Preface [Hot Topic: Advances in the Studies of Anti-HIV Drugs - Part II (Guest Editor: S.P. Gupta) ]

Abstract

PrefaceThis Part II of the hot topic issue on Advances in the Studies of Anti-HIV Drugs contains articles mainly related to integrase inhibitors. Presently, the reverse transcriptase (RT) and protease inhibitors, that have been mainly described in Part I, are used in combination to effectively treat the HIV-1 infection. Though this combination therapy has exhibited multiple clinical benefits, the emergence of resistance highlights the need of new anti-HIV agents. Consequently, the researchers focused their attention on new agents able to interfere with additional steps of viral replication and one of them, found to be most crucial, is the integration of the viral DNA into the host cell genome. This step is catalyzed by the enzyme integrase (IN). In the very first article of this issue, Soultrait et al. discuss a combination therapy of RT and IN inhibitors that is based on peptides. Though peptides have long been considered as poor drug candidates, current knowledge on improving the stability and bioavailability of these agents may lead to the effective use of peptides in therapy. Integrase Inhibitors have lately drawn great attention of the chemists and so three most comprehensive articles (2-4), covering all uptodate developments in the area have been fetched. In article 2, Gupta and Nagappa have reviewed all different categories of IN inhibitors, pointing out in each category the important structural features that may be essential for IN inhibition. On the other hand, in article 3, Maurin et al. have presented a detailed study on SARs of these inhibitors and their modes of interaction with the enzyme, and in article 4, Parrill has highlighted even more critically the binding sites, SARs, and future prospectives of these IN inhibitors.In the last article (article 5), Anatasi et al. discuss new antiviral nucleoside prodrugs which have been developed in recent years, so as to improve the efficacy of a given antiviral drug or to overcome several drug deficiencies. Examples of carrierlinked nucleoside prodrugs or nucleoside bioprecursors have been presented and their active mechanism discussed. Thus, this issue covers 5 excellent articles, which I found quite stimulating and informative and hope that the readers will also enjoy reading them. I heartily acknowledge the interest and the zeal that the authors have shown in contributing these articles.

Evolution of Phases, Microstructure, and Surface Roughness during Heat Treatment of Aluminized Low Carbon Steel

“…[13,15] The large number of possible phases in the binary Fe-Al and ternary Fe-Al-Si phase diagram, as well as possible metastable phases, makes the identification of coating phases quite challenging. [15] It is hard to isolate phases [10] and complex diffusion mechanisms associated with time constraints preclude equilibrium resulting in a wide variety of metastable phases. [7] Energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) are often not accurate enough in determining the different phases.…”

“…[7] Energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) are often not accurate enough in determining the different phases. [7,12] For more detailed information, sophisticated methods such as transmission electron microscopy, [12] electron probe analysis, [10] or microdiffraction with a focused XRD [7] are necessary. Hence, the information on some phases is sparse and emphasis was placed only on the aluminum-rich corner of the Fe-Al-Si phase diagram.…”

“…[15] Consequently, silicon reduces the activity coefficient of aluminum in type 1 coatings. [1,5,10] Silicon also builds ternary phases that may slow the diffusion process. Silicon is known to increase dissolution and spalling of the coating layer.…”

Influence of Filler Alloy Composition and Process Parameters on the Intermetallic Layer Thickness in Single-Sided Cold Metal Transfer Welding of Aluminum-Steel Blanks

“…The microstructure details of Figures 8(g) through (j) illustrate that the faceted particles in sample 16 are up to several hundred micrometers in length, but their lengths decrease until they completely disappear at the cutting edge of the steel sheet. The faceted needle-shaped morphology is typical for some ternary Al-Fe-Si phases, [72,73] which may form if iron or aluminum atoms in Al x Fe y phases are partially substituted by silicon atoms during weld bead solidification. [57] This kind of substitution also may cause the formation of particles with the faceted polyhedral morphology occurring in sample 14, as exemplarily marked in Figures 8(b) and (e).…”

Identification of Suitable rhizobacterialspecies for Fluoride Contaminated Areas: A Comparative Growth Kinetics Study

“…From this, least significant difference (LSD) was calculated [24].The value of LSD calculated indicate the minimum difference, which ought to be there for a significant difference to exist between any two groups that were compared. Ranking correlation was applied to identify the best bacterial species in presence of fluoride [11].…”