Explore the vast range of titles available.

We have developed a chlorine based reactive ion etching process to yield randomly oriented anisotropic nanostructures that render the titanium metal surface ‘black’ similar to that of black silicon. The surface appears black due to the nanostructures in contrast to the conventional shiny surface of titanium. The nanostructures were found to kill bacteria on contact by mechanically rupturing the cells as has been observed previously on wings of certain insects. The etching was optimized to yield nanostructures of ≈1 μm height for maximal bactericidal efficiency without compromising cytocompatibility. Within 4 hours of contact with the black titanium surface, 95% ± 5% of E. coli, 98% ± 2% of P. aeruginosa , 92% ± 5% of M. smegmatis and 22% ± 8% of S. aureus cells that had attached were killed. The killing efficiency for the S. aureus increased to 76% ± 4% when the cells were allowed to adhere up to 24 hours. The black titanium supported the attachment and proliferation of human mesenchymal stem cells and augmented osteogenic lineage commitment in vitro . Thus, the bioinspired nanostructures on black titanium impart multi-biofunctional properties toward engineering the next-generation biomaterials for orthopedic implants.

Owing to the unique physical, chemical, mechanical and electrical properties, graphene and its derivatives have been extensively researched for diverse biomedical applications including in tissue engineering since the past decade. Tunable chemical functionalities of graphene oxide (GO), a graphene derivative, allow easy surface functionalization. Functionalization of GO with poly(ethylene glycol) (PEG) (PEG-GO) has received significant attention as it offers superior solubility, stability, and biocompatibility. Besides being an attractive candidate for drug delivery, PEG-GO can aid in the attachment, proliferation, and differentiation of stem cells, thereby augmenting tissue engineering. PEG-GO has shown excellent antibacterial efficacy, which could be an added advantage to minimize implant-associated infections. This review describes the synthesis techniques, properties, and biological potential of PEG-GO towards mammalian and bacterial cells. Studies wherein these nanomaterials have been explored for engineering various tissues are reviewed along with future opportunities in this field.

Metal additive manufacturing processes offer unique opportunities for the biomedical industry owing to their ability to produce custom-designed implants with near-net shape and intricate geometry. Co–Cr alloys are among the most popular metallic biomaterials due to their excellent resistance to both corrosion and wear. Several studies have been reported in recent years on studying the processing-structure–property relationships in additively manufactured Co–Cr alloys. However, there is a significant gap in knowledge of critical issues such as the microstructural features and properties of additively manufactured parts as well as the role of the processing parameters and post-manufacturing treatments. The performance of the additively manufactured Co–Cr alloys for biomedical applications such as fatigue, wear, corrosion, and the biological response is poorly characterized as yet. This article presents an overview of the existing literature available on additively manufactured Co–Cr alloys and identifies challenges and opportunities for their use in biomedical implants. Graphic abstract

Here, we investigate the effect of high-pressure torsion (HPT), a severe plastic deformation process, on the mechanical properties, corrosion, and cytotoxicity of Mg–6Zn–0.2Ce alloy, a candidate material for bioresorbable bone implants. This alloy was processed by quasi-constrained HPT by applying a pressure of 6 GPa at room temperature for 1, 2, and 5 turns. Samples processed to two turns of HPT showed the smallest grain size, the highest strength that was approximately five times higher than the as-received coarse-grained sample and a reduction in the ductility. Electrochemical impedance spectroscopy and potentiodynamic polarization demonstrated the highest corrosion resistance for the Mg-alloy processed for two turns of HPT; however, accelerated degradation due to pitting corrosion was observed after immersion in simulated body fluid for 3 days. Nevertheless, all HPT-processed samples showed lower corrosion rates in all corrosion tests compared to their annealed counterparts. Finally, cell culture revealed good cytocompatibility without any noticeable changes in cytotoxicity following HPT processing. Overall, HPT for two turns showed enhanced strength and reduced corrosion rates without loss in cytocompatibility for the Mg–6Zn–0.2Ce alloy, making it a promising strategy to enhance the performance of the alloy as a bioresorbable orthopedic biomaterial. This work highlights the potential of HPT as a viable technique to improve the biomedical performance of Mg alloys for engineering next-generation biomedical implants.

The aim of this work was to study tribological behavior and biological response of selective laser-melted Ti6Al7Nb-based TiB-reinforced composites. The synergistic properties achieved by different content of the in situ TiB phase (1.5 and 3.0 wt%) enhanced the wear resistance of Ti6Al7Nb. Abrasion and microplastic deformations were the predominant wear mechanisms observed in these composites. The contact angle of simulated body fluid on TiB-reinforced sample surfaces revealed that the surfaces were moderately hydrophilic. In vitro cell studies with pre-osteoblasts confirmed the non-toxic nature of all the three samples (matrix—Ti6Al7Nb, 1.5, and 3.0 wt% TiB composites) studied here. The enhanced wear resistance coupled with its non-toxic nature and good cell proliferation demonstrated that the Ti6Al7Nb–TiB composites are promising candidates for the fabrication of biomedical implants. In addition, the results demonstrate that Ti6Al7Nb composites can be easily fabricated by solidification-based additive manufacturing processes. Graphical abstract

Globally, millions of bone graft procedures are being performed by clinicians annually to treat the rising prevalence of bone defects. Here, the study designed a fucoidan from Sargassum ilicifolium incorporated in an osteo-inductive scaffold comprising calcium crosslinked sodium alginate-nano hydroxyapatite-nano graphene oxide (Alg-HA-GO-F), which tends to serve as a bone graft substitute. The physiochemical characterization that includes FT-IR, XRD, and TGA confirms the structural integration between the materials. The SEM and AFM reveal highly suitable surface properties, such as porosity and nanoscale roughness. The incorporation of GO enhanced the mechanical strength of the Alg-HA-GO-F. The findings demonstrate the slower degradation and improved protein adsorption in the fucoidan-loaded scaffolds. The slow and sustained release of fucoidan in PBS for 120 h provides the developed system with an added advantage. The apatite formation ability of Alg-HA-GO-F in the SBF solution predicts the scaffold’s osteointegration and bone-bonding capability. In vitro studies using C3H10T1/2 revealed a 1.5X times greater cell proliferation in the fucoidan-loaded scaffold than in the control. Further, the results determined the augmented alkaline phosphatase and mineralization activity. The physical, structural, and enriching osteogenic potential results of Alg-HA-GO-F indicate that it can be a potential bone graft substitute for orthopedic applications.

Background: Asymptomatic and mild form of the neurocognitive disorder in individuals with human immunodeficiency virus infection is still prevalent and a chief problem worldwide although the severity of the neurocognitive complications is decreasing after the introduction of combined highly active antiretroviral therapy. Aim: To study language and executive dysfunction of HIV patients in Clinical Stage 1 in an industrial scenario in Western Maharashtra as compared to healthy controls. Material and Methods: The Wisconsin card sorting test and Addenbrooke cognitive scale were done to check for executive function and language, respectively, and compared to age- and gender-matched HIV-negative controls. Results: Both the results of the WCST and Addenbrooke cognitive scale showed a decline in scores in the cases as compared to the controls overall. The distribution of cases as per the gender showed no significant difference, whereas there was a significant difference as per the age. Conclusion: In asymptomatic HIV patients, there is a decline in executive function and language as compared to the healthy controls. As most of the individuals were employed, there is a need to assess their neurocognitive function regularly as the progress of the illness can be monitored and cognitive training can be advised in these HIV-positive patients, which will not only benefit the individuals but the industrial sector in the long run as well.

In 2016–17, the Galactic transient black hole candidate GRS 1716-249 exhibited an outburst event after a long quiescence period of almost 23 years. The source remained in the outbursting phase for almost 9 months. We study the spectral and temporal properties of the source during this outburst using archival data from four astronomy satellites, namely MAXI, Swift, NuSTAR and AstroSat. Initial spectral analysis is done using combined disk black body and power-law models. For a better understanding of the accretion flow properties, we studied spectra with the physical two component advective flow (TCAF) model. Accretion flow parameters are extracted directly from the spectral fits with the TCAF model. Low frequency quasi periodic oscillations are also observed in the Swift/XRT and AstroSat/LAXPC data. From the spectral fit, we also estimate the probable mass of GRS 1716-249 to be in the range of 4.50–5.93M⊙ or 5.01−0.51+0.92M⊙. Refitting of all spectra is done by freezing the mass at its average value. An insignificant deviation of the TCAF model parameters is observed. From the nature of the variation of the newly fitted spectral and temporal properties, we find that the source stays in only the harder (hard and hard-intermediate) states during the outburst. It does not make a transition to the softer states which makes it a ‘failed’ outburst.

ABSTRACT Mental disorders are major contributors to global burden of disease measured in Disability Adjusted Life Years (7% of all disease burden in 2017). Large treatment gaps for these disorders exist in all parts of the world. In India, overall treatment gap for mental disorders was found to be 83%. Women, children and adolescents, ethnic minorities, LGBTQ+ community, elderly and those living in remote and inaccessible areas have disproportionately higher rates of mental illness. They face unique and characteristic barriers to access to mental healthcare which increases treatment gap. These gaps have persisted despite global efforts and interventions to mitigate these barriers. Hence, there is a need to find alternatives to reduce mental health gap in these groups. Positive Mental Health interventions focuson well-being and health promoting activities, rather than on illness. The potential role of these interventions in promoting mental health and reducing treatment gap has been explored in this article.