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Background: The aim of this network meta-analysis (NMA) was to compare the clinical results obtained after primary reconstruction of orbital floor fractures (OFF) using different materials., Methods: PubMed, Cochrane, and Google Scholar databases were screened from 1989 to 2019. For a study to be eligible, it had to evaluate two or more materials and report the following clinical parameters: diplopia and/or enophthalmos and/or other complications., Results: Nine studies involving 946 patients presenting with an OFF were included. After the surgical procedure, 105 patients (11%) had diplopia, while 43 patients (4.5%) suffered from enophthalmos. The NMA revealed that less postoperative diplopia and enophthalmos were obtained either by using polydioxanone (PDS), or a polymer of l-lactic acid and dl-lactic acid (P[L/DL]LA), or porous polyethylene, or titanium mesh compared with the use of autologous bone grafts., Conclusion: P(L/DL)LA and PDS seem to be the best options for small and intermediate defects, whereas the association of porous polyethylene and titanium should be preferred for larger defects., (© 2020 Wiley Periodicals LLC.)

Objective: The aim of this study is to present and discuss the results of a European multicentre prospective study about pediatric maxillofacial trauma epidemiology during a year., Study Design: The following data were recorded: gender, age, etiology, site of fracture, date of injury. Of the 3396 patients with maxillofacial fractures admitted within the study period, 114 (3.3%) were children aged 15 years and younger, with a male/female ratio of 2.6:1. Mean age was 10.9 years. Most patients (63%) were aged 11-15 years., Results: The most frequent cause of injury was fall (36 patients). Sport injuries and assaults were almost limited to the oldest group, whereas falls were more uniformly distributed in the 3 groups. The most frequently observed fracture involved the mandible with 47 fractures. In particular, 18 condylar fractures were recorded, followed by 12 body fractures., Conclusions: Falls can be acknowledged as the most important cause of facial trauma during the first years of life. The high incidence of sport accidents after 10 years may be a reason to increase the use of mouthguards and other protective equipment. Finally, the mandible (and in particular the condyle) was confirmed as the most frequent fracture site., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Introduction: Oral impalement injuries are common in children. We report a case of severe pharyngeal toothbrush perforation in a 15-month-old infant., Observation: A 15-month-old child was admitted for a penetrating oral injury caused by a toothbrush. There was no hemorrhagic or neurological complication. A CT scan showed the toothbrush in the right parapharyngeal region with its extremity in the mastoid region. Exploration and extraction of the toothbrush was performed under general anesthesia. The outcome was uneventful., Discussion: Penetrating oral cavity wounds caused by a toothbrush in children may be severe and must be explored in the operating room. A preoperative CT scan must be performed to complete the assessment of lesions. The risk of infection is high and an antibiotic prophylaxis is recommended. Neurological and vascular complications may occur but they are rare., (Copyright © 2014 Elsevier Masson SAS. All rights reserved.)

Kindlin-3 (FERMT-3) is known to be central in hemostasis and thrombosis control and its deficiency disrupts platelet aggregation and causes Leukocyte Adhesion Deficiency disease. Here we report that Kindlin-3 has a tumor suppressive role in solid cancer. Our present genetic and functional data show that Kindlin-3 is downregulated in several solid tumors by a mechanism involving gene hypermethylation and deletions. In vivo experiments demonstrated that Kindlin-3 knockdown in 2 tumor cell models (breast cancer and melanoma) markedly increases metastasis formation, in accord with the in vitro increase of tumor cell malignant properties. The metastatic phenotype was supported by a mechanism involving alteration in β3-integrin activation including decreased phosphorylation, interaction with talin and the internalization of its active form leading to less cell attachment and more migration/invasion. These data uncover a novel and unexpected tumor suppressor role of Kindlin-3 which can influence integrins targeted therapies development.

Fragments of five rrp genes encoding response regulators (RRs) in Lactobacillus sakei were amplified by PCR using degenerate oligonucleotide primers. The five rrp genes were part of distinct loci that also comprised hpk genes encoding histidine protein kinases (HPKs). The putative RRs belonged to the OmpR-PhoB subclass of response regulators that consist of N-terminal receiver and C-terminal DNA-binding domains. The putative HPKs were members of the EnvZ-NarX family of orthodox histidine protein kinases which possess two transmembrane segments in a non-conserved N-terminal domain and a C-terminal cytoplasmic kinase domain. Insertional inactivation of the rrp genes indicated that the RRs are implicated in susceptibility to the glycopeptide antibiotic vancomycin, and to extreme pH, temperature and oxidative conditions.

This review summarizes the main structural and biochemical features of the fibrillar constituents of the subendothelial layers of the arterial wall. Several constituents are directly identified by various histochemical methods and electron-microscopic studies. (1) The microfibrils (MF), stained by tannic acid, cationic stains such as ruthenium red, and various peroxidase-labeled lectins are mostly found in association with elastin within the internal elastic lamina (IEL). They have been characterized by chemical analysis as acidic glycoproteins, hydrolyzed by a variety of proteases, but resistant to collagenases. The endothelial cells seem to participate in their biosynthesis. (2) Elastin (El), which is the main constituent of the IEL, forms a wide, concentric, electron-lucent, tannic-acid-stainable zone. Fibrous El results from the association of tropoelastin (or proelastin) molecules by intermolecular cross-linkage. During the elastigenesis, this cross-linkage occurs directly between tropoelastin molecules which have been previously sterically oriented by the MF probably synthetized by the same cells (smooth muscle cells and possibly endothelial cells). (3) Interstitial collagen forms sparse fibers characterized by their cross-striation (with a periodicity of 640 A). They are relatively resistant to most proteolytic enzymes, except collagenases. They result from the intermolecular cross-linkage of rigid molecules, resulting themselves from the intramolecular cross-linkage of three helical alpha chains as a triple helix. The interstitial subendothelial collagen has been identified by indirect immunofluorescence as a type III collagen. The same technique has also been used to detect type IV collagen and fibronectin. This glycoprotein could play a role in the attachment of the endothelial cells to the fibrillar network of the subendothelium, despite an affinity which is greater toward denatured collagen than toward native collagen. One of the most important functions of the subendothelium is its role in thrombogenesis, in which both MF and collagen are involved. In type III collagen, this property is linked to the preservation of an ordered structure in which a 9-amino acids fragment, localized in the central part of each chain, could bear an adhesion site.

In view of its anatomical position, physical characteristics and metabolism, the endothelial cell plays a major part in maintaining the integrity of the vascular system and in the relation between the blood content, both plasma and blood cells, and the wall structure. Where this continuous single layer undergoes anatomical or functional changes, a new equilibrium is set up, an equilibrium which is multifactorial and dynamic. It is governed by the vascular and blood components and by their interrelation; it varies as a function of time and of the biorheological conditions. The interrelationship between the blood content and the wall plays an important part in vascular pathology, especially of the degenerative and thrombotic type. A better understanding of these factors will enhance the possibility of preventing atherogenesis and lay the basis for a coherent and effective therapeutic attitude thrombosis.

Thrombogenicity of the vessel wall: role of the microfibrils and collagen. The study of platelet adhesion to rabbit aortic subendothelium preincubated with highly specific collagenase has revealed that platelets adhere to the microfibrils of the elastic lamina. To certify that an interaction between microfibrils and platelets can occur, microfibrils from two different origins were isolated: placental microfibrils extracted from the villi of human placenta, and aortic microfibrils extracted from adult bovine aorta. Both preparations were histologically homogeneous, and differed in their amino acid composition with an acidic character more pronounced for placental than for aortic microfibrils. Both preparations were able to induce platelet aggregation in plasma, but not after platelet isolation and resuspension in buffer. An interesting feature was the fact that when normal platelets were isolated, washed and resuspended in plasma from severe VWD patients, they were not aggregated by placental or aortic microfibrils. This defect was corrected after perfusion of cryoprecipitate to one patient. Moreover, monoclonal antibody directed against platelet glycoprotein Ib inhibited the aggregation of platelets to microfibrils, not to collagen; this suggested that an axis platelet GPI-FVIII/VWF-microfibrils could represent a pathway for platelet/subendothelium interaction. The adhesion of platelets to collagen seems to involve the staggering of a short amino acid sequence along a collagen fibre. This possibility arises from the requirement for the preservation of the quaternary structure of collagen in the induction of platelet adhesion/aggregation in vitro, and also from the identification and synthesis of a nonapeptide derived from type III collagen, which is also to specifically inhibit the aggregation of platelets by collagen, following its binding to platelet membrane.

The culture medium of bovine aortic endothelial cells contains proteins which inhibit the aggregation of platelets induced by aortic microfibrils but not by type III collagen. From this medium, fibronectin, thrombospondin and a glycoprotein with MW of 128 Kd (GP 128), similar to a glycoprotein described in a microfibrillar extract from bovine aorta were separated by affinity and ion exchange chromatography. GP 128 was further purified by molecular sieve chromatography on SW 3000 column. GP 128 inhibited the aggregation of platelets by microfibrils. This suggests a role of GP 128 in the platelet/subendothelium interaction.

This review deals with some structural features of the collagen molecules involved in the adhesion of platelets representing the initial step of hemostasis, thrombosis, and (partly) atherosclerosis. The adhesion occurs at the level of a vascular lesion or deendothelialized area, whatever the genetic type of collagen. In vitro experiments with purified collagens have shown that vascular interstitial collagens (types I and III, the latter present in subendothelium) as well as basement membrane-derived collagens (types IV and V) induce an adhesion of platelets, provided that an ordered arrangement linked to the quaternary and tertiary structures of their molecule is preserved. Whatever the quaternary structure, the important point seems to be the size of the fibers and more precisely the availability of an optimal number of adhesion sites on multimerized fibers. Various direct or indirect proofs (for example, the occurrence of the impairment of collagen multimerization on platelet adhesion/aggregation) are reviewed. Our recent studies on interstitial collagens have shown the involvement of certain specific amino-acid sequences obtained after cyanogen bromide cleavage of collagen. These are the C-terminal alpha1 (I) CB6 peptide of the alpha 1 chains of type I collagen (216 amino acids) and the central alpha1 (III) CB4 peptide from type III collagen (149 amino acids) Cleavage of this last peptide by chymotrypsin, hydroxylamine, and trypsin has suggested the possibility that a nonapeptide (sequence gly-lys-hyp-gly-glu-hyp-gly-pro-lys) is a minimum site of adhesion for platelets. This assumption has been reinforced by the fact that a synthetic nonapeptide with this sequence specifically inhibits the aggregation of platelets to collagen in vitro. The adhesion of platelets may consequently be due to the repetitive staggering of short amino acid sequences (such as this nonapeptide from type III collagen) along the rigid structure formed by a multimerized collagen fiber.

Two different subendothelial macromolecules have been identified as being thrombogenic: collagen and the microfibrils associated with elastin. The interaction between platelets and collagen involves the binding of platelet membrane receptors by numerous sites repeatedly staggered along a collagen fiber: this explains why the preservation of ordered structures (quaternary and tertiary structures) is so important in the reactivity of collagen towards platelets. In the case of Type III collagen, a nonapeptide has been identified as possibly being part of these repetitive sites. The microfibrils have not yet been characterized, although the biochemical data presently available show that they are acidic glycoproteins resistant to collagenase. Microfibrils extracted from human placenta or bovine aorta induce the aggregation of platelets in a reaction which involves platelet glycoprotein Ib and FVIII/vWF. A general model proposed for explaining platelet adhesion to subendothelium suggests that two different mechanisms should be envisaged depending on the thrombogenic macromolecules (collagen, microfibrils) involved.

A quantitative method (Sepharose test) was devised to measure the adhesion of blood platelets to fibrillar collagen. [14C]5HT-labeled platelets were isolated from plasma, resuspended in EDTA buffer, and incubated with buffer (control) or with fibrillar collagen for 150 sec at 33 degrees C. The mixtures were then filtered through Sepharose 2B columns. In controls the platelets were rapidly eluted, and this was confirmed after 51Cr labeling. [C]5HT was recovered in two stages: 60% with the platelets and 40% retarded, as free 5HT. After incubation with fibrillar collagen (50 micrograms), platelets were retained with the fibrils on the top of the column, and only free [14C]5HT (released from the platelets) was eluted. The percentage of adhesion depended on the number of platelets, the amount of collagen, its degree of polymerization, and the time of incubation at 33 degrees C. [14C]5HT release was markedly diminished when both incubation and filtration were performed at low temperature. ASA, used either in vitro or in vivo in rabbits, did not change the percentage of adhesion but significantly diminished the total amount of [14C]5HT eluted. This method offers a quantitative and reproducible system for the differentiation of adhesion and release, independent of platelet aggregation.