven vaginal rings, releasing an average amount of 120 μg etonogestrel (ENG) and 15 μg ethinylestradiol (EE) per day. Study period was 7 cycles. A total of 878 cycles was valid for statistical analysis. The primary parameter, (breakthrough bleeding and/or spotting), was recorded for each cycle. The subjects were asked to report any adverse effect experienced during the treatment period, general physical and gynaecological examinations were performed and haematological blood tests were taken.

Results

Breakthrough bleeding/spotting occurred in 5.01% cycles (44 out of 878 cycles, of whom 37 were breakthrough spotting only). Absence of withdrawal bleeding during the ring-free period was reported in 1.94% cycles (17 out of 878). Forty-one subjects (24.8%) reported 66 events that were potentially drug-related. The most frequently drug-related events were weight increase (10 cases), headache (9 cases), nausea (4 cases). No pregnancy was reported during the study period. Haematology and chemical chemistry tests showed no clinically significant abnormality.

Conclusions

In the present study, NuvaRing^® has shown to be a valid contraceptive method to ensure optimal cycle control with low incidence of irregular bleeding and altered withdrawal bleeding. The low incidence of gastrointestinal side effects (nausea, vomiting) may be related the low hormonal dose and to the vaginal delivery of hormones which avoids the gastrointestinal tract.     

Impact of oncostatic treatments for childhood malignancies (radiotherapy and chemotherapy) on uterine competence to pregnancy

Fertility preservation in young girls affected by malignancies has got growing relevance in the last decade due to the improved survival chance of these patients after oncostatic treatments. Most studies have focused on preserving ovarian follicles and avoiding premature ovarian failure, whereas only a few have evaluated the effects exerted by radiotherapy and chemotherapy on the uterus. It is self-evident that fertility preservation after oncostatic therapies must include the maintenance of a functional uterus, and a certain degree of uterine damage must be considered when estimating reproductive prognosis in previously treated, childhood cancer survivors. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to recall the growing number of children who survive oncostatic treatments, explain the possible effects on future reproductive endeavors, and summarize the possible ways to preserve fertility.     

Inherited thrombophilias and pre-eclampsia in Brazilian women

OBJECTIVE: The aim of the present study was to compare the distribution of G1691A, G20210A and C677T mutations in pre-eclamptic Brazilian women and in matched control women with an uncomplicated normal pregnancy. STUDY DESIGN: these mutations were investigated by PCR-RFLP in 83 normal pregnancies (control group) and in 30 pre-eclamptic pregnant women (severe form). RESULTS: G1691A mutation was detected neither in the control group nor in pre-eclamsia women. G20210A mutation was detected in heterozygosis in 3 (3.61%) control subjects, but not in pre-eclampsia group. C677T mutation was detected in homozygosis in 6 (7.23%) control subjects and 2 (6.67%) pre-eclamptic women and in heterozygosis in 31 (37.3%) control subjects and 12 (40%) pre-eclamptic women. Differences in the mutation frequencies detected in the two groups were not statistically significant. CONCLUSION: No correlation was observed between pre-eclampsia and presence of G1691A, G20210A and C677T mutations in Brazilian women.     

Agar Biopolymer Films for Biodegradable Packaging: A Reference Dataset for Exploring the Limits of Mechanical Performance

This article focuses on agar biopolymer films that offer promise for developing biodegradable packaging, an important solution for reducing plastics pollution. At present there is a lack of data on the mechanical performance of agar biopolymer films using a simple plasticizer. This study takes a Design of Experiments approach to analyze how agar-glycerin biopolymer films perform across a range of ingredients concentrations in terms of their strength, elasticity, and ductility. Our results demonstrate that by systematically varying the quantity of agar and glycerin, tensile properties can be achieved that are comparable to agar-based materials with more complex formulations. Not only does our study significantly broaden the amount of data available on the range of mechanical performance that can be achieved with simple agar biopolymer films, but the data can also be used to guide further optimization efforts that start with a basic formulation that performs well on certain property dimensions. We also find that select formulations have similar tensile properties to thermoplastic starch (TPS), acrylonitrile butadiene styrene (ABS), and polypropylene (PP), indicating potential suitability for select packaging applications. We use our experimental dataset to train a neural network regression model that predicts the Young’s modulus, ultimate tensile strength, and elongation at break of agar biopolymer films given their composition. Our findings support the development of further data-driven design and fabrication workflows.