Clinical Success of Two Working Length Determination Techniques: A Randomized Controlled Trial

OBJECTIVE: To determine the clinical success of two working length determination techniques using Electronic apex locator (Root ZX mini) and Radiographic method. MATERIALS AND METHODS: In this study, 83 teeth from 64 patients were randomly divided into groups; Group A: Electronic apex locator and Group B: Radiographic technique. A pre-operative radiograph was taken using customized tube positioners. After standard isolation and access cavity preparation, WL determination was carried out using Electronic apex locator in group A where as in group B pre-operative radiograph was used. After standardized cleaning and shaping technique, master cone verification radiograph was taken as the primary outcome and adjustments were accordingly made. After obturation, post-operative radiograph was taken. Differences in the end point of obturation and calculated working length were taken as the secondary outcome. Patients were recalled after 3 months. Clinical and radiographic evaluation of success was assessed as tertiary outcome. RESULTS: Accuracy of fit of master cone as verified by the radiograph (0.5mm short of radiographic apex) was the primary outcome. The frequency of under extension was not statistically significantly different between the 2 groups. Frequency of over extension and accurate fit was significantly different between the 2 groups. When absolute values of under extension was analysed, there was a statistically significant difference among the 2 groups. However, there was no significant difference between the 2 groups for absolute values of over extension. The accuracy of obturation (0.5mm short of radiographic apex) as verified by the post obturation radiograph was the secondary outcome assessed. It was not significantly different between the 2 groups. The tertiary outcome of success rate of endodontic treatment after 3 months of obturation was assessed by presence or absence by clinical symptoms of disease and radiographic evidence of reduction or increase in peri-apical lesion. There was no significant difference in the clinical outcome of endodontic treatment. There was no significant difference in the lesion reduction between the 2 groups. However, 1 tooth in Group A (Electronic apex locator) developed a lesion. CONCLUSION: The new radiographic technique showed greater frequency of over estimation than Electronic apex locator. It was similar to Electronic apex locator in the under estimation. However, there was no statistical difference in the long term success or the absolute values of over estimation. Hence, the new single radiographic technique for working length determination can be used as an alternative to Electronic apex locators

Proteomic characterisation of endoplasmic reticulum-derived protein bodies in tobacco leaves

<p>Abstract</p> <p>Background</p> <p>The N-terminal proline-rich domain (Zera) of the maize storage protein γ-zein, is able to induce the formation of endoplasmic reticulum (ER)-derived protein bodies (PBs) when fused to proteins of interest. This encapsulation enables a recombinant fused protein to escape from degradation and facilitates its recovery from plant biomass by gradient purification. The aim of the present work was to evaluate if induced PBs encapsulate additional proteins jointly with the recombinant protein. The exhaustive analysis of protein composition of PBs is expected to facilitate a better understanding of PB formation and the optimization of recombinant protein purification approaches from these organelles.</p> <p>Results</p> <p>We analysed the proteome of PBs induced in <it>Nicotiana benthamiana </it>leaves by transient transformation with Zera fused to a fluorescent marker protein (DsRed). Intact PBs with their surrounding ER-membrane were isolated on iodixanol based density gradients and their integrity verified by confocal and electron microscopy. SDS-PAGE analysis of isolated PBs showed that Zera-DsRed accounted for around 85% of PB proteins in term of abundance. Differential extraction of PBs was performed for in-depth analysis of their proteome and structure. Besides Zera-DsRed, 195 additional proteins were identified including a broad range of proteins resident or trafficking through the ER and recruited within the Zera-DsRed polymer.</p> <p>Conclusions</p> <p>This study indicates that Zera-protein fusion is still the major protein component of the new formed organelle in tobacco leaves. The analysis also reveals the presence of an unexpected diversity of proteins in PBs derived from both the insoluble Zera-DsRed polymer formation, including ER-resident and secretory proteins, and a secretory stress response induced most likely by the recombinant protein overloading. Knowledge of PBs protein composition is likely to be useful to optimize downstream purification of recombinant proteins in molecular farming applications.</p

Feasibility of store-and-forward teledermatology in out-patient care: A prospective study from rural India utilising specialist referral services through an instant messaging platform - "WhatsApp"

Objectives: The COVID-19 pandemic has placed unprecedented demands on the delivery of health care in rural areas of India. We examined the feasibility of store-and-forward mobile teledermatology for outpatient access to specialist dermatologic care in underserved areas in India. Methods: We conducted a prospective study using smartphone-based teledermatology, connecting six underserved clinics manned by primary care physicians (PCP) to three dermatologists, using the instant messaging platform WhatsApp. We assessed the concordance between PCPs and dermatologists (using Cohen’s kappa coefficient), consultation time, the spectrum of conditions, and the outcome. Results: Of the 730 dermatology patients screened in the clinics, (13%) (36 males and 59 females) required teleconsultation, among which 61.1% were non-infective, 34.7% were infective, and the diagnosis could not be ascertained in 4.2 %. The mean time takenwas 13.5 (± 18.4) minutes. Twenty per cent (n=19) required referral, and 80% (n=76) of consultations could be resolved at the clinic, of whom 36.8 % were cured, 38.2% had moderate, 4% had minimal improvement, 13% were lost to follow-up, and 8% refused treatment. Cure was observed in viral infections and eczema. The diagnostic concordance ranged from low values [0.38 (95% CI: 0-0.68)] in infective to moderate [0.66 (95% CI: 0.42-0.83), p=0.033] in non-infective disorders. Conclusion: Asynchronous mobile teledermatology, using specialist referral via instant messaging platforms, is a powerful modality for providing real-time dermatologic care, while offering a very promising alternative for decreasing healthcare disparities and continuity of services even in adverse situations like the Covid-19 pandemic

Artificially-induced organelles are optimal targets for optical trapping experiments in living cells

Optical trapping supplies information on the structural, kinetic or rheological properties of inner constituents of the cell. However, the application of significant forces to intracellular objects is notoriously difficult due to a combination of factors, such as the small difference between the refractive indices of the target structures and the cytoplasm. Here we discuss the possibility of artificially inducing the formation of spherical organelles in the endoplasmic reticulum, which would contain densely packed engineered proteins, to be used as optimized targets for optical trapping experiments. The high index of refraction and large size of our organelles provide a firm grip for optical trapping and thereby allow us to exert large forces easily within safe irradiation limits. This has clear advantages over alternative probes, such as subcellular organelles or internalized synthetic beads

ANTIMICROBIAL ACTIVITIES OF NATURAL AND RECOMBINANT SPIDER SILK – A REVIEW

Spider silk is a protein fibre spun by spiders and they use their silk for a variety of purposes such as for making webs or other structures, which function as sticky nets to catch their prey, or as nets or cocoons to protect their offspring, or for depositing sperms etc. It has a variety of properties that make them useful in a range of potential industrial and medical applications. Spider silk has been used for making fishing gears and lures, weaving ceremonial and bullet- proof garments and also used clinically as surgical sutures for centuries due to its biocompatibility, slow degradability and high tensile strength. Research on its antibacterial activity is important for humans as they are facing novel and harmful pathogens day by day. Most of the microorganisms are becoming resistant to many antibacterial agents. This review is an attempt to discuss the antimicrobial activities of natural and recombinant spider silk. Our studies revealed that antibacterial activities are exhibited by the silk of some specific species of spiders. (Pardosa brevivulva, Eriovixia excelsa, Stegodyphus sarasinorum, Cyclosa confraga, Nephila pilipes, Pholcus phalangioides, Tegenaria domestica, Pityohyphantes phrygianus, Parawixia dehaani, Crossopriza lyoni, Neoscona theisi and Argiope trifasciata). The silk of some spider species (Linothele fallax, Linothele megatheloides, Argiope aurantia and Latrodectus hesperus) do not show such activity. It was observed that gram positive bacteria are more susceptible to spider silk than gram negative bacteria. Recombinant spider silk also possesses a high potential for biomedical applications because of its anti-microbial property, biocompatibility and biodegradability. Antimicrobial properties of spider silk can also be influenced by the diet and environmental conditions. Further future studies in this regard may lead to the discovery of novel biomaterials and new therapeutic drugs against microbes which will be of great significance especially in this pandemic situation

Divergent Small Tim Homologues Are Associated with TbTim17 and Critical for the Biogenesis of TbTim17 Protein Complexes in Trypanosoma brucei

Trypanosoma brucei is the causative agent of African sleeping sickness. The parasite’s mitochondrion represents a useful source for potential chemotherapeutic targets. Similarly to yeast and humans, mitochondrial functions depend on the import of proteins that are encoded in the nucleus and made in the cytosol. Even though the machinery involved in this mitochondrial protein import process is becoming clearer in T. brucei, a comprehensive picture of protein complex composition and function is still lacking. In this study, we characterized three T. brucei small Tim proteins, TbTim9, TbTim10, and TbTim8/13. Although the parasite does not have the classical TIM22 complex that imports mitochondrial inner membrane proteins containing internal targeting signals in yeast or humans, we found that these small TbTims associate with TbTim17, the major subunit of the TbTIM complex in T. brucei, and play an essential role in the stability of the TbTim17 complexes. Therefore, these divergent proteins are critical for mitochondrial protein biogenesis in T. brucei.The small Tim proteins belong to a group of mitochondrial intermembrane space chaperones that aid in the import of mitochondrial inner membrane proteins with internal targeting signals. Trypanosoma brucei, the protozoan parasite that causes African trypanosomiasis, possesses multiple small Tim proteins that include homologues of T. brucei Tim9 (TbTim9) and Tim10 (TbTim10) and a unique small Tim that shares homology with both Tim8 and Tim13 (TbTim8/13). Here, we found that these three small TbTims are expressed as soluble mitochondrial intermembrane space proteins. Coimmunoprecipitation and mass spectrometry analysis showed that the small TbTims stably associated with each other and with TbTim17, the major component of the mitochondrial inner membrane translocase in T. brucei. Yeast two-hybrid analysis indicated direct interactions among the small TbTims; however, their interaction patterns appeared to be different from those of their counterparts in yeast and humans. Knockdown of the small TbTims reduced cell growth and decreased the steady-state level of TbTim17 and T. brucei ADP/ATP carrier (TbAAC), two polytopic mitochondrial inner membrane proteins. Knockdown of small TbTims also reduced the matured complexes of TbTim17 in mitochondria. Depletion of any of the small TbTims reduced TbTim17 import moderately but greatly hampered the stability of the TbTim17 complexes in T. brucei. Altogether, our results revealed that TbTim9, TbTim10, and TbTim8/13 interact with each other, associate with TbTim17, and play a crucial role in the integrity and maintenance of the levels of TbTim17 complexes

Growth and characterization of Sm3+ doped cerium oxalate single crystals

Single crystals of Sm3+ doped cerium oxalate decahydrate were synthesized using single diffusion gel technique and the conditions influencing the size, morphology, nucleation density and quality of the crystals were optimized. Highly transparent single crystals of average size 3 mm × 2 mm × 1 mm with well-defined hexagonal morphology were grown during a time period of two weeks. X-ray powder diffraction analysis revealed that the grown crystals crystallize in the monoclinic system with space group P21/c as identical with the pure cerium oxalate. The various functional groups of the oxalate ligand and the water of crystallization were identified by Fourier transform infrared spectroscopy. The photoluminescence spectrum of the Sm3+ doped cerium oxalate indicated that the Sm3+ ions are optically active in the cerium oxalate matrix. The crystal has a strong and efficient orange red emission with a wavelength peak at 595 nm and hence can be effectively used for optical amplification. Microhardness measurements of the crystal revealed that they belong to the soft material category

Artificially-induced organelles are optimal targets for optical trapping experiments in living cells

Optical trapping supplies information on the structural, kinetic or rheological properties of inner constituents of the cell. However, the application of significant forces to intracellular objects is notoriously difficult due to a combination of factors, such as the small difference between the refractive indices of the target structures and the cytoplasm. Here we discuss the possibility of artificially inducing the formation of spherical organelles in the endoplasmic reticulum, which would contain densely packed engineered proteins, to be used as optimized targets for optical trapping experiments. The high index of refraction and large size of our organelles provide a firm grip for optical trapping and thereby allow us to exert large forces easily within safe irradiation limits. This has clear advantages over alternative probes, such as subcellular organelles or internalized synthetic beads.This research was partly funded by the Spanish Ministry of Education and Science (FIS2010-16104, BFU-2009-07186 and BFU2012-33932) as well as by the regional authorities of Catalonia – ACC1Ó (VALTEC G614828324059231). C. L.-Q. acknowledges an APIF grant from the University of Barcelona and a A. F. an FI grant from the Generalitat de Catalunya (regional authorities of Catalonia).Peer reviewe

Artificially-induced organelles are optimal targets for optical trapping experiments in living cells

Optical trapping supplies information on the structural, kinetic or rheological properties of inner constituents of the cell. However, the application of significant forces to intracellular objects is notoriously difficult due to a combination of factors, such as the small difference between the refractive indices of the target structures and the cytoplasm. Here we discuss the possibility of artificially inducing the formation of spherical organelles in the endoplasmic reticulum, which would contain densely packed engineered proteins, to be used as optimized targets for optical trapping experiments. The high index of refraction and large size of our organelles provide a firm grip for optical trapping and thereby allow us to exert large forces easily within safe irradiation limits. This has clear advantages over alternative probes, such as subcellular organelles or internalized synthetic beads