Reproducible and Bendable SERS Substrates with Tailored Wettability Using Block Copolymers and Anodic Aluminum Oxide Templates.

Surface properties are essential for substrates exhibiting high sensitivity in surface-enhanced Raman scattering (SERS) applications. In this work, novel SERS hybrid substrates using polystyrene-block-poly(methyl methacrylate) and anodic aluminum oxide templates is presented. The hybrid substrates not only possess hierarchical porous nanostructures but also exhibit superhydrophilic surface properties with the water contact angle ≈0°. Such surfaces play an important role in providing uniform enhanced intensities over large areas (relative standard deviation ≈10%); moreover, these substrates are found to be highly sensitive (limit of detection ≈10-12 m for rhodamine 6G (R6G)). The results show that the hybrid SERS substrates can achieve the simultaneous detection of multicomponent mixtures of different target molecules, such as R6G, crystal violet, and methylene blue. Furthermore, the bending experiments show that about 70% of the SERS intensities are maintained after bending from ≈30° to 150°.

Laser-Assisted Nanowetting: Selective Fabrication of Polymer/Gold Nanorod Arrays Using Anodic Aluminum Oxide Templates.

1D polymer nanomaterials have attracted significant interest in recent years because of their unique properties and promising applications in various fields. It is, however, still a challenge to fabricate polymer nanoarrays with desired sizes and controlled morphologies. Here, an unprecedented approach, the laser-assisted nanowetting (LAN) method, to selectively fabricate polymer nanoarrays is presented. Polystyrene (PS) is blended with gold nanorods (AuNRs), which are used to absorb the energy from the laser. After the blend films are brought in contact with AAO templates, the AuNRs at regions shone by the laser beams absorb the energy and heat the surrounding polymer chains, resulting in the formation of PS/AuNRs arrays in selected areas. This work paves a new research direction for developing template-based polymer nanomaterials.

Involvement of Antizyme Characterized from the Small Abalone Haliotis diversicolor in Gonadal Development.

The small abalone Haliotis diversicolor is an economically important mollusk that is widely cultivated in Southern China. Gonad precocity may affect the aquaculture of small abalone. Polyamines, which are small cationic molecules essential for cellular proliferation, may affect gonadal development. Ornithine decarboxylase (ODC) and antizyme (AZ) are essential elements of a feedback circuit that regulates cellular polyamines. This paper presents the molecular cloning and characterization of AZ from small abalone. Sequence analysis showed that the cDNA sequence of H. diversicolor AZ (HdiODCAZ) consisted of two overlapping open reading frames (ORFs) and conformed to the +1 frameshift property of the frame. Thin Layer chromatography (TLC) analysis suggested that the expressed protein encoded by +1 ORF2 was the functional AZ that targets ODC to 26S proteasome degradation. The result demonstrated that the expression level of AZ was higher than that of ODC in the ovary of small abalone. In addition, the expression profiles of ODC and AZ at the different development stages of the ovary indicated that these two genes might be involved in the gonadal development of small abalone.

Spiculisporic acid analogues of the marine-derived fungus, Aspergillus candidus strain HDf2, and their antibacterial activity.

Two novel antibiotic spiculisporic acid analogues, named as spiculisporic acid F (1) and G (2), and two known compounds, (-)-spiculisporic acid (3) and secospiculisporic acid B (4), were isolated by bioactivity-guided fractionation from the fermentation broth of the sea urchin-derived Aspergillus candidus strain HDf2. Their structures were unambiguously established by comprehensive analysis of 1D and 2D NMR, and high-resolution MS spectra, and by comparison with known compounds. Biological experiments demonstrated that compounds 1 and 2 displayed antibacterial activity against Gram-negative Pseudomonas solanacearum and Gram-positive Staphylococcus aureus, but showed no cytotoxicity against SGC-7901 human gastric adenocarcinoma and SPC-A-1 human lung adenocarcinoma tumor cell lines. This is the first critical evidence identifying spiculisporic acid derivatives as a potential bio-control agent for the soil borne pathogen P. solanacearum (E. F. Smith) Smith. These findings provide further insight into the chemical and biological activity diversity of this class of compounds.

Spiculisporic acids B­D, three new γ-butenolide derivatives from a sea urchin-derived fungus Aspergillus sp. HDf2.

Three new γ-butenolide derivatives 1–3, named spiculisporic acids B–D, were isolated from the culture of Aspergillus sp. HDf2, a marine-derived fungus that resides in the sea urchin, Anthocidaris crassispina. The structures of 1–3 were elucidated on the basis of spectroscopic methods, including MS and 2D NMR techniques. Their in vitro cytotoxic activities against two cell lines (SGC-7901, human gastric adenocarcinoma and SPC-A-1, human lung adenocarcinoma) and inhibitory activities against Staphylococcus aureus ATCC 51650 were investigated.

The changing epidemiology of prevalent diagnosed HIV infections in Taiwan, 1984-2005.

By the end of 2005, there were 10,158 reported cases of HIV infections in Taiwan, of them, 2,403 had developed full blown AIDS, and 1,333 had died. It represented an average annual increase of 15% in HIV diagnoses before 2003. The most common route of transmission is through men having sex with men followed by heterosexual contact, while infections through injecting drug use (IDUs) remained low. However, the number of newly reported HIV infections has been rising sharply since 2003, mainly among IDUs. The consequences of this HIV/IDU epidemic include a rapid increase in female HIV/AIDS patients and a decreased mean age of HIV/AIDS cases. Only 2% of patients in the IDU group have been diagnosed with AIDS, suggesting that most IDU cases are in the early stage of HIV infections. HIV/AIDS patients are provided with free medical care by the government in Taiwan, including anti-retroviral treatment. The case fatality rate of AIDS cases declined gradually from 64% in 1996 to 8.9% in 2005. Patients in the IDU group seek medical care less frequently than patients in the sexual contact group. Statistics show that 61.4% of patients in the IDU group did not seek HIV-related medical care, significantly higher compared to the sexual contact group. The Taiwanese government implemented a trial "Harm Reduction Programme," which involved a needle-syringe programme (NSP) and substitution treatment, in August 2005. After 1 year's pilot study, the HIV incidence in cities with NSP decreased from 13.9 to 13.3 per 100,000 persons compared to an incidence increase from 11.5 to 15.3 per 100,000 persons in cities without NSP. We scaled up the programme to cover the whole of Taiwan in July 2006 and are expecting to see the efficacy in the near future.