No abstract

BackgroundAntibiotic-associated diarrhea (AAD) is a risk factor for exacerbating the outcome of critically ill patients. Dysbiosis induced by the exposure to antibiotics reveals the potential therapeutic role of fecal microbiota transplantation (FMT) in these patients. Herein, we aimed to evaluate the safety and potential benefit of rescue FMT for AAD in critically ill patients.MethodsA series of critically ill patients with AAD received rescue FMT from Chinese fmtBank, from September 2015 to February 2019. Adverse events (AEs) and rescue FMT success which focused on the improvement of abdominal symptoms and post-ICU survival rate during a minimum of 12 weeks follow-up were assessed.ResultsTwenty critically ill patients with AAD underwent rescue FMT, and 18 of them were included for analysis. The mean of Acute Physiology and Chronic Health Evaluation (APACHE) II scores at intensive care unit (ICU) admission was 21.7 ± 8.3 (range 11–37). Thirteen patients received FMT through nasojejunal tube, four through gastroscopy, and one through enema. Patients were treated with four (4.2 ± 2.1, range 2–9) types of antibiotics before and during the onset of AAD. 38.9% (7/18) of patients had FMT-related AEs during follow-up, including increased diarrhea frequency, abdominal pain, increased serum amylase, and fever. Eight deaths unrelated to FMT occurred during follow-up. One hundred percent (2/2) of abdominal pain, 86.7% (13/15) of diarrhea, 69.2% (9/13) of abdominal distention, and 50% (1/2) of hematochezia were improved after FMT. 44.4% (8/18) of patients recovered from abdominal symptoms without recurrence and survived for a minimum of 12 weeks after being discharged from ICU.ConclusionIn this case series studying the use of FMT in critically ill patients with AAD, good clinical outcomes without infectious complications were observed. These findings could potentially encourage researchers to set up new clinical trials that will provide more insight into the potential benefit and safety of the procedure in the ICU.Trial registrationClinicalTrials.gov, Number NCT03895593. Registered 29 March 2019 (retrospectively registered).

No abstract

Background β-Tricalcium phosphate (β-TCP) is one of the most common synthetic bone grafting materials utilized in craniofacial reconstruction; however, it is limited by a slow degradation rate. The aim of this study was to leverage 3-dimensional (3D) printing in an effort to accelerate the degradation kinetics of β-TCP. Methods Twenty-two 1-month-old New Zealand white rabbits underwent creation of calvarial and alveolar defects, repaired with 3D-printed β-TCP scaffolds coated with 1000 μM of osteogenic agent dipyridamole. Rabbits were euthanized after 2, 6, and 18 months after surgical intervention. Bone regeneration, scaffold degradation, and bone mechanical properties were quantified. Results Histological analysis confirmed the generation of vascularized and organized bone. Microcomputed tomography analysis from 2 to 18 months demonstrated decreased scaffold volume within calvarial (23.6% ± 2.5%, 5.1% ± 2.2%; P < 0.001) and alveolar (21.5% ± 2.2%, 0.2% ± 1.9%; P < 0.001) defects, with degradation rates of 54.6%/year and 90.5%/year, respectively. Scaffold-inducted bone generation within the defect was volumetrically similar to native bone in the calvarium (55.7% ± 6.9% vs 46.7% ± 6.8%; P = 0.064) and alveolus (31.4% ± 7.1% vs 33.8% ± 3.7%; P = 0.337). Mechanical properties between regenerated and native bone were similar. Conclusions Our study demonstrates an improved degradation profile and replacement of absorbed β-TCP with vascularized, organized bone through 3D printing and addition of an osteogenic agent. This novel additive manufacturing and tissue engineering protocol has implications to the future of craniofacial skeletal reconstruction as a safe and efficacious bone tissue engineering method.

left lip and palate are the most common congenital anomaly of the face. Although the optimal indications and treatment protocols continue to be debated, one of the most actively discussed therapies is nasoalveolar molding. [1][2][3] Supporters of nasoalveolar molding cite statistically significant improvements in nasal symmetry in patients who undergo the treatment compared with those who do not, 4,5 benefit to nasal aesthetics as judged by caregivers and surgeons, 6,7 greater benefit to columellar length in patients with bilateral cleft lip, 8-10 cost benefit compared with lip adhesion, 11 decreased need for revision surgery on the nose, 9,12 psychosocial benefit to caregivers, 6,7 and the opportunity for primary alveolar reconstruction in the form of gingivoperiosteoplasty, which can avoid secondary alveolar bone

The thermal contraction of aqueous cryoprotectant solutions on cooling to cryogenic temperatures is of practical importance in protein cryocrystallography and in biological cryopreservation. In the former case, differential contraction on cooling of protein molecules and their lattice relative to that of the internal and surrounding solvent may lead to crystal damage and the degradation of crystal diffraction properties. Here, the amorphous phase densities of aqueous solutions of glycerol and ethylene glycol at T = 77 K have been determined. Densities with accuracies of <0.5% to concentrations as low as 30%(w/v) were determined by rapidly cooling drops with volumes as small as 70 pl, assessing their optical clarity and measuring their buoyancy in liquid nitrogen-argon solutions. The use of these densities in contraction matching of internal solvent to the available solvent spaces is complicated by several factors, most notably the exclusion of cryoprotectants from protein hydration shells and the expected deviation of the contraction behavior of hydration water from bulk water. The present methods and results will assist in developing rational approaches to cryoprotection and an understanding of solvent behavior in protein crystals.

Background: Three-dimensional printed bioceramic scaffolds composed of 100% β-tricalcium phosphate augmented with dipyridamole (3DPBC-DIPY) can regenerate bone across critically sized defects in skeletally mature and immature animal models. Before human application, safe and effective bone formation should be demonstrated in a large translational animal model. This study evaluated the ability of 3DPBC-DIPY scaffolds to restore critically sized calvarial defects in a skeletally immature, growing minipig. Methods: Unilateral calvarial defects (~1.4 cm) were created in 6-week-old Göttingen minipigs (n = 12). Four defects were filled with a 1000 μm 3DPBC-DIPY scaffold with a cap (a solid barrier on the ectocortical side of the scaffold to prevent soft-tissue infiltration), four defects were filled with a 1000 μm 3DPBC-DIPY scaffold without a cap, and four defects served as negative controls (no scaffold). Animals were euthanized 12 weeks postoperatively. Calvariae were subjected to micro–computed tomography, 3D reconstruction with volumetric analysis, qualitative histologic analysis, and nanoindentation. Results: Scaffold-induced bone growth was statistically greater than in negative controls (P ≤ 0.001), and the scaffolds with caps produced significantly more bone generation compared with the scaffolds without caps (P ≤ 0.001). Histologic analysis revealed woven and lamellar bone with haversian canals throughout the regenerated bone. Cranial sutures were observed to be patent, and there was no evidence of ectopic bone formation or excess inflammatory response. Reduced elastic modulus and hardness of scaffold-regenerated bone were found to be statistically equivalent to native bone (P = 0.148 for reduced elastic modulus of scaffolds with and without caps and P = 0.228 and P = 0.902 for hardness of scaffolds with and without caps, respectively). Conclusion: 3DPBC-DIPY scaffolds have the capacity to regenerate bone across critically sized calvarial defects in a skeletally immature translational pig model. Clinical Relevance Statement: This study assessed the bone generative capacity of 3D-printed bioceramic scaffolds composed of 100% β-tricalcium phosphate and augmented with dipyridamole placed within critical-sized calvarial defects in a growing porcine model.

Crystal formation obtained from evaporating clear filtrates of dental stone mixed with various solutions were examined with an optical and scanning electron microscope. It was found that when K2SO4 was present in any concentration, a spherulitic structure dissimilar to that of CaSO4. 2H2O and K2SO4 was dominant. It is concluded that syngenite (a complex compound of CaSO4 and K2SO4) forms at the center of the nuclei of crystallization and is responsible for spherulitic formation. The use of K2SO4 solution and saturated CaSO4 solution was also found to improve the strength both at one and 24 h.