L'expérience africaine

Due to the pressures of economic and social development, certains underdeveloped countries choose to interpret in their own way the texts of the United Nation's Universal Declaration of Human Rights and give only secondary importance to human rights when they are not perceived as an outright hindrance to development. The consideration given to the subject of Human Rights by the Organization of African Unity in 1979 resulted in the adoption of an African Charter (Banjul) on Human and People's Rights in 1981 which constitutes a decisive step in the evolution of the attitude of African countries in regard to the problem of Human Rights. The author examines the characteristics of this Charter and the efforts of Senegal to incorporate the Charter's principles into its internal law. The author uses the example of Senegal to demonstrate that the imperatives of development are compatible with the respect of Human Rights

Ancient Ancestry of KFDV and AHFV Revealed by Complete Genome Analyses of Viruses Isolated from Ticks and Mammalian Hosts

Alkhurma hemorrhagic fever (AHF) and Kyasanur Forest disease (KFD) viruses both cause serious and sometimes fatal human disease in their respective ranges, Saudi Arabia and India. AHFV was first identified in the mid-1990s and due to its strong genetic similarity to KFDV it has since been considered the result of a recent introduction of KFDV into Saudi Arabia. To gain a better understanding of the evolutionary history of AHFV and KFDV, we sequenced the full-length genomes of 3 KFDV and 16 AHFV. Sequence analyses show a greater genetic diversity within AHFV than previously thought, particularly within the tick population. The phylogeny constructed with these 19 full-length sequences and two AHFV sequences from GenBank indicates AHFV diverged from KFDV almost 700 years ago. Given the presence of competent tick vectors in the regions between and surrounding Saudi Arabia and India and the recent identification of AHFV in Egypt, these results suggest a broader geographic range of AHFV and KFDV, and raise the possibility of other AHFV/KFDV–like viruses circulating in these regions

Carbon Nanotubes in Tissue Engineering

For their peculiar features carbon nanotubes (CNTs) are emerging in many areas of nanotechnology applications. CNT-based technology has been increasingly proposed for biomedical applications, to develop biomolecule nanocarriers, bionanosensors and smart material for tissue engineering purposes. In the following chapter this latter application will be explored, describing why CNTs can be considered an ideal material able to support and boost the growth and the proliferation of many kind of tissues

Root Canal Anatomy of Maxillary and Mandibular Teeth

It is a common knowledge that a comprehensive understanding of the complexity of the internal anatomy of teeth is imperative to ensure successful root canal treatment. The significance of canal anatomy has been emphasized by studies demonstrating that variations in canal geometry before cleaning, shaping, and obturation procedures had a greater effect on the outcome than the techniques themselves. In recent years, significant technological advances for imaging teeth, such as CBCT and micro-CT, respectively, have been introduced. Their noninvasive nature allows to perform in vivo anatomical studies using large populations to address the influence of several variables such as ethnicity, aging, gender, and others, on the root canal anatomy, as well as to evaluate, quantitatively and/or qualitatively, specific and fine anatomical features of a tooth group. The purpose of this chapter is to summarize the morphological aspects of the root canal anatomy published in the literature of all groups of teeth and illustrate with three-dimensional images acquired from micro-CT technology.info:eu-repo/semantics/publishedVersio

Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

Application of carbon nanotubes for cancer treatment

There are two classifications of carbon nanotubes (CNT), firstly single walled carbon nanotubes (SWCNT) and secondly multiwall carbon nanotubes (MWCNT). CNTs have the ability of absorbing near infra-red light and generating heat along with the ability to deliver drugs to the site of action. Different application of CNT has so far studied on the in vitro and in vivo models. This thesis is looking into the application of SWCNT on different in vitro models. These models include human breast cancer cell line (MCF7), human colorectal cancer cell line (HT29 and SW480), human pancreatic cancer cell lines (PANC-1) and mouse fibroblast cell line (3T3). In this research, the functionalization techniques of SWCNT have been investigated. In addition, a detailed observation on the application of SWCNT for thermal treatment and the delivery of anti-cancer drugs to the site of action has been obtained. The thesis also looks into conjugation techniques of other materials to the surface of SWCNT for the purpose of both directing the SWCNT to the site of action and tracking their movement through the cells. Finally yet importantly, a detailed investigation has been performed into the effect of SWCNT size and the conjugation of different functional groups to the SWCNT’s surface on its toxicity. From the results, it can be concluded that treating SWCNT in acid solution and further functionalization with OctaAmmonium-POSS will significantly increase the biocompatibility of the SWCNT. Using functionalized SWCNT could be used for the delivery of anticancer drugs to the site of action and thermal treatment of cancer. It has been demonstrated that attachment of QDs to the SWCNT’s surface can be used for tracking the SWCNT’s movement. Finally, it can be concluded that the smaller length SWCNT with a higher coating concentration of OctaAmmonium-POSS will decrease the toxicity of the SWCNT

Functionalization of single-walled carbon nanotubes and their binding to cancer cells

Seyed Yazdan Madani1, Aaron Tan1, Miriam Dwek2, Alexander M Seifalian1,31UCL Centre for Nanotechnology and Regenerative Medicine, University College London, London, UK; 2Department of Molecular and Applied Biosciences, School of Life Sciences, University of Westminster, London, UK; 3Royal Free Hampstead NHS Trust Hospital, London, UKBackground: Single-walled carbon nanotubes (SWCNTs) have novel properties including their nanoscale size and ease of cellular uptake. This makes them useful for drug delivery, and their photo-thermal effects make them potentially useful in a wide range of applications, particularly the treatment of solid tumors. The poor solubility of SWCNTs has, however, been an issue that may potentially limit the utility of SWCNTs for cancer treatment. Functionalization of the surface of the tubes may be an approach to overcome this problem.Methods: SWCNTs were refluxed in HNO3/H2SO4 (1:3) at 120°C for 120 minutes. Transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), contact angle measurements, and near infrared (NIR) light exposure were used to assess the functionalization process. The attachment of a carbohydrate-binding protein (lectin) labeled with fluorescein isothiocyanate to the functionalized SWCNTs enabled evaluation of the functionalization step via confocal microscopy. The lectin from Helix pomatia, (Helix pomatia agglutinin [HPA]), can detect changes in protein glycosylation associated with aggressive metastatic cancer. The interaction between the lectin HPA alone and HPA conjugated to the functionalized SWCNTs with human breast cancer cells (MCF-7) was measured using a quartz crystal microbalance biosensor.Results: Following the functionalization process, TEM images showed a layer had formed on the surface of the SWCNTs. In the FTIR experiment, results illustrated the presence of the –COOH group on the functionalized SWCNTs. Contact angle measurements showed that upon functionalization the hydrophilicity of the SWCNTs increased. The temperature increase in the liquid (supernatant) surrounding the functionalized SWCNTs following exposure to light in the NIR (808 nm) was greater than for non-functionalized SWCNTs. The biosensor work showed that HPA binds with high affinity (nanomolar range) to human breast cancer cells; HPA-binding properties to MCF-7 cells were retained following conjugation to the functionalized SWCNTs.Conclusion: Treating pure SWCNTs with HNO3/H2SO4 (1:3) at 120°C for 120 minutes is an effective method for functionalization of SWCNTs. HPA linked to SWCNTs is a suitable candidate for the delivery of the functionalized SWCNTs to cancer cells.Keywords: SWCNT, HPA lectin, human breast cancer cell

A new era of cancer treatment: carbon nanotubes as drug delivery tools

Seyed Yazdan Madani1, Naghmeh Naderi1, Oshani Dissanayake1, Aaron Tan1, Alexander M Seifalian1,21Centre for Nanotechnology and Regenerative Medicine, Division of Surgery and Interventional Sciences, University College London, UK; 2Royal Free Hampstead NHS Trust Hospital, London, UKAbstract: Cancer is a generic term that encompasses a group of diseases characterized by an uncontrolled proliferation of cells. There are over 200 different types of cancer, each of which gains its nomenclature according to the type of tissue the cell originates in. Many patients who succumb to cancer do not die as a result of the primary tumor, but because of the systemic effects of metastases on other regions away from the original site. One of the aims of cancer therapy is to prevent the metastatic process as early as possible. There are currently many therapies in clinical use, and recent advances in biotechnology lend credence to the potential of nanotechnology in the fight against cancer. Nanomaterials such as carbon nanotubes (CNTs), quantum dots, and dendrimers have unique properties that can be exploited for diagnostic purposes, thermal ablation, and drug delivery in cancer. CNTs are tubular materials with nanometer-sized diameters and axial symmetry, giving them unique properties that can be exploited in the diagnosis and treatment of cancer. In addition, CNTs have the potential to deliver drugs directly to targeted cells and tissues. Alongside the rapid advances in the development of nanotechnology-based materials, elucidating the toxicity of nanoparticles is also imperative. Hence, in this review, we seek to explore the biomedical applications of CNTs, with particular emphasis on their use as therapeutic platforms in oncology.Keywords: carbon nanotubes, cancer, photothermal therapy, drug delivery, cytotoxicity, near infrare