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Objectives: The objectives of the study were to determine the association of gingival biotype and secondary stability of orthodontic mini-implants using resonance frequency analysis. Materials and Methods: Twenty patients, each receiving two mini-implants, were divided into two groups; thick and thin gingival biotype based on the thickness of gingiva before mini-implant placement. Implant stability was assessed at the time of placement; at the 1st, 2nd, 3rd, and 4th month by resonance frequency analysis. Peri-implant soft-tissue conditions were also examined at each month till 4 months interval using periodontal indices. Results: Thick and thin gingival biotype groups showed statistically different implant stability quotient (ISQ). Mini-implants showing signs of failure consistently displayed lesser ISQ. Statistically significant difference was observed in the scores of peri-implant indices of failure and no failure group of mini-implants. Conclusion: Mini-implants in thin gingival biotype are more susceptible to failure and peri-implantitis compared to thick gingival biotype. Longitudinal assessment of mini-implant stability may help predict failure so as to avoid long duration and cost of orthodontic treatment.

Graphene-based photodetectors have attracted attention for realizing optoelectronic devices including photodetectors. We report a graphene field effect transistor on silicon for broadband light detection from the ultraviolet to near-infrared region, which is compatible with the silicon technology and does not need a complicated fabrication process. The photodetectors show an improved responsivity. Specifically, fabricated graphene photodetectors shows a photo-responsivity of ~980 A/W at room temperature. These results provide a promising for the development of graphene-based optoelectronic applications with the broadband photodetection from the ultraviolet to near-infrared region.

We are currently witnessing a major epidemic caused by the 2019 novel coronavirus (2019-nCoV). The evolution of 2019-nCoV remains elusive. We found 4 insertions in the spike glycoprotein (S) which are unique to the 2019-nCoV and are not present in other coronaviruses. Importantly, amino acid residues in all the 4 inserts have identity or similarity to those in the HIV-1 gp120 or HIV-1 Gag. Interestingly, despite the inserts being discontinuous on the primary amino acid sequence, 3D-modelling of the 2019-nCoV suggests that they converge to constitute the receptor binding site. The finding of 4 unique inserts in the 2019-nCoV, all of which have identity /similarity to amino acid residues in key structural proteins of HIV-1 is unlikely to be fortuitous in nature. This work provides yet unknown insights on 2019-nCoV and sheds light on the evolution and pathogenicity of this virus with important implications for diagnosis of this virus.

Cellular prion protein (PrP) misfolds into an aberrant and infectious scrapie form (PrPSc) that lead to fatal transmissible spongiform encephalopathies (TSEs). Association of prions with G-quadruplex (GQ) forming nucleic acid motifs has been reported, but implications of these interactions remain elusive. Herein, we show that the promoter region of the human prion gene (PRNP) contains two putative GQ motifs (Q1 and Q2) that assume stable, hybrid, intra-molecular quadruplex structures and bind with high affinity to PrP. Here, we investigate the ability of PrP to bind to the quadruplexes in its own promoter. We used a battery of techniques including SPR, NMR, CD, MD simulations and cell culture-based reporter assays. Our results show that PrP auto-regulates its expression by binding and resolving the GQs present in its own promoter. Furthermore, we map this resolvase-like activity to the N-terminal region (residues 23-89) of PrP. Our findings highlight a positive transcriptional-translational feedback regulation of the PRNP gene by PrP through dynamic unwinding of GQs in its promoter. Taken together, our results shed light on a yet unknown mechanism of regulation of the PRNP gene. This work provides the necessary framework for a plethora of studies on understanding the regulation of PrP levels and its implications in prion pathogenesis.

Background Postoperative suction drains are used after total knee arthroplasty to avoid intra-articular hematoma formation although they can increase blood loss due to a negative suction effect. The use of tranexamic acid to reduce blood loss may nullify this. The aim of this study was to compare outcomes in patients undergoing total knee arthroplasty with or without drains and to analyze whether the drain's diameter also has an impact. Methods This is a prospective randomized study of patients undergoing unilateral total knee arthroplasty performed by a single surgeon. The study population was divided into three groups (A, 10G drain; B, 12G drain; and C, no drain). Pain, blood loss, swelling, wound-related complications, functional outcomes and questionnaire-based outcomes were assessed postoperatively. Results Each group had 35 patients comparable in most demographic and pre- and intraoperative characteristics. During the first 6 hours postoperatively, opioid consumption was significantly higher when the drain was not used (p = 0.036). At 3 months postoperatively, new Knee Society Score (NKSS) was highest with the use of 12G drain (p = 0.018). However, NKSS at 1 year was comparable across the three groups. With the use of tranexamic acid, blood loss and incidence of soakage of dressing were unaffected by the presence or absence of a drain. The calf girth, suprapatellar girth, soakage of dressing and range of motion were comparable in all three groups. There was no incidence of surgical site infection or deep vein thrombosis. Conclusions Presence of a suction drain significantly reduces opioid consumption during the first 6 hours after total knee arthroplasty. Use of a drain made no difference to the functional outcome at 1 year postoperatively. With the use of tranexamic acid in total knee arthroplasty, the total blood loss and the requirement of blood transfusion were unaffected by the presence or absence of closed suction drainage or by the bore of the drain used. The clinical parameters such as swelling, range of motion, infection and deep vein thrombosis also remained the same.

Ulnar nerve compression at guyon’s canal is rare and very few cases have been reported in literature. It can be missed due to its rarity. Symptoms vary from pain and paresthesia to wasting and significant loss of muscle strength, with significant deformities of the hand. The diagnosis is made by detailed history and examination, electromyography, nerve conduction velocity test, ultrasound and magnetic resonance imaging. Early decompression of nerve is treatment of choice. Here we are presenting a case of compression of ulnar nerve in guyon’s canal due to ganglionic cyst.