Shining light on nanotechnology to help repair and regeneration

Phototherapy can be used in two completely different but complementary therapeutic applications. While low level laser (or light) therapy (LLLT) uses red or near-infrared light alone to reduce inflammation, pain and stimulate tissue repair and regeneration, photodynamic therapy (PDT) uses the combination of light plus non-toxic dyes (called photosensitizers) to produce reactive oxygen species that can kill infectious microorganisms and cancer cells or destroy unwanted tissue (neo-vascularization in the choroid, atherosclerotic plaques in the arteries). The recent development of nanotechnology applied to medicine (nanomedicine) has opened a new front of advancement in the field of phototherapy and has provided hope for the development of nanoscale drug delivery platforms for effective killing of pathological cells and to promote repair and regeneration. Despite the well-known beneficial effects of phototherapy and nanomaterials in producing the killing of unwanted cells and promoting repair and regeneration, there are few reports that combine all three elements i.e. phototherapy, nanotechnology and, tissue repair and regeneration. However, these areas in all possible binary combinations have been addressed by many workers. The present review aims at highlighting the combined multi-model applications of phototherapy, nanotechnology and, reparative and regeneration medicine and outlines current strategies, future applications and limitations of nanoscale-assisted phototherapy for the management of cancers, microbial infections and other diseases, and to promote tissue repair and regeneration.     

Identification and characterization of a pig FKBP5 gene with a novel expression pattern in lymphocytes and granulocytes

Abstract

The immunophilins are an important group of regulatory molecules in the immune system. FKBP5, expressed throughout mammals and in fish and birds, functions in both physiological and pathogenic pathways, including innate immunity and steroid-based diseases. In this study, we cloned the first porcine FKBP5 from Rongchang pig by the rapid amplification of cDNA ends technique. The full-length cDNA is 4097?bp, with an open reading frame of 1371?bp that codes for a 457-aa protein. Western blotting detected the porcine FKBP5 protein at highest levels in thymus, followed by spleen and lung. Immunohistochemistry detected the porcine FKBP5 protein in lymphocytes and granulocytes of the blood, and flow cytometry identified greater expression in unactivated (vs. activated) T lymphocytes. Finally, the expression level of porcine FKBP5 in the granulocytes was found to decline significantly from the time of birth to one-year-old. These collective data suggest that the newly identified porcine FKBP5 may function in activation of T cells in pig and in innate immunity in the newborn pig in particular.     

Synthesis of Zidovudine Derivatives with Anti-HIV-1 and Antibacterial Activities

Twelve novel zidovudine derivatives were prepared by modifying 5 ′-hydroxyl group of sugar moiety (1–8) and 5-methyl group of thymidine nucleus (9–12) and characterized spectrally. The compounds were evaluated for anti-HIV-1, antitubercular and antibacterial activities. Compound (3-azido-tetrahydro-5- (3,4-dihydro-5-methyl-2,4-dioxopyrimidin- 1 (2H)-yl) furan-2-yl)methyl 7- (4- (2-phenylacetoyloxy) -3,5- dimethylpiperazin-1-yl) -5- (2-phenylacetoyloxyamino) -1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (5) was found to be the most potent anti-HIV-1 agent with EC₅₀ of 0.0012 μM against HIV-1_IIIB and CC₅₀ of 34.05 μM against MT-4 with selectivity index of 28,375. Compound 5 inhibited Mycobacterium tuberculosis with MIC of 1.72 μM and inhibited four pathogenic bacteria with MIC of less than 1 μM.     

Analysis of the frequency of inheritance of transposed Ds elements in Arabidopsis after activation by a CaMV 35S promoter fusion to the Ac transposase gene

The Ac/Ds transposon system of maize shows low activity in Arabidopsis. However, fusion of the CaMV 35S promoter to the transposase gene (35S::TPase) increases the abundance of the single Ac mRNA encoded by Ac and increases the frequency of Ds excision. In the experiments reported here it is examined whether this high excision frequency is associated with efficient re-insertion of the transposon. This was measured by using a Ds that carried a hygromycin resistance gene (HPT) and was inserted within a streptomycin resistance gene (SPT). Excision of Ds therefore gives rise to streptomycin resistance, while hygromycin resistance is associated with the presence of a transposed Ds or with retention of the element at its original location. Self-fertilisation of most individuals heterozygous for Ds and 35S::TPase produced many streptomycin-resistant (strep^r) progeny, but in many of these families a small proportion of strep^r seedlings were also resistant to hygromycin (hyg^r). Nevertheless, 70% of families tested did give rise to at least one strep^r, hyg^r seedling, and over 90% of these individuals carried a transposed Ds. In contrast, the Ac promoter fusion to the transposase gene (Ac::TPase) produced fewer strep^rhyg^r progeny, and only 53% of these carried a transposed Ds. However, a higher proportion of the strep^r seedlings were also hyg^r than after activation by 35S::TPase. We also examined the genotype of strep^r, hyg^r seedlings and demonstrated that after activation by 35S::TPase many of these were homozygous for the transposed Ds, while this did not occur after activation by Ac::TPase. From these and other data we conclude that excisions driven by 35S::TPase usually occur prior to floral development, and that although a low proportion of strep^r progeny plants inherit a transposed Ds, those that do can be efficiently selected with an antibiotic resistance gene contained within the element. Our data have important implications for transposon tagging strategies in transgenic plants and these are discussed.     

Synthesis and biological evaluation of novel dihydro-aryl/alkylsulfanyl-cyclohexylmethyl-oxopyrimidines (S-DACOs) as high active anti-HIV agents

A novel dihydro-aryl/alkylsulfanyl-cyclohexylmethyl-oxopyrimidines (S-DACOs) combinatory library was synthesized and evaluated with C8166 cells infected by the HIV-1_IIIB in vitro, using Nevirapine (NVP) and Zidovudine (AZT) as positive control. The anti-HIV screening results revealed that C-6-cyclohexylmethyl substituted pyrimidinones possessed higher selective index than its 6-arylmethyl counterparts. Compounds 1g, 1c, 1e and 1b showed potent anti-HIV activities with EC₅₀ values of 0.012, 0.025, 0.088 and 0.162 nM, respectively.     

Conductive and Catalytic Triple‐Phase Interfaces Enabling Uniform Nucleation in High‐Rate Lithium–Sulfur Batteries

Rechargeable lithium–sulfur batteries have attracted tremendous scientific attention owing to their superior energy density. However, the sulfur electrochemistry involves multielectron redox reactions and complicated phase transformations, while the final morphology of solid‐phase Li₂S precipitates largely dominate the battery's performance. Herein, a triple‐phase interface among electrolyte/CoSe₂/G is proposed to afford strong chemisorption, high electrical conductivity, and superb electrocatalysis of polysulfide redox reactions in a working lithium–sulfur battery. The triple‐phase interface effectively enhances the kinetic behaviors of soluble lithium polysulfides and regulates the uniform nucleation and controllable growth of solid Li₂S precipitates at large current density. Therefore, the cell with the CoSe₂/G functional separator delivers an ultrahigh rate cycle at 6.0 C with an initial capacity of 916 mAh g^?1 and a capacity retention of 459 mAh g^?1 after 500 cycles, and a stable operation of high sulfur loading electrode (2.69–4.35 mg cm^?2). This work opens up a new insight into the energy chemistry at interfaces to rationally regulate the electrochemical redox reactions, and also inspires the exploration of related energy storage and conversion systems based on multielectron redox reactions.     

Singing behavior and singing functions of black‐crested gibbons (Nomascus concolor jingdongensis) at Mt. Wuliang,central Yunnan,China

We used data on loud duetted and solo songs collected from one habituated polygynous group of black‐crested gibbons (Nomascus concolor jingdongensis) on Mt. Wuliang, Yunnan, to test several hypotheses about the functions of these songs. The major functions proposed for loud gibbon songs include resource defense, mate defense, pairbonding, group cohesion and mate attraction. Duet bouts are generally initiated by adult males, who select the highest trees near to ridges or on steep slopes as singing trees. Such trees facilitate voice transmission and inter‐group communication. Singing trees tended to be located near important food patches and sleeping sites, which supports the resource defense hypothesis. The adult male and two adult females always sang interactively, alternating male phrases with the females' stereotyped great calls, to produce the duets, and females rarely produced great calls if they were more than 30 m from the male. The two females usually produced great calls synchronously during the duet, especially when they were close together. These features support both the mate defense and pairbonding hypotheses. The number of great calls and their degree of synchrony transmit information about spatial relationships and possibly pairbond strength to members to neighboring groups and floating animals. During or after the duet bouts, the adult females and juvenile moved toward to the adult male; and group members maintained a close spatial relationship, which supports the group cohesion hypothesis. Other incidents observed suggest a mate competition role for duets. The adult male always sang when the females started duetting with the subadult male. The subadult male sang solo bouts, but they were not more frequent or longer than bouts initiated by the adult male. Although mate attraction is the likely function of subadult solos, it was not convincingly demonstrated. In conclusion, all hypotheses concerning the function of singing are supported by at least some of the data, and none can be excluded. Am. J. Primatol. 71:539–547, 2009. © 2009 Wiley‐Liss, Inc.