Currently, the fabrication of a functional vascular network to maintain the viability of engineered tissues is a major bottleneck in the way of developing a more advanced engineered construct. Inspired by vasculogenesis during the embryonic period, the in vitro prevascularization strategies have focused on optimizing communications and interactions of cells, biomaterial and culture conditions to develop a capillary-like network to tackle the aforementioned issue. Many of these studies employ a combination of endothelial lineage cells and supporting cells such as mesenchymal stem cells, fibroblasts, and perivascular cells to create a lumenized endothelial network. These supporting cells are necessary for the stabilization of the newly developed endothelial network. Moreover, to optimize endothelial network development without impairing biomechanical properties of scaffolds or differentiation of target tissue cells, several other factors, including target tissue, endothelial cell origins, the choice of supporting cell, culture condition, incorporated pro-angiogenic factors, and choice of biomaterial must be taken into account. The prevascularization method can also influence the endothelial lineage cell/supporting cell co-culture system to vascularize the bioengineered constructs. This review aims to investigate the recent advances on standard cells used in in vitro prevascularization methods, their co-culture systems, and conditions in which they form an organized and functional vascular network.

Decellularized and de-epithelialized placenta membranes have widely been used as scaffolds and grafts in tissue engineering and regenerative medicine. Exceptional pro-angiogenic and biomechanical properties and low immunogenicity have made the amniochorionic membrane a unique substrate which provides an enriched niche for cellular growth. Herein, an optimized combination of enzymatic solutions (based on streptokinase) with mechanical scrapping is used to remove the amniotic epithelium and chorion trophoblastic layer, which resulted in exposing the basement membranes of both sides without their separation and subsequent damages to the in-between spongy layer. Biomechanical and biodegradability properties, endothelial proliferation capacity, and in vivo pro-angiogenic capabilities of the substrate were also evaluated. Histological staining, immunohistochemistry (IHC) staining for collagen IV, and scanning electron microscope demonstrated that the underlying amniotic and chorionic basement membranes remained intact while the epithelial and trophoblastic layers were entirely removed without considerable damage to basement membranes. The biomechanical evaluation showed that the scaffold is suturable. Proliferation assay, real-time polymerase chain reaction for endothelial adhesion molecules, and IHC demonstrated that both side basement membranes could support the growth of endothelial cells without altering endothelial characteristics. The dorsal skinfold chamber animal model indicated that both side basement membranes could promote angiogenesis. This bi-sided substrate with two exposed surfaces for cultivating various cells would have potential applications in the skin, cardiac, vascularized composite allografts, and microvascular tissue engineering.

No abstract

Decellularized placental membrane has widely been used as scaffold and graft in tissue engineering and regenerative medicine. Exceptional pro-angiogenic and biomechanical properties and low immunogenicity have made the amniochorionic membrane a unique scaffold which provides enriched niche for cellular growth. Herein, an optimized combination of enzymatic solutions (based on Streptokinase) with mechanical scrapping is used to remove the amniotic epithelium and chorion trophoblastic layer, which results in exposing the basement membranes of both sides without their separation and subsequent damages to the in-between spongy layer. Biomechanical and biodegradability properties, endothelial proliferation capacity, and in-vivo pro-angiogenic capabilities of the scaffold were also evaluated. Histological staining and scanning electron microscope (SEM) demonstrated that the underlying amniotic and chorionic basement membranes remained intact while the epithelial and trophoblastic layers were entirely removed without considerable damage to basement membranes. The biomechanical evaluation showed that the scaffold is suturable. Proliferation assay and immunohistochemistry demonstrated that both side basement membranes could support growth of endothelial cells without altering endothelial characteristics. The dorsal skinfold chamber animal model indicated that both side basement membranes could promote angiogenesis. This bi-sided decellularized scaffold with two exposed surfaces for cultivating various cells would have potential applications in skin, cardiac, vascularized composite allografts, and microvascular tissue engineering.

Background: Neonatal seizure is a rare neurologic condition. The current study aimed at determining the etiology of neonatal seizure. Methods: The current study evaluated the data of 100 neonates who were hospitalized at neonatal intensive care unit (NICU) during 2015-2017. A pediatric neurologist made the final diagnosis of seizure. Patients’ medical records were used to review neonatal seizure variables. SPSS (version 16) was used to perform the statistical analyses. Results: The current study enrolled 100 newborns (41% female) admitted to the NICU following the first episode of seizure and the body temperature of 36.8-39.2°C (mean: 37.2°C). Of 100 participants, 94 (94%) had acute symptomatic seizure and 6 (6%) were compatible with neonatal epilepsy syndrome criteria. According to the results, the commonest etiologies were the neonatal encephalopathy and hypoxic-ischemic encephalopathy constituting 82% of participants. Conclusion: The consequences of acute symptomatic seizures in neonates are determined mainly by the etiology of the seizures. Seizure burden and use of anti-seizure drugs may also have some impact, but this has yet to be fully defined.

Background: The purpose of the current study is to estimate the incidence of epilepsy after neonatal seizure (NS) by reviewing of the latest studies on the relationship between NSs and epilepsy in newborns and also discuss risk factors may contribute to this relationship. Methods: A literature review was performed using the search terms "neonatal seizure AND epilepsy," "newborns AND epilepsy," "postneonatal epilepsy." After exclusion of several studies, which did not meet inclusion criteria, the epilepsy incidence rate was measured by dividing the number of all cases of epilepsy who had a history of NS in selected studies considered with the number of all newborns enrolled to the studies minus the number of cases who lost the follow-ups. Results: By reviewing the literature, 13 studies were found, which completely meet the inclusion criteria and published between 2009 and 2019, of which three were population-based while the remaining studies performed hospital-based. Overall, the population evaluated in these series has been estimated to be 2438 newborns of which 454 died, and 300 missed the follow-ups. The incidence rate for afterward epilepsy in all 1684 subjects with NS was 20%, literally 343 of the NS subjects. Conclusion: The presented review enrolled the most recent studies encompassing enough and extended the time as well as adequate sample size. Epilepsy is considered a common outcome of NS, particularly in those with other neurodevelopmental comorbidities, even if there were always several limits associated with various study designs and condition.

There is no robust consensus on whether the more oblique femoral tunnel position offers better results than standard surgical technique in term of operative outcomes. Thus, it is important to determine the thorough position of the femoral tunnels. This study investigated whether a change in the femoral tunnel position in both axial and coronal planes can significantly alter the postoperative functional and clinical outcomes of the patients. Method: This comparative, retrospective, single-center study was performed on 44 patients who had underwent singlebundle Anterior Cruciate Ligament Reconstruction (ACLR). To evaluate the tunnel position in coronal and axial planes, radiographic assessments were done. Based on radiographic data, the patients were classified into 4 groups. The time interval between surgery and last visit averaged 23.6 ± 2.2 months (18-30 mos.). Lysholm knee score, and Cincinnati score were completed for all of the patients. Furthermore, the Lachman, anterior drawer and pivot-shift tests were performed. Results: Of the 44 patients included in the study, 9 patients (20.4%) were classified as the low-anterior group, 17(38.6%) were classified as the lowposterior group and 18(40.9%) were classified as the high-posterior group. None of the patients were included in high-anterior group. A greater mean Lysholm score (96±3) in low-posterior group was the only significant difference between the three groups. Conclusion: Findings of the current study show that with the low-posterior placement of the femoral tunnel, based on both anteroposterior (AP) and tunnel-view x-rays, the better clinical outcomes can be achieved in short-term than the routine tunnel placements

No abstract