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This article describes a collaborative research project between the Division on Addiction, Cambridge Health Alliance, a Harvard Medical School Teaching Hospital, and the Integrated Centre on Addiction Prevention and Treatment (ICAPT) of the Tung Wah Group of Hospitals (TWGHs) in Hong Kong. The goal of this research is to better understand the syndrome model of addiction by establishing an epidemiology of addiction treatment seekers across various expressions of addiction (e.g., alcohol and other psychoactive drugs, gambling, sexual behaviors, online gaming). This paper presents initial findings about the demographic and psychological characteristics of three groups of treatment seekers in TWGHs in Hong Kong: (1) a group seeking treatment for chemical expressions of addiction (n = 35); (2) a group seeking treatment for behavioral expressions of addiction (n = 125); and (3) a comparison group seeking services (n = 18) unrelated to addiction. The initial findings identified various common psychological vulnerabilities (i.e., trait anxiety, state anxiety, depression, using emotional support and venting as psychological coping, higher levels of attentional impulsiveness) shared among both the behavioral expression and chemical expression groups, and possible unique psychological characteristics associated with each expression of addiction (e.g., coping mechanisms). These findings provide support for conceptualizing addiction as a syndrome.

In this paper, we investigate the hole transport and electrical properties in a small-molecule organic material N,N′-bis(1-naphthyl)-N,N′-diphenyl-1,1′-biphenyl-4,4′-diamine (NPB), which is frequently used in organic light-emitting diodes. It is shown that the thickness-dependent current density versus voltage (J–V) characteristics of sandwich-type NPB-based hole-only devices cannot be described well using the conventional mobility model without carrier density or electric field dependence. However, a consistent and excellent description of the thickness-dependent and temperature-dependent J–V characteristics of NPB hole-only devices can be obtained with a single set of parameters by using our recently introduced improved model that take into account the temperature, carrier density, and electric field dependence of the mobility. For the small-molecule organic semiconductor studied, we find that the width of the Gaussian distribution of density of states σ and the lattice constant a are similar to the values reported for conjugated polymers. Furthermore, we show that the boundary carrier density has an important effect on the J–V characteristics. Both the maximum of carrier density and the minimum of electric field appear near the interface of NPB hole-only devices.

It has been recently shown that various stress-inducing manipulations in isolated ventricular myocytes may lead to significant remodeling of t-tubules. Osmotic stress is one of the most common complications in various experimental and clinical settings. Therefore, this study was designed to determine the effects of a physiologically relevant type of osmotic stress, hypo-osmotic challenge, to the integrity of t-tubular system in mouse ventricular myocytes using two approaches: (1) electrophysiological measurements of membrane capacitance and inward rectifier (IK1) tail currents originating from K+ accumulation in t-tubules, and (2) confocal microscopy of fluorescent dextrans trapped in sealed t-tubules. Importantly, we found that removal of 0.6 Na (60% NaCl) hypo-osmotic solution, but not its application to myocytes, led to ~27% reduction in membrane capacitance, ~2.5-fold reduction in the amplitude of IK1 tail current and ~2-fold reduction in so-called IK1 ‘inactivation’ (due to depletion of t-tubular K+) at negative membrane potentials – all data being consistent with significant detubulation. Confocal imaging experiments also demonstrated that extracellularly applied dextrans become trapped in sealed t-tubules only upon removal of hypo-osmotic solutions, i.e. during shrinking phase, but not during initial swelling period. In light of these data, relevant previous studies, including those on EC coupling phenomena during hypo-osmotic stress, may need to be reinterpreted and the experimental design of future experiments should take into account the novel findings.

The effect of oxygen on the interface formation between Ca electrode and a poly (9,9-dioctylfluorene) (PFO) film was investigated using x-ray photoelectron spectroscopy (XPS) and ultraviolet photoelectron spectroscopy (UPS). The XPS results indicated that strong interaction between Ca and C occurred and the lowest unoccupied molecular orbitals (LUMO's) of PFO were affected upon a submonolayer Ca deposition. After ${\mathrm{O}}_{2}$ exposure, the interaction between Ca and C was reduced and the LUMO of PFO was partially recovered. However, too much ${\mathrm{O}}_{2}$ exposure $(g{10}^{5}\mathrm{L}$ in our experiments) would again deteriorate the original LUMO and result in a very wide band gap, which might be due to changes in the chemical structures of PFO in the Ca-doped region after extra ${\mathrm{O}}_{2}$ exposure. The UPS results confirmed that the deformed UPS spectrum after Ca deposition can be partially recovered and the Ca-induced bipolaron states in the former forbidden energy gap could be removed upon ${\mathrm{O}}_{2}$ exposure.

The purpose of this study is to investigate the difference between students with more experience and students with less experience on the confidence in using technology for learning in Hong Kong higher education. A survey methodology was employed and 211 questionnaires were collected in a Hong Kong university. The finding shows that students with more experience are found to have more confidence in using technology for learning than students with less experience.

Extensive burn wound coverage remains a major problem in acute and reconstructive stages due to shortage of autologous skin donor sites. Many reports have described successful coverage of extensive burn wounds by using cultured keratinocytes sheet graft alone or overlaying a glycosaminoglycan substrate, allodermis or xenodermis. In our experience, the use of Boyce and Ham's serum-free medium made the preparation of keratinocyte cultures simple and the cell growth was prompt. In this study, one of the supplements in Boyce's culture medium, the bovine pituitary extract (BPE at concentration of 140 micrograms/ml), was replaced by different concentrations of fresh frozen porcine pituitary extract (PPE). The protein concentration of the original preparation of PPE was also 140 micrograms/ml but in which 375 +/- 21 pg/ml (1/10 dilution) of platelet-derived growth factor (PDGF) was detected by immunoassay (PDGF ELISA). Our results proved that PPE is an ideal supplement for the in vitro growth of keratinocytes, and when its protein concentration is 350 micrograms/ml will induce a significant keratinocyte growth by day 9 when compared to the regular BPE and also to the other concentrations of PPE (P0.05).

Haepatocellular carcinoma (HCC) is the most common primary liver malignancy, representing the fifth most common cancer in the world. Without treatment, the median survival of HCC patients has been reported to be 8 weeks from symptomatic presentation. Transarterial chemoembolisation is widely used to manage unresectable HCCs. However, when a tumour is large or locates near the liver capsule, it may receive supplies from vessels other than hepatic arteries. In this paper, we discuss the anatomy of possible extrahepatic collateral arterial supplies of HCCs.

Ultraviolet photoelectron spectroscopy has been applied to the investigation of modified hole injection barriers in organic light-emitting devices (OLEDs). Different from those reported previously, the indium tin oxide (ITO) surface treated in situ by oxygen plasma possesses a work function of 5.2 eV, and the organic ITO interface thereafter formed shows a 0.5 eV smaller hole injection barrier compared to that on untreated ITO. Insertion of an ultrathin SiO2 layer between the organic and ITO results in a similar reduction of the barrier. This indicates that improved hole injection favors efficient operation of OLEDs, as manifested by enhanced efficiency by the SiO2 insertion.

The interaction between magnesium (Mg) and tris(8-hydroxy-quinoline) aluminum (Alq3) has been studied using high-resolution electron energy-loss spectroscopy (HREELS). It was found that deposition of magnesium on the Alq3 film gave rise to clear changes in the HREELS spectra. The changes are attributed to the weakly bounded Mg atoms on the Alq3 layer. Interestingly, for a given amount of magnesium (Mg to Al atoms ratio=3) on Alq3 film, remarkable changes were observed in the HREELS spectra when the sample was heated. A loss peak at 81 meV, which was assigned to Mg–O stretch mode, appeared upon annealing and increased in intensity as the annealing temperature increased up to about 360 K. This suggested that the diffusion of Mg atoms into the Alq3 layer and the reaction between Mg and Alq3 molecule occurred at the temperature range investigated. The present work has provided direct evidence for the strong interaction between magnesium and Alq3.

Spinal cord compression is a very debilitating condition and could be secondary to many causes. Urgent magnetic resonance (MR) imaging of the spine is crucial in making the diagnosis and guiding further management. Our objectives were to assess the nature of MR imaging requests, the diagnostic yield, and the subsequent management according to relevant MR imaging findings.We focused on all the urgent MR imagings of the spine conducted from July 1, 2007 to December 31, 2007. Clinical data, including the demographical information, presenting symptoms, radiological diagnosis, waiting time for MR imaging and treatment, was reviewed.A total of 33 cases of urgent MR imaging of the spine were performed. Patients were aged 29-85 years, with 18 males and 15 females. Most of them (84.8 percent) presented with neurological symptoms. 84 percent of the MR imaging was performed within 24 hours. 76 percent of the examinations yielded significant cord compression, of which 56 percent were due to vertebral metastasis, while others were due to epidural haematoma (12 percent), infective spondylodiscitis (8 percent), vertebral fracture (8 percent) and disc herniation (16 percent). Of the vertebral metastasis patients, 43 percent had one region imaged. 64 percent of the cord compression patients received surgical treatment or radiotherapy, with a mean waiting time of 1.7 days.The urgent MR imaging spine service was able to react promptly with a high diagnostic yield. One-third of the patients with vertebral metastasis had multiple levels involved, and imaging of the whole spine would be useful.

To determine the effects of triptolide (TP) on the expression of interleukin-18 (IL-18) and its receptor in phorbol 12-myristate 13-acetate (PMA)-stimulated rheumatoid arthritis synovial fibroblasts (RASF).RASF were obtained from the synovial tissue of patients with RA. RASF were pretreated with TP (0~100 ng/ml) for 2 h before stimulation with PMA (50 ng/ml). The bioactivity of IL-18 in the supernatant was detected based on IFN-gamma secretion from IL-18-responding human myelomonocytic KG-1 cells. IL-18 level was analyzed by ELISA. In situ expression of IL-18Ralpha was determined by immunofluorescence assay. To estimate the protein and mRNA expression of IL-18 and IL-18Ralpha in RASF, western blot and quantitative RT-PCR were performed. Nuclear factor-kappaB (NF-kappaB) activity in the whole-cell extract of treated RASF was also measured using an ELISA-based method.TP effectively inhibited the bioactivity of IL-18 in PMA-stimulated RASF. The expression of IL-18 and IL-18R at protein and gene levels was reduced by TP. NF-kappaB activity in PMA-stimulated RASF was profoundly suppressed by TP. These effects showed a high correlation with TP concentration (0~100 ng/ml).TP effectively inhibited the expression of IL-18 and its receptor in PMA-stimulated RASF. These results suggest a mechanism of TP in RA therapy.

Small vessels gradually reappear within the esophageal wall after endoscopic injection sclerotherapy or endoscopic variceal ligation, which causes late recurrent bleeding. Additional ligation or a small amount of sclerotherapy of these thin and serpentine vessels is sometimes difficult to perform, and stenosis of the esophagus sometimes occurs after a small amount of sclerotherapy. In this study we attempted endoscopic photodynamic therapy on newly visible vessels and evaluated its ability to prevent recurrent bleeding. Fourteen patients with newly visible vessels within the esophageal wall were enrolled. All patients had esophageal varices secondary to hepatitis B and had their varices eliminated through endoscopic sclerotherapy before neovascularization. Seven patients received photodynamic therapy, and seven patients served as the control group. In the photodynamic therapy group, intravenous injection of 5 mg/kg of hematoporphyrin monomethyl ether was given and immediately followed by endoscopic irradiation of the newly visible vessels by copper vapor laser for 40 min with a power density of 150 mW/cm2. Endoscopic examination was performed 3 months later to evaluate the therapeutic effect. The duration of non-bleeding was compared between the two groups. The number of newly visible vessels was found to have decreased after photodynamic therapy when compared with the control group (P < 0.001). Kaplan–Meier analyses demonstrated a longer period of non-bleeding in the photodynamic therapy group. The recurrent bleeding rate in the photodynamic therapy (PDT) group was lower than that in the control group (P = 0.027). One patient in the photodynamic therapy group suffered from facial dermatitis from shining direct light. Endoscopic photodynamic therapy seemed to be effective in the elimination of esophageal newly visible vessels and the prevention of recurrent bleeding.

To detect the expression of glutathione S-transferase Pi(GST-pi), multidrug resistance-associated protein (MRP), lung-resistance protein(LRP), multidrug resistance gene1 (MDR1) and MGr1 antigen(MGr1-Ag) in the patients with primary gastric cancer and without any prior chemotherapy and to evaluate the correlations between them.The expression of GST-pi, MRP, LRP and MDR1 in cancer tissue and the adjacent non-cancerous tissue from 50 patients was examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR). The expression of MGr1-Ag in these tissues was also examined by immunohistochemistry.The positive rate of GST-pi mRNA, MRP mRNA, LRP mRNA, MDR1mRNA and MGr1-Ag in gastric cancer tissue was 36.00%, 12.00%, 10.00%, 10.00% and 18.00% respectively. The overall positive rate of their expression was 58.00%. Clinicopathological factors were not significantly related to their expression. No significant correlation was observed between these markers.These MDR markers are differently over-expressed and no coexpression exists in gastric cancer. MGr1-Ag was a novel MDR protein.

The effect of minor addition of 3d transition metals on the formation enthalpy (△H) and electronic structure of MgH2 have been studied using first-principle calculations, and considering the phonon-calculated zero point energy. The results indicate that the partial substitution of Mg atoms by 3d transition metal atoms increases the formation enthalpy of MgH2. Both formation enthalpy and Mulliken population analysis showed that the ability to destabilize MgH2 generally increases with the atomic number, except Mn and Zn, which have half-filled and completely filled 3d orbital states. The destabilization of MgH2 by partially alloying 3d elements was due to relatively stronger covalent bonds between 3d elements and the H atom, and a weaker ionic bond between Mg and H in the alloyed material with respect to pure MgH2. Based on electronic structure analyses, MgH2 and MgH2 alloyed with Ti, Fe, and Zn show no spin magnetism, while MgH2 alloyed with Sc, V, Cr, Mn, Co, Ni, and Cu show spin magnetism. In the MgH2-3d...

Advanced primary hepatic carcinoma was treated in 110 patients by percutaneous transhepatic arterial chemoembolization (TAE) from January 1987 to October 1989 according to Seldinger's protocol with mitomycin C, Adriamycin or carboplatin and 40% iodized oil. The treatment was given once every 4-12 weeks and the number of treatment for each patient varied from 2 to 19 depending on patients' condition and response. Of the 110 patients, 20 survived3 years, among which 7 survived4 years and 4 survived5 years. Following treatment, a greater than 50% reduction of tumor size was observed in 13 cases and a decrease in AFP to normal level in 12 cases. Seven patients were treated with TAE followed by tumor resection and, 2 patients were treated with TAE due to recurrence after tumor resection 11 patients were treated with TAE alone. The mean survival period was 53.1 and 43.5 months, respectively. TAE is considered as the first choice of palliative treatment for patients with advanced hepatic carcinoma. Factors that might influence the result of TAE treatment are discussed.

Controlled-release polymeric needle devices containing adriamycin HCL (ADH) were investigated by an in vitro dissolution study in normal saline solution and an in vivo antitumor activity in C3H mice bearing mammary carcinoma and nude mice bearing brain tumor. HPMC was used as a release rate regulator. The ADH released from needle devices was controlled by the types of polymer used and the addition of HPMC. EVA needle devices exhibit a zero order release behavior better than that of PLA needle devices. Tumor growth was markedly inhibited by treatment with needle devices after locally inserted into the solid tumor. The rank of antitumor activity of the needle devices is EVA > PLA > EVA-HPMC > PLA-HPMC. No significant changes in body weight of mice after treatment were found in treated groups as compared to controlled groups. The preliminary results of our study suggest that needle device dosage form shows a controlled release behavior and may be applicable as a drug carrier for delivery of antitumor drug in...

Controlled-release polymeric needle devices containing adriamycin HCL (ADH) were investigated by an in vitro dissolution study in normal saline solution and an in vivo antitumor activity in C3H mice bearing mammary carcinoma and nude mice bearing brain tumor. HPMC was used as a release rate regulator. The ADH released from needle devices was controlled by the types of polymer used and the addition of HPMC. EVA needle devices exhibit a zero order release behavior better than that of PLA needle devices. Tumor growth was markedly inhibited by treatment with needle devices after locally inserted into the solid tumor. The rank of antitumor activity of the needle devices is EVA greater than PLA greater than EVA-HPMC greater than PLA-HPMC. No significant changes in body weight of mice after treatment were found in treated groups as compared to controlled groups. The preliminary results of our study suggest that needle device dosage form shows a controlled release behavior and may be applicable as a drug carrier for delivery of antitumor drug in cancer chemotherapy.

Two types of polymeric needle devices (reservoir type and matrix type) were prepared. The release behavior and mechanism of adriamycin HCl from these needle devices were investigated and deduced. Adriamycin HCl released from reservoir type needle devices exhibited a zero order release kinetic, but a Higuchi membrane-diffusion controlled model was shown in matrix type needle devices. A lag time and burst effect were obtained in reservoir type and matrix needle devices, respectively. The release of adriamycin HCl from these needle devices was controlled and can be monitored by adding a hydrophilic or hydrophobic additive.

The surface of poly (9,9-dioctylfluorene) (PFO) film was modified by 1.0 keV Ar+ irradiation with a dose of 6.5×1014 ions/cm2 prior to Ca deposition. Ultraviolet and x-ray photoelectron spectroscopic studies indicated that the modified surface could effectively block Ca diffusion into the PFO film and prevent the formation of doping-induced bipolaron states in the former forbidden energy gap. As a result, a sharper metal contact on the surface of the PFO film could be formed, compared to that on the surface without Ar+ irradiation. The results suggest that the judicial surface modification of polymer surfaces may be useful for the improvement of metal/polymer contacts and thus device performance.