ABSTRACT
Hemoglobin (Hb) Chile, a variant of Hb M, is produced by a point mutation of CTGâATG on codon 29 (legacy codon 28) of the Hb ß locus gene, which results in an amino acid substitution of LeuâMet. It has been identified in two families worldwide and is inherited in an autosomal dominant manner. Here, we report a case of Hb Chile in which a de novo mutation was detected in the proband. A 17-year-old male presented to the outpatient clinic with a pale appearance. There was cyanosis on his lips and fingers. Blood tests indicated the existence of hemolysis, but complete blood counts revealed no anemia. Peripheral arterial oxygen saturation on pulse oximetry was 80% on room air and did not improve with oxygen supplementation. The level of methemoglobin was 15.4%. Targeted next-generation sequencing identified a heterozygous NM_000518.4(HBB):c.85C > A mutation, indicating Hb Chile. The Hb Chile mutation, on the other hand, was not discovered in his parents, implying that it arose as a result of a de novo mutation. This case highlights the necessity of suspecting Hb gene mutations in patients with unexplained chronic methemoglobinemia, even if there is no family history.
ABSTRACT
OBJECTIVE: This study aimed to investigate the effects of dodecacalcium hepta-aluminate (C12A7) content on some physicochemical properties and cytocompatibility of tricalcium silicate (C3S) cement using human dental pulp cells (hDPCs). MATERIAL AND METHODS: High purity C3S cement was manufactured by a solid phase method. C12A7 was mixed with the cement in proportions of 0, 5, 8, and 10 wt% (C12A7-0, -5, -8, and -10, respectively). Physicochemical properties including initial setting time, compressive strength, and alkalinity were evaluated. Cytocompatibility was assessed with cell viability tests and cell number counts. Statistical analysis was performed by using one-way analysis of variance (ANOVA) and Tukey's test (p<0.05). RESULTS: The initial setting time of C3S-based cement was shorter in the presence of C12A7 (p<0.05). After 1 day, C12A7-5 showed significantly higher compressive strength than the other groups (p<0.05). After 7 days, the compressive strength of C12A7-5 was similar to that of C12A7-0, whereas other groups showed strength lower than C12A7-0. The pH values of all tested groups showed no significant differences after 1 day (p>0.05). The C12A7-5 group showed similar cell viability to the C12A7-0 group (p>0.05), while the other experimental groups showed lower values compared to C12A7-0 group (p<0.05). The number of cells grown on the C12A7-5 specimen was higher than that on C12A7-8 and -10 (p<0.05). CONCLUSIONS: The addition of C12A7 to C3S cement at a proportion of 5% resulted in rapid initial setting time and higher compressive strength with no adverse effects on cytocompatibility.
Subject(s)
Aluminum Compounds/chemistry , Calcium Compounds/chemistry , Dental Cements/chemistry , Dental Pulp Cavity/cytology , Silicates/chemistry , Aluminum Compounds/pharmacology , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology , Calcium Compounds/pharmacology , Cell Survival/drug effects , Cells, Cultured , Compressive Strength , Dental Cements/pharmacology , Dental Pulp Cavity/drug effects , Humans , Materials Testing , Microscopy, Electron, Scanning , Particle Size , Reference Values , Reproducibility of Results , Silicates/pharmacology , Time Factors , X-Ray DiffractionABSTRACT
Abstract Objective This study aimed to investigate the effects of dodecacalcium hepta-aluminate (C12A7) content on some physicochemical properties and cytocompatibility of tricalcium silicate (C3S) cement using human dental pulp cells (hDPCs). Material and Methods High purity C3S cement was manufactured by a solid phase method. C12A7 was mixed with the cement in proportions of 0, 5, 8, and 10 wt% (C12A7-0, −5, −8, and −10, respectively). Physicochemical properties including initial setting time, compressive strength, and alkalinity were evaluated. Cytocompatibility was assessed with cell viability tests and cell number counts. Statistical analysis was performed by using one-way analysis of variance (ANOVA) and Tukey's test (p<0.05). Results The initial setting time of C3S-based cement was shorter in the presence of C12A7 (p<0.05). After 1 day, C12A7-5 showed significantly higher compressive strength than the other groups (p<0.05). After 7 days, the compressive strength of C12A7-5 was similar to that of C12A7-0, whereas other groups showed strength lower than C12A7-0. The pH values of all tested groups showed no significant differences after 1 day (p>0.05). The C12A7-5 group showed similar cell viability to the C12A7-0 group (p>0.05), while the other experimental groups showed lower values compared to C12A7-0 group (p<0.05). The number of cells grown on the C12A7-5 specimen was higher than that on C12A7-8 and −10 (p<0.05). Conclusions The addition of C12A7 to C3S cement at a proportion of 5% resulted in rapid initial setting time and higher compressive strength with no adverse effects on cytocompatibility.
Subject(s)
Humans , Silicates/chemistry , Calcium Compounds/chemistry , Aluminum Compounds/chemistry , Dental Cements/chemistry , Dental Pulp Cavity/cytology , Particle Size , Reference Values , Time Factors , X-Ray Diffraction , Biocompatible Materials/pharmacology , Biocompatible Materials/chemistry , Materials Testing , Microscopy, Electron, Scanning , Cell Survival/drug effects , Cells, Cultured , Reproducibility of Results , Silicates/pharmacology , Calcium Compounds/pharmacology , Aluminum Compounds/pharmacology , Compressive Strength , Dental Cements/pharmacology , Dental Pulp Cavity/drug effectsABSTRACT
Binding of Mycobacterium leprae to and invasion of Schwann cells (SC) represent a crucial step that initiates nerve damage in leprosy. We and others have described that M. leprae colonization of the peripheral nerve system may be mediated in part by a surface-exposed histone-like protein (Hlp), characterized as a laminin-binding protein (LBP). Hlp/LBP has also been shown to play a role in the binding of mycobacteria to alveolar epithelial cells and macrophages. In the present study we report that M. leprae expresses Hlp/LBP protein during the course of human infection. Additionally, we analyzed the interaction of Hlp/LBP with the extracellular matrix and host cell surface. We show that Hlp/LBP, besides laminin, also binds heparin and heparan sulfate. Testing truncated recombinant Hlp molecules corresponding to the N-terminal (rHlp-N) and the C-terminal (rHlp-C) domains of the protein, we established that interaction of Hlp/LBP with laminin-2 and heparin is mainly mediated by the C-terminal domain of the protein. Moreover, the same domain was found to be involved in Hlp/LBP-mediating bacterial binding to human SC. Finally, evidence is shown suggesting that M. leprae produces a post-translationally modified Hlp/LBP containing methyllysine residues. Methylation of the lysine residues, however, seems not to affect the adhesive properties of Hlp/LBP. Taken together, our observations reinforce the involvement of Hlp/LBP as an adhesin in mycobacterial infections and define its highly positive C-terminal region as the major adhesive domain of this protein.