The overall success of a periapical surgery is assessed in terms of regeneration of functional periradicular tissues. The regenerative potential of platelets has been well documented. This article ...describes the use of concentrated growth factors (CGF), a new family of autologous platelet concentrates, as a sole material for bone regeneration after periapical surgery. 32- and 35-year-old female patients diagnosed with Ellis Class IV, an open apex in 11 with apical periodontitis in 11 and 12 and previously root canal-treated 31 and 41 with a chronic apical abscess, respectively, were managed with endodontic surgery. Subsequent to apicectomy and retrograde filling, the CGF fibrin block and membrane were used before suturing. There was uneventful healing during the immediate post-op and the subsequent follow-up periods. CGF is produced by a differential centrifugation process that results in the formation of a denser fibrin matrix richer in growth factors than those observed in PRF. Reasonable osseous healing was seen as early as 6-month follow-up, thereby recommending the use of CGF as an alternative to bone grafts and membranes in extensive periapical lesions to enhance bone regeneration and to decrease the healing time.
Tat/Rev Induced Limiting Dilution Assay (TILDA) is instrumental in estimating the size of latent reservoirs of HIV-1. Here, we report an optimized TILDA containing a broader detection range compared ...to the reported methods and high sensitivity. Giving priority to sequence conservation, we positioned the two forward primers and the probe in exon-1 of HIV-1. The reverse primers are positioned in highly conserved regions of exon-7. The optimized TILDA detected eight molecular clones belonging to five major genetic subtypes of HIV-1 with a comparable detection sensitivity. Using the optimized assay, we show that only a minor proportion of CD4
T cells of primary clinical samples can spontaneously generate multiply spliced viral transcripts. A significantly larger proportion of the cells produced viral transcripts following activation. The optimized TILDA is suitable to characterize HIV-1 latent reservoirs and the therapeutic strategies intended to target the reservoir size.
Bone substitutes have been used by doctors for a long time to treat osseous abnormalities. Recently, scientists have been searching for suitable materials to replace bone. Autogenous bone grafts are ...considered the gold standard for osseous regeneration. However, the limited availability of intraoral sources for grafting material often requires the use of secondary donor sites.
This study aims to compare a control group of standard critical bone defect models treated without any bone transplants to critical size calvarial bony defects treated with various bone replacements, including simvastatin and α-tricalcium phosphate, while analyzing the healing patterns.
In this investigation, 24 Wistar Albino rats weighing 200–250 g were utilized. The study included four groups, each consisting of six rats. Group I utilized deproteinized bovine xenograft, Group II used Simvastatin (0.1 mg), Group III used Simvastatin (0.1 mg) plus TCP, and Group IV served as the untreated calvarial defects group. After eight weeks of testing, the rats were euthanized, and the calvaria were extracted, decalcified in 20% formic acid, and prepared for histological analysis.
The newly produced osseous tissue consisted of woven and lamellar bone, which was observed in all deformities. The mean widths of new bone development in the SIMV with α-TCP (Group III) group after XENO (Group I) and the control group with no graft implantation were 160.33 ± 16.2 µm, 110.59 ± 11.5 µm, and 50.83 ± 5.5 µm, respectively. However, these differences did not show statistical significance (p > 0.05).
The quantity and quality of newly produced osseous tissue were comparable in α-TCP with SIMV and XENO. However, inflammatory infiltration was 8more pronounced in regions where SIMV was present alone compared to the combination group.
The administration of antiretroviral therapy (ART) leads to a rapid reduction in plasma viral load in HIV-1 seropositive subjects. However, when ART is suspended, the virus rebounds due to the ...presence of a latent viral reservoir. Several techniques have been developed to characterize this latent viral reservoir. Of the various assay formats available presently, the Tat/Rev induced limiting dilution assay (TILDA) offers the most robust and technically simple assay strategy. The TILDA formats reported thus far are limited by being selective to one or a few HIV-1 genetic subtypes, thus, restricting them from a broader level application. The novel TILDA, labelled as U-TILDA ('U' for universal), can detect all the major genetic subtypes of HIV-1 unbiasedly, and with comparable sensitivity of detection. U-TILDA is well suited to characterize the latent reservoirs of HIV-1 and aid in the formulation of cure strategies.
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Introduction: The interaction between chlorhexidine (CHX) and sodium hypochlorite (NaOCl) yields a thick precipitate capable of occluding dentinal tubules. Previous studies are unclear as to the ...above-mentioned precipitate contains para-chloroaniline (PCA) or not. PCA is a known toxic and carcinogenic compound which may lead to methemoglobinemia in humans.
Aim: This study aims to evaluate the precipitate formed on combination of different irrigants, weigh the amount of precipitate formed and to analyze the precipitate for PCA by using thin layer chromatography (TLC), high performance liquid chromatography (HPLC), column chromatography (CC), electron spray ionization mass spectrometry (ESI-MS), Ultraviolet (UV), and nuclear magnetic resonance (1H-NMR and C-13 NMR).
Materials and Methods: Four different irrigants namely 2% CHX gluconate, 3% NaOCl, 5% neem and 5% tulsi were taken in different test tubes. Group 1, 2 and 3 included 1 ml 2% CHX combined with 1 ml each of 3% NaOCl, 5% neem and 5% tulsi. Group 4 and 5 comprised of 1 ml 3% NaOCl in combination with 1 ml 5% each of neem and tulsi. Finally, group 6 constituted 1 ml 5% neem mixed with 1 ml 5% tulsi. Each group was observed for 2 min for the formation of any precipitate, and the formed precipitate was weighed and analyzed using 1H-NMR and C-13 NMR, TLC, CC, HPLC, ESI-MS, and UV.
Statistical Analysis: One-way ANOVA and Post hoc-Tukey test were used.
Results: Presence of PCA was detected in group 1 (CHX + NaOCl), group 2 (CHX + neem) and group 3 (CHX + tusli) in all the sensitive methods employed.
Conclusion: The presence of PCA in precipitate was confirmed by TLC, CC, HPLC, ESI-MS, and UV. Based on the results of the present study, we assume that components in CHX are responsible for precipitate formation which contains PCA as well. Extrusion of precipitate beyond the apex may cause periapical tissue damage and delay wound healing at the same time.
Efficient expression of functional proteins in heterologous hosts has become the pivotal focus of modern biotechnology and biomedical research. To this end, multiple alternatives to E. coli are being ...explored for recombinant protein expression. L. lactis, being a gram-positive organism, circumvents the need for an endotoxin removal step during protein purification. We report here the optimisation of the expression of HIV-1 Tat, a notoriously difficult protein, in Lactococcus lactis system. We evaluated five different promoters in two different Lactococcus lactis strains and examined the effect of pH, glucose, and induction time on the yield and purity of Tat. Finally, the recombinant Tat was functionally competent in transactivating the HIV-1 promoter in HLM-1 reporter cells. Our work provides a scaffold for future work on the expression of toxic proteins in Lactococcus lactis.
•Lactococcus lactis is a useful alternative to E. coli for expressing toxic proteins such as HIV-1 Tat.•P2 promoter is the best choice among PepN, NisA, P11, P170 and P2 promoters for HIV-1 Tat expression.•Expression through the P2 promoter demonstrates the least proteolytic processing in the MG1363 strain of L. lactis.•0.25% Glucose without pH adjustment serves as the best nutritional condition for HIV-1 Tat expression.
T‐cell co‐stimulation through CD28/CTLA4:B7‐1/B7‐2 axis is one of the extensively studied pathways that resulted in the discovery of several FDA‐approved drugs for autoimmunity and cancer. However, ...many aspects of the signaling mechanism remain elusive, including oligomeric association and clustering of B7‐2 on the cell surface. Here, we describe the structure of the IgV domain of B7‐2 and its cryptic association into 1D arrays that appear to represent the pre‐signaling state of B7‐2 on the cell membrane. Super‐resolution microscopy experiments on heterologous cells expressing B7‐2 and B7‐1 suggest, B7‐2 form relatively elongated and larger clusters compared to B7‐1. The sequence and structural comparison of other B7 family members, B7‐1:CTLA4 and B7‐2:CTLA‐4 complex structures, support our view that the observed B7‐2 1D zipper array is physiologically important. This observed 1D zipper‐like array also provides an explanation for its clustering, and upright orientation on the cell surface, and avoidance of spurious signaling.
PDB Code(s): 5YXK;
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