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Journal of Cellular and Molecular... Feb 2022Fracture non-union represents a common complication, seen in 5%-10% of all acute fractures. Despite the enhancement in scientific understanding and treatment methods,... (Review)
Review
Fracture non-union represents a common complication, seen in 5%-10% of all acute fractures. Despite the enhancement in scientific understanding and treatment methods, rates of fracture non-union remain largely unchanged over the years. This systematic review investigates the biological, molecular and genetic profiles of both (i) non-union tissue and (ii) non-union-related tissues, and the genetic predisposition to fracture non-union. This is crucially important as it could facilitate earlier identification and targeted treatment of high-risk patients, along with improving our understanding on pathophysiology of fracture non-union. Since this is an update on our previous systematic review, we searched the literature indexed in PubMed Medline; Ovid Medline; Embase; Scopus; Google Scholar; and the Cochrane Library using Medical Subject Heading (MeSH) or Title/Abstract words (non-union(s), non-union(s), human, tissue, bone morphogenic protein(s) (BMPs) and MSCs) from August 2014 (date of our previous publication) to 2 October 2021 for non-union tissue studies, whereas no date restrictions imposed on non-union-related tissue studies. Inclusion criteria of this systematic review are human studies investigating the characteristics and properties of non-union tissue and non-union-related tissues, available in full-text English language. Limitations of this systematic review are exclusion of animal studies, the heterogeneity in the definition of non-union and timing of tissue harvest seen in the included studies, and the search term MSC which may result in the exclusion of studies using historical terms such as 'osteoprogenitors' and 'skeletal stem cells'. A total of 24 studies (non-union tissue: n = 10; non-union-related tissues: n = 14) met the inclusion criteria. Soft tissue interposition, bony sclerosis of fracture ends and complete obliteration of medullary canal are commonest macroscopic appearances of non-unions. Non-union tissue colour and surrounding fluid are two important characteristics that could be used clinically to distinguish between septic and aseptic non-unions. Atrophic non-unions had a predominance of endochondral bone formation and lower cellular density, when compared against hypertrophic non-unions. Vascular tissues were present in both atrophic and hypertrophic non-unions, with no difference in vessel density between the two. Studies have found non-union tissue to contain biologically active MSCs with potential for osteoblastic, chondrogenic and adipogenic differentiation. Proliferative capacity of non-union tissue MSCs was comparable to that of bone marrow MSCs. Rates of cell senescence of non-union tissue remain inconclusive and require further investigation. There was a lower BMP expression in non-union site and absent in the extracellular matrix, with no difference observed between atrophic and hypertrophic non-unions. The reduced BMP-7 gene expression and elevated levels of its inhibitors (Chordin, Noggin and Gremlin) could potentially explain impaired bone healing observed in non-union MSCs. Expression of Dkk-1 in osteogenic medium was higher in non-union MSCs. Numerous genetic polymorphisms associated with fracture non-union have been identified, with some involving the BMP and MMP pathways. Further research is required on determining the sensitivity and specificity of molecular and genetic profiling of relevant tissues as a potential screening biomarker for fracture non-unions.
Topics: Animals; Bone Morphogenetic Proteins; Fracture Healing; Fractures, Bone; Fractures, Ununited; Genetic Predisposition to Disease; Humans; Osteogenesis
PubMed: 34984803
DOI: 10.1111/jcmm.17096 -
Frontiers in Cellular Neuroscience 2021Women are more affected by stroke than men. This might, in part, be explained by sex differences in stroke pathophysiology. The hemostasis system is influenced by sex... (Review)
Review
Women are more affected by stroke than men. This might, in part, be explained by sex differences in stroke pathophysiology. The hemostasis system is influenced by sex hormones and associated with female risk factors for stroke, such as migraine. To systematically review possible sex differences in hemostatic related factors in patients with ischemic stroke in general, and the influence of migraine on these factors in women with ischemic stroke. We included 24 studies with data on sex differences of hemostatic factors in 7247 patients with ischemic stroke (mean age 57-72 years, 27-57% women) and 25 hemostatic related factors. Levels of several factors were higher in women compared with men; FVII:C (116% ± 30% vs. 104% ± 30%), FXI (0.14 UI/mL higher in women), PAI-1 (125.35 ± 49.37 vs. 96.67 ± 38.90 ng/mL), D-dimer (1.25 ± 0.31 vs. 0.95 ± 0.24 μg/mL), and aPS (18.7% vs. 12.0% positive). In contrast, protein-S (86.2% ± 23.0% vs. 104.7% ± 19.8% antigen) and P-selectin (48.9 ± 14.4 vs. 79.1 ± 66.7 pg/mL) were higher in men. Most factors were investigated in single studies, at different time points after stroke, and in different stroke subtypes. Only one small study reported data on migraine and hemostatic factors in women with ischemic stroke. No differences in fibrinogen, D-dimer, t-PA, and PAI-1 levels were found between women with and without migraine. Our systematic review suggests that sex differences exist in the activation of the hemostatic system in ischemic stroke. Women seem to lean more toward increased levels of procoagulant factors whereas men exhibit increased levels of coagulation inhibitors. To obtain better insight in sex-related differences in hemostatic factors, additional studies are needed to confirm these findings with special attention for different stroke phases, stroke subtypes, and not in the least women specific risk factors, such as migraine.
PubMed: 34858141
DOI: 10.3389/fncel.2021.711604 -
European Journal of Cancer (Oxford,... Jan 2022Patients with cancer are considered a priority group for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccination given their high risk of contracting... (Meta-Analysis)
Meta-Analysis
Immunogenicity and risk of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection after Coronavirus Disease 2019 (COVID-19) vaccination in patients with cancer: a systematic review and meta-analysis.
BACKGROUND
Patients with cancer are considered a priority group for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) vaccination given their high risk of contracting severe Coronavirus Disease 2019 (COVID-19). However, limited data exist regarding the efficacy of immunisation in this population. In this study, we assess the immunologic response after COVID-19 vaccination of cancer versus non-cancer population.
METHODS
PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science databases were searched from 01st March 2020 through 12th August 12 2021. Primary end-points were anti-SARS-CoV-2 spike protein (S) immunoglobulin G (IgG) seroconversion rates, T-cell response, and documented SARS-CoV-2 infection after COVID-19 immunisation. Data were extracted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Overall effects were pooled using random-effects models.
RESULTS
This systematic review and meta-analysis included 35 original studies. Overall, 51% (95% confidence interval [CI], 41-62) and 73% (95% CI, 64-81) of patients with cancer developed anti-S IgG above the threshold level after partial and complete immunisation, respectively. Patients with haematologic malignancies had a significantly lower seroconversion rate than those with solid tumours after complete immunisation (65% vs 94%; P < 0.0001). Compared with non-cancer controls, oncological patients were less likely to attain seroconversion after incomplete (risk ratio [RR] 0.45 [95% CI 0.35-0.58]) and complete (RR 0.69 [95% CI 0.56-0.84]) COVID-19 immunisation schemes. Patients with cancer had a higher likelihood of having a documented SARS-CoV-2 infection after partial (RR 3.21; 95% CI 0.35-29.04) and complete (RR 2.04; 95% CI 0.38-11.10) immunisation.
CONCLUSIONS
Patients with cancer have an impaired immune response to COVID-19 vaccination compared with controls. Strategies that endorse the completion of vaccination schemes are warranted. Future studies should aim to evaluate different approaches that enhance oncological patients' immune response.
Topics: Antibodies, Viral; COVID-19; COVID-19 Vaccines; Humans; Immunoglobulin G; Neoplasms; SARS-CoV-2; Seroconversion; Spike Glycoprotein, Coronavirus; T-Lymphocytes; Vaccination; COVID-19 Drug Treatment
PubMed: 34794855
DOI: 10.1016/j.ejca.2021.10.014 -
Blood Advances Jan 2022Idiopathic purpura fulminans (IPF) is a rare but severe prothrombotic coagulation disorder that can occur after chickenpox or human herpesvirus 6 (HHV-6) infection. IPF...
Idiopathic purpura fulminans (IPF) is a rare but severe prothrombotic coagulation disorder that can occur after chickenpox or human herpesvirus 6 (HHV-6) infection. IPF leads to an autoantibody-mediated decrease in the plasma concentration of protein S. We conducted a retrospective multicenter study involving patients with IPF from 13 French pediatric centers and a systematic review of cases in published literature. Eighteen patients were included in our case series, and 34 patients were included as literature review cases. The median age was 4.9 years, and the diagnostic delay after the first signs of viral infection was 7 days. The lower limbs were involved in 49 patients (94%) with typical lesions. In all, 41 patients (78%) had a recent history of varicella-zoster virus infection, and 7 patients (14%) had been infected by HHV-6. Most of the patients received heparin (n = 51; 98%) and fresh frozen plasma transfusions (n = 41; 79%); other treatment options were immunoglobulin infusion, platelet transfusion, corticosteroid therapy, plasmapheresis, and coagulation regulator concentrate infusion. The antithrombin level and platelet count at diagnosis seemed to be associated with severe complications. Given the rarity of this disease, the creation of a prospective international registry is required to consolidate these findings.
Topics: Child; Child, Preschool; Humans; Chickenpox; Delayed Diagnosis; Prospective Studies; Protein S; Purpura Fulminans; Retrospective Studies
PubMed: 34788405
DOI: 10.1182/bloodadvances.2021005126 -
Traffic (Copenhagen, Denmark) Dec 2021Endoplasmic reticulum (ER)-to-Golgi trafficking is an essential and highly conserved cellular process. The coat protein complex-II (COPII) arm of the trafficking... (Review)
Review
Endoplasmic reticulum (ER)-to-Golgi trafficking is an essential and highly conserved cellular process. The coat protein complex-II (COPII) arm of the trafficking machinery incorporates a wide array of cargo proteins into vesicles through direct or indirect interactions with Sec24, the principal subunit of the COPII coat. Approximately one-third of all mammalian proteins rely on the COPII-mediated secretory pathway for membrane insertion or secretion. There are four mammalian Sec24 paralogs and three yeast Sec24 paralogs with emerging evidence of paralog-specific cargo interaction motifs. Furthermore, individual paralogs also differ in their affinity for a subset of sorting motifs present on cargo proteins. As with many aspects of protein trafficking, we lack a systematic and thorough understanding of the interaction of Sec24 with cargoes. This systematic review focuses on the current knowledge of cargo binding to both yeast and mammalian Sec24 paralogs and their ER export motifs. The analyses show that Sec24 paralog specificity of cargo (and cargo receptors) range from exclusive paralog dependence or preference to partial redundancy. We also discuss how the Sec24 secretion system is hijacked by viral (eg, VSV-G, Hepatitis B envelope protein) and bacterial (eg, the enteropathogenic Escherichia coli type III secretion system effector NleA/EspI) pathogens.
Topics: Animals; COP-Coated Vesicles; Endoplasmic Reticulum; Golgi Apparatus; Mammals; Membrane Proteins; Protein Transport; Proteins; Saccharomyces cerevisiae; Saccharomyces cerevisiae Proteins; Secretory Pathway
PubMed: 34533884
DOI: 10.1111/tra.12817 -
BioMed Research International 2021The SARS-CoV-2 virus is the cause of the latest pandemic of the 21st century; it is responsible for the development of COVID-19. Within the multiple study models for...
BACKGROUND
The SARS-CoV-2 virus is the cause of the latest pandemic of the 21st century; it is responsible for the development of COVID-19. Within the multiple study models for both the biology and the treatment of SARS-CoV-2, the use of stem cells has been proposed because of their ability to increase the immune response and to repair tissue. Therefore, the objective of this review is to evaluate the role of stem cells against SARS-CoV-2 and COVID-19 in order to identify their potential as a study model and as a possible therapeutic source against tissue damage caused by this virus. Therefore, the following research question was established: What is the role of stem cells in the study of SARS-CoV-2 and the treatment of COVID-19?
MATERIALS AND METHODS
A search was carried out in the electronic databases of PUBMED, Scopus, and ScienceDirect. The following keywords were used: "SARS-CoV-2," "COVID-19," and "STEM CELL," plus independent search strategies with the Boolean operators "OR" and "AND." The identified reports were those whose main objective was the study of stem cells in relation to SARS-CoV-2 or COVID-19. For the development of this study, the following inclusion criteria were taken into account: studies whose main objective was the study of stem cells in relation to SARS-CoV-2 or COVID-19 and clinical case studies, case reports, clinical trials, pilot studies, in vitro, or in vivo studies. For assessment of the risk of bias for in vitro studies, the SciRAP tool was used. The data collected for each type of study, clinical or in vitro, were analyzed with descriptive statistics using the SPSS V.22 program.
RESULTS
Of the total of studies included ( = 39), 22 corresponded to in vitro investigations and 17 to human studies (clinical cases ( = 9), case series ( = 2), pilot clinical trials ( = 5), clinical trials ( = 1)). In vitro studies that induced pluripotent stem cells were the most used ( = 12), and in clinical studies, the umbilical stem cells derived were the most reported ( = 11). The mean age of the study subjects was 58.3 years. After the application of stem cell therapy, the follow-up period was 8 days minimum and 90 days maximum. . The mechanism by which the virus enters the cell is through protein "S," located on the surface of the membrane, by recognizing the ACE2 receptor located on the target cell. The evidence that the expression of ACE2 and TMPRSS2 in stem cells indicates that stem cells from bone marrow and amniotic fluid have very little expression. This shows that stem cell has a low risk of infection with SARS-CoV-2.
CONCLUSION
The use of stem cells is a highly relevant therapeutic option. It has been shown in both in vitro studies and clinical trials that it counteracts the excessive secretion of cytokines. There are even more studies that focus on long-term follow-up; thus, the potential for major side effects can be analyzed more clearly. Finally, the ethical use of stem cells from fetal or infant origin needs to be regulated. The study was registered in PROSPERO (no. CRD42021229038). The limitations of the study were because of the methodology employed, the sample was not very large, and the follow-up period of the clinical studies was relatively short.
Topics: COVID-19; Clinical Trials as Topic; Humans; SARS-CoV-2; Stem Cell Transplantation; Stem Cells
PubMed: 34458372
DOI: 10.1155/2021/9915927 -
Frontiers in Immunology 2021The immune system is unique among all biological sub-systems in its usage of DNA-editing enzymes to introduce targeted gene mutations and double-strand DNA breaks to...
Evolutionary Comparative Analyses of DNA-Editing Enzymes of the Immune System: From 5-Dimensional Description of Protein Structures to Immunological Insights and Applications to Protein Engineering.
The immune system is unique among all biological sub-systems in its usage of DNA-editing enzymes to introduce targeted gene mutations and double-strand DNA breaks to diversify antigen receptor genes and combat viral infections. These processes, initiated by specific DNA-editing enzymes, often result in mistargeted induction of genome lesions that initiate and drive cancers. Like other molecules involved in human health and disease, the DNA-editing enzymes of the immune system have been intensively studied in humans and mice, with little attention paid (< 1% of published studies) to the same enzymes in evolutionarily distant species. Here, we present a systematic review of the literature on the characterization of one such DNA-editing enzyme, activation-induced cytidine deaminase (AID), from an evolutionary comparative perspective. The central thesis of this review is that although the evolutionary comparative approach represents a minuscule fraction of published works on this and other DNA-editing enzymes, this approach has made significant impacts across the fields of structural biology, immunology, and cancer research. Using AID as an example, we highlight the value of the evolutionary comparative approach in discoveries already made, and in the context of emerging directions in immunology and protein engineering. We introduce the concept of 5-dimensional (5D) description of protein structures, a more nuanced view of a structure that is made possible by evolutionary comparative studies. In this higher dimensional view of a protein's structure, the classical 3-dimensional (3D) structure is integrated in the context of real-time conformations and evolutionary time shifts (4 dimension) and the relevance of these dynamics to its biological function (5 dimension).
Topics: Animals; Biological Evolution; Cytidine Deaminase; DNA; Humans; Protein Conformation; Protein Engineering
PubMed: 34135887
DOI: 10.3389/fimmu.2021.642343 -
Human Reproduction (Oxford, England) Apr 2021Is there an association between hereditary thrombophilia in pregnant women and risk of recurrent pregnancy loss (RPL)? (Meta-Analysis)
Meta-Analysis
STUDY QUESTION
Is there an association between hereditary thrombophilia in pregnant women and risk of recurrent pregnancy loss (RPL)?
SUMMARY ANSWER
Pregnant women with hereditary thrombophilia have an increased risk of RPL, especially for pregnant women with the G1691A mutation of the factor V Leiden (FVL) gene, the G20210A mutation of the prothrombin gene (PGM), and deficiency of protein S (PS).
WHAT IS KNOWN ALREADY
Prior studies have suggested that pregnant women with hereditary thrombophilia have a higher risk of RPL, however, the results are inconsistent; furthermore, a complete overview is missing. This lack of information is an obstacle to the risk assessment of RPL in pregnant women with hereditary thrombophilia. A comprehensive meta-analysis on the relation between hereditary thrombophilia and the risk of RPL is needed.
STUDY DESIGN, SIZE, DURATION
A systematic review and meta-analysis was performed using observational studies published in English before 1 April 2020 to evaluate the relation between hereditary thrombophilia and risk of RPL.
PARTICIPANTS/MATERIALS, SETTING, METHODS
Relevant studies were identified from PubMed, Web of Science, and EMBASE searches and complemented with perusal of bibliographies of retrieved articles. The exposure of interest was hereditary thrombophilia, including FVL mutation, PGM, deficiency of antithrombin (AT), deficiency of protein C (PC), and deficiency of PS. The overall risk estimates were pooled using random effects models. Subgroup and sensitivity analyses were carried out to explore possible sources of heterogeneity and assess the robustness of the results.
MAIN RESULTS AND THE ROLE OF CHANCE
A total of 89 studies involving 30 254 individuals were included. Results showed that women with FVL mutation (odds ratio (OR): 2.44, 95% CI: 1.96-3.03), PGM (OR: 2.08, 95% CI: 1.61-2.68), or deficiency of PS (OR: 3.45, 95% CI: 1.15-10.35) had higher risks of developing RPL. Compared with the reference group, there was no observed relation between a deficiency in AT or PC and RPL (all P > 0.05). Heterogeneity in the risk estimates of RPL was partially explained by geographic region, definitions of RPL, types of RPL, and controlled confounders. Sensitivity analyses validated the robustness of the findings.
LIMITATIONS, REASONS FOR CAUTION
Only 39 of the included studies controlled for one or more confounders, and the heterogeneity across all included studies was high. Based on the data available, we cannot determine whether this association is confounded by other potential risk factors of RPL.
WIDER IMPLICATIONS OF THE FINDINGS
This systematic review and meta-analysis show a possible association between hereditary thrombophilia and an increased risk of RPL, suggesting that testing for hereditary thrombophilia should be considered in individuals with RPL.
STUDY FUNDING/COMPETING INTEREST(S)
The study was funded by the Hunan Provincial Key Research and Development Program (Grant number: 2018SK2062) and National Natural Science Foundation Program (Grant number: 81973137). There are no conflicts of interest.
REGISTRATION NUMBER
N/A.
Topics: Abortion, Habitual; Female; Humans; Mutation; Odds Ratio; Pregnancy; Risk Factors; Thrombophilia
PubMed: 33575779
DOI: 10.1093/humrep/deab010 -
Journal of Thrombosis and Haemostasis :... Dec 2020Retinal vascular occlusion is a leading cause of sight loss. Both retinal artery occlusion (RAO) and retinal vein occlusion (RVO) have been associated with... (Meta-Analysis)
Meta-Analysis
BACKGROUND
Retinal vascular occlusion is a leading cause of sight loss. Both retinal artery occlusion (RAO) and retinal vein occlusion (RVO) have been associated with hypercoagulable states; however, the burden of thrombophilia in these patients is unclear.
OBJECTIVES
This study aims at estimating the prevalence of inherited and acquired thrombophilias in adults with RAO or RVO through a systematic review and meta-analysis of the literature.
PATIENTS/METHODS
PubMed and EMBASE were systematically searched from inception to 29 February 2020. All studies reporting prevalences of factor V Leiden (FVL) and prothrombin (F-II) G20210A mutations, methylenetetrahydrofolate reductase (MTHFR) C677T and plasminogen activator inhibitor (PAI) 4G polymorphisms, antithrombin III (AT-III), protein C (PC) and protein S (PS) activity deficiencies, hyperhomocysteinemia, and antiphospholipid (APL) antibodies in adults with RAO or RVO were included. Pooled prevalences and 95% confidence intervals (CI) were calculated.
RESULTS
Ninety-five studies were included; FVL and F-II mutations were found in 6% (95% CI: 5-8) and 3% (95% CI: 2-4) of individuals with RVO, respectively, whereas AT-III, PC, and PS activity deficiencies were found in <2%. The MTHFR C677T and PAI 4G homozygous polymorphism were observed in 13% (95% CI: 10-17) and 23% (95% CI: 16-31) of RVO, respectively; 8% presented APL antibodies. Similar findings were observed in individuals with RAO.
CONCLUSIONS
Compared with healthy subjects, patients with retinal vascular occlusion showed similar prevalences of inherited and acquired thrombophilias. These findings do not support routine thrombophilia screening in individuals with RAO or RVO.
Topics: Adult; Factor V; Humans; Methylenetetrahydrofolate Reductase (NADPH2); Prothrombin; Retinal Vein Occlusion; Risk Factors; Thrombophilia
PubMed: 32805772
DOI: 10.1111/jth.15068 -
Virologica Sinica Feb 2021Tyro3, Axl, and Mertk (TAM) receptors play multiple roles in a myriad of physiological and pathological processes, varying from promoting the phagocytic clearance of...
Tyro3, Axl, and Mertk (TAM) receptors play multiple roles in a myriad of physiological and pathological processes, varying from promoting the phagocytic clearance of apoptotic cells, sustaining the immune and inflammatory homeostasis, maintaining the blood-brain barrier (BBB) integrity and central nervous system (CNS) homeostasis, to mediating cancer malignancy and chemoresistance. Growth arrest-specific protein 6 (Gas6) and protein S (Pros1) are the two ligands that activate TAM receptors. Recently, TAM receptors have been reported to mediate cell entry and infection of multitudinous enveloped viruses in a manner called apoptotic mimicry. Moreover, TAM receptors are revitalized during viral entry and infection, which sequesters innate immune and inflammatory responses, facilitating viral replication and immune evasion. However, accumulating evidence have now proposed that TAM receptors are not required for the infection of these viruses in vivo. In addition, TAM receptors protect mice against the CNS infection of neuroinvasive viruses and relieve the brain lesions during encephalitis. These protective effects are achieved through maintaining BBB integrity, attenuating proinflammatory cytokine production, and promoting neural cell survival. TAM receptors also regulate the programmed cell death modes of virus-infected cells, which have profound impacts on the pathogenesis and outcome of infection. Here, we systematically review the functionalities and underlying mechanisms of TAM receptors and propose the potential application of TAM agonists to prevent severe viral encephalitis.
Topics: Animals; Mice; Proto-Oncogene Proteins; Receptor Protein-Tyrosine Kinases; Signal Transduction; Virus Diseases; c-Mer Tyrosine Kinase
PubMed: 32720213
DOI: 10.1007/s12250-020-00264-9