Electrically injected 1.64µm emitting In0.65Ga0.35As 3-QW laser diodes grown on mismatched substrates by MOVPE.

We report the characteristics of the strained In0.65Ga0.35As triple quantum well (QW) diode lasers grown by metalorganic vapor phase epitaxy (MOVPE) on lattice-mismatched substrates such as GaAs or Si, by utilizing InP metamorphic buffer layers (MBLs) in conjunction with InAs nanostructure-based dislocation filters. As the lattice-mismatch between the substrate and InP MBL increases, higher threshold current densities and lower slope efficiencies were observed, together with higher temperature sensitivities for the threshold current and slope efficiency. Structural analysis performed by both high-resolution X-ray diffraction (HR-XRD) and transmission electron microscopy indicates graded and/or rougher QW interfaces within the active region grown on the mismatched substrate, which accounts for the observed devices characteristics.

Do concordances of social support and relationship quality predict psychological distress and well-being of cancer patients and caregivers?

This study examined concordances of cancer patients' received and caregivers' provided support and dyadic relationship quality, and their predictive utility in prospective psychological distress and well-being. A total of 83 Chinese cancer patient-caregiver dyads were recruited in two government-funded hospitals in Hong Kong. Participants reported received (patient)/provided (caregiver) emotional and instrumental support and dyadic relationship quality within 6 months after diagnosis (T1), and anxiety and depressive symptoms, positive affect and life satisfaction at both T1 and 6-month follow-up (T2). We hypothesised that concordances at T1 would predict lower psychological distress and higher psychological well-being among both patients and caregivers at T2. Concordances were indicated by Gwet's AC2 scores (possible range = -1.00 to 1.00) and as follows: emotional support: M = 0.92, SD = 0.12, range = 0.25-1.00; instrumental support: M = 0.92, SD = 0.16, range = 0.08-1.00; and relationship quality: M = 0.63, SD = 0.27, range = -0.31 to 1.00. Hierarchical multiple regressions revealed that T1 concordances of perceived emotional and instrumental support and dyadic relationship quality positively predicted T2 anxiety symptoms [F(9, 74) = 6.725, ∆R2  = .031, p < .001)] and state positive affect [F(9, 74) = 3.436, ∆R2  = .042, p = .001)], whereas inversely predicted T2 depressive symptoms [F(9, 74) = 4.189, ∆R2  = .042, p < .01)]. Significant associations were found only among caregivers, but not patients.

Danggui Buxue Tang, Chinese Herbal Decoction Containing Astragali Radix and Angelicae Sinensis Radix, Induces Production of Nitric Oxide in Endothelial Cells: Signaling Mediated by Phosphorylation of Endothelial Nitric Oxide Synthase.

Danggui Buxue Tang, an ancient Chinese herbal decoction containing Astragali Radix and Angelicae Sinensis Radix at the weight ratio of 5:1, is used to mitigate menopausal syndromes in women. The pharmacological properties of Danggui Buxue Tang have been illustrated in bone development, blood enhancement, and immune stimulation. Here, we extended the possible pharmacological role of Danggui Buxue Tang in cardiovascular function. In cultured human umbilical vein endothelial cells, the application of Danggui Buxue Tang induced the release of nitric oxide and the phosphorylation of endothelial nitric oxide synthase and Akt kinase in time- and dose-dependent manners. The robust activation of nitric oxide signaling, however, required the boiling of Astragali Radix and Angelicae Sinensis Radix together, i.e., as Danggui Buxue Tang instead of other herbal extracts. The Danggui Buxue Tang-induced phosphorylation of endothelial nitric oxide synthase and Akt kinase in human umbilical vein endothelial cells were fully blocked by treatment with an endothelial nitric oxide synthase inhibitor (L-NAME), a PI3K/Akt inhibitor (LY294002), and a Ca(2+) chelator (BAPTA-AM). In parallel, the blockage of endothelial nitric oxide synthase and Akt activation subsequently fully abolished the Danggui Buxue Tang-induced nitric oxide production.

A study on the use of abbreviations among doctors and nurses in the medical department of a tertiary hospital in Malaysia.

INTRODUCTION: Misinterpretation of abbreviations by healthcare professionals has been reported to compromise patient safety. This study was done to determine the prevalence of abbreviations usage among medical doctors and nurses and their ability to interpret commonly used abbreviations in medical practice. METHODS: Seventy-seven medical doctors and eighty nurses answered a self-administered questionnaire designed to capture demographic data and information regarding abbreviation use in medical practice. Comparisons were made between doctors and nurses with regards to frequency and reasons for using abbreviations; from where abbreviations were learned; frequency of encountering abbreviations in medical practice; prevalence of medical errors due to misinterpretation of abbreviations; and their ability to correctly interpret commonly used abbreviations. RESULTS: The use of abbreviations was highly prevalent among doctors and nurses. Time saving, avoidance of writing sentences in full and convenience, were the main reasons for using abbreviations. Doctors learned abbreviations from fellow doctors while nurses learned from fellow nurses and doctors. More doctors than nurses reported encountering abbreviations. Both groups reported no difficulties in interpreting abbreviations although nurses reported often resorting to guesswork. Both groups felt abbreviations were necessary and an acceptable part of work. Doctors outperformed nurses in correctly interpreting commonly used standard and non-standard abbreviations. CONCLUSION: The use of standard and non-standard abbreviation in clinical practice by doctors and nurses was highly prevalent. Significant variability in interpretation of abbreviations exists between doctors and nurses.

Impact of assimilated and interactive aerosol on tropical cyclogenesis.

This article investigates the impact of Saharan dust on the development of tropical cyclones in the Atlantic. A global data assimilation and forecast system, the NASA GEOS-5, is used to assimilate all satellite and conventional data sets used operationally for numerical weather prediction. In addition, this new GEOS-5 version includes assimilation of aerosol optical depth from the Moderate Resolution Imaging Spectroradiometer. The analysis so obtained comprises atmospheric quantities and a realistic 3-D aerosol and cloud distribution, consistent with the meteorology and validated against Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation and CloudSat data. These improved analyses are used to initialize GEOS-5 forecasts, explicitly accounting for aerosol direct radiative effects and their impact on the atmospheric dynamics. Parallel simulations with/without aerosol radiative effects show that effects of dust on static stability increase with time, becoming highly significant after day 5 and producing an environment less favorable to tropical cyclogenesis.

CFTR suppresses tumor progression through miR-193b targeting urokinase plasminogen activator (uPA) in prostate cancer.

Cystic fibrosis (CF) transmembrane conductance regulator (CFTR) is expressed in the epithelial cells of a wide range of organs/tissues from which most cancers are derived. Although accumulating reports have indicated the association of cancer incidence with genetic variations in CFTR gene, the exact role of CFTR in cancer development and the possible underlying mechanism have not been elucidated. Here, we report that CFTR expression is significantly decreased in both prostate cancer cell lines and human prostate cancer tissue samples. Overexpression of CFTR in prostate cancer cell lines suppresses tumor progression (cell growth, adhesion and migration), whereas knockdown of CFTR leads to enhanced malignancies both in vitro and in vivo. In addition, we demonstrate that CFTR knockdown-enhanced cell proliferation, cell invasion and migration are significantly reversed by antibodies against either urokinase plasminogen activator (uPA) or uPA receptor (uPAR), which are known to be involved in various malignant traits of cancer development. More interestingly, overexpression of CFTR suppresses uPA by upregulating the recently described tumor suppressor microRNA-193b (miR-193b), and overexpression of pre-miR-193b significantly reverses CFTR knockdown-enhanced malignant phenotype and abrogates elevated uPA activity in prostate cancer cell line. Finally, we show that CFTR gene transfer results in significant tumor repression in prostate cancer xenografts in vivo. Taken together, the present study has demonstrated a previously undefined tumor-suppressing role of CFTR and its involvement in regulation of miR-193b in prostate cancer development.

Minichromosome maintenance proteins 2, 3 and 7 in medulloblastoma: overexpression and involvement in regulation of cell migration and invasion.

Minichromosome maintenance (MCM) proteins 2-7 are important in DNA replication licensing. Functional roles beyond licensing are speculated. In addition, significances in medulloblastoma (MB) remain unclear. In this study, we showed the frequent deregulation of MCM2 and MCM3 expression in 7 MB cell lines and 31 clinical samples. Moreover, DAOY and ONS76 and the clinical samples expressed elevated MCM7 transcripts with genomic gain of the gene. Immunopositivity restricted to tumor cells was found in 41, 37 and 53 out of 73 MB cases for MCM2, MCM3 and MCM7, respectively. High-MCM3 expression was associated with poor prognosis. Knockdowns of these MCMs significantly inhibited anchorage-dependent and -independent MB cell growth. The inhibition of MCM3 expression by small interfering RNA knockdown was related to G1 arrest with reduced cyclin A expression, whereas the MCM2- and MCM7-knocked-down cells arrested at G2/M with increased cyclin A expression. Interestingly, we demonstrated the links of these MCMs with cell migration and invasion using wound-healing and Transwell migration/invasion assays. Exogenous overexpression of MCM2, MCM3 and MCM7 increased anchorage-independent cell growth, and also cell migration and invasion capabilities in MB cells. The knockdown reduced the number of filopodial cells and the cells with intense stress fibers by blocking cdc42 and Rho activation. Taken together, deregulation of MCM2, MCM3 and MCM7 expression might be involved in MB tumorigenesis and we revealed undefined roles of these MCMs in control of MB cell migration and invasion.

Activation of GPR30 inhibits the growth of prostate cancer cells through sustained activation of Erk1/2, c-jun/c-fos-dependent upregulation of p21, and induction of G(2) cell-cycle arrest.

G-protein-coupled receptor-30 (GPR30) shows estrogen-binding affinity and mediates non-genomic signaling of estrogen to regulate cell growth. We here showed for the first time, in contrast to the reported promoting action of GPR30 on the growth of breast and ovarian cancer cells, that activation of GPR30 by the receptor-specific, non-estrogenic ligand G-1 inhibited the growth of androgen-dependent and androgen-independent prostate cancer (PCa) cells in vitro and PC-3 xenografts in vivo. However, G-1 elicited no growth or histological changes in the prostates of intact mice and did not inhibit growth in quiescent BPH-1, an immortalized benign prostatic epithelial cell line. Treatment of PC-3 cells with G-1 induced cell-cycle arrest at the G(2) phase and reduced the expression of G(2)-checkpoint regulators (cyclin-A2, cyclin-B1, cdc25c, and cdc2) and phosphorylation of their common transcriptional regulator NF-YA in PC-3 cells. With extensive use of siRNA-knockdown experiments and the MEK inhibitor PD98059 in this study, we dissected the mechanism underlying G-1-induced inhibition of PC-3 cell growth, which was mediated through GPR30, followed by sustained activation of Erk1/2 and a c-jun/c-fos-dependent upregulation of p21, resulting in the arrest of PC-3 growth at the G(2) phase. The discovery of this signaling pathway lays the foundation for future development of GPR30-based therapies for PCa.

A new capillary electrophoresis buffer for determining organic and inorganic anions in electroplating bath with surfactant additives.

Monitoring of trace impurities in electroplating bath is needed to meet EU requirements for WEEE and RoHS and for quality control of electrodeposits. Methods using IC and 100% aqueous CE buffer were found producing non-repeatable results attributed to interference of surfactants and major methanesulphonate anion. A new CE buffer containing 1.5mM tetraethylenepentaamine, 3mM 1,3,5-benzenetricarboxylic acid and 15 mM Tris in 20% (v/v) methanol at pH=8.4 was shown to enhance the separation window, reduce interaction between buffer and bath constituents, and give satisfactory repeatability with baseline separation for 14 organic and inorganic anions within 14 min, good repeatability for migration time (0.32-0.57% RSD), satisfactory peak area and peak height (2.9-4.5 and 3-4.7% respectively), low detection limit (S/N=2, 20-150 ppb), and wide working ranges (0.1-100 ppm). The CE buffer with 20% (v/v) methanol has demonstrated its capability for identifying anion impurities causing problem in aged tin bath and the use of only 10-fold dilution to produce reliable results for quality assessment in plating bath containing high surfactant additives.

Pharmacological investigation on the wound healing effects of Radix Rehmanniae in an animal model of diabetic foot ulcer.

ETHNOPHARMACOLOGICAL RELEVANCE: Radix Rehmanniae (RR) has a very long history of usage in traditional Chinese medicine and is usually one of the principal herb found in many herbal formulae used in diabetic foot ulcer. AIM OF THE STUDY: RR aqueous extract was investigated for its wound healing effects in a diabetic foot ulcer rat model and its detailed mechanism of actions. MATERIALS AND METHODS: A previously established diabetic foot ulcer rat model was used to assess the effect of RR extract on wound area reduction, tissue regeneration and angiogenesis. Carrageenan-induced inflammation rat model was used for inflammation study; and diabetic control was evaluated using a neonatal streptozotocin-induced diabetic rat model. RESULTS: In the RR treated group, a trend of reduction of the wound area was observed from days 8 to 18 and a significant difference (as compared with control group) was found on day 8. The ulcer healing effect of RR extract was further supported by better developed scars and epithelialization as well as good formation of capillaries with enhanced VEGF expression. Carrageenan-induced inflammation was also significantly alleviated with RR extract. CONCLUSIONS: Our results demonstrated for the first time that Radix Rehmanniae was effective in promoting diabetic foot ulcer healing in rats through the processes of tissue regeneration, angiogenesis and inflammation control, but not glycemia control. The present study provided scientific basis to support the traditional use of Radix Rehmanniae in diabetic foot ulcer.

Radix Astragali and Radix Rehmanniae, the principal components of two antidiabetic foot ulcer herbal formulae, elicit viability-promoting effects on primary fibroblasts cultured from diabetic foot ulcer tissues.

Over 194 million people suffer from diabetes worldwide. The improper control of diabetes may result in diabetic foot ulcer or even amputation. Herbal medicine provides a means for treating diabetic foot ulcers for a large population in developing countries. The wound healing-enhancing activities of the principal herbs, Radix Astragali (RA) and Radix Rehmanniae (RR) in two clinically efficacious Chinese herbal formulae were studied in primary fibroblasts from diabetic foot ulcer patients. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that RA and RR significantly enhanced the viability of fibroblasts isolated from foot ulcers of diabetic patients, even from those with no response to insulin treatment. The results in this study indicate that fibroblast viability enhancement effects of RA and RR likely underlie the healing effects of F1 and F2 in diabetic foot ulcers.

In vitro antidiabetic activities of five medicinal herbs used in Chinese medicinal formulae.

Fructus Corni, Fructus Schisandrae Chinensis, Poria, Rhizoma Alismatis and Rhizoma Dioscoreae are commonly used in traditional Chinese medicine for diabetes treatment. They are also the component herbs of an antidiabetic foot ulcer formula with demonstrated clinical efficacy. Although some of these herbal extracts were previously shown to possess in vivo antidiabetic effects (i.e. lowering blood glucose levels), the underlying mechanisms remain elusive. The objective of this study is to investigate the possible antidiabetic mechanisms of these individual herbs, using a systematic study platform which includes four in vitro tissue models: glucose absorption into intestinal brush border membrane vesicles (BBMV), gluconeogenesis by rat hepatoma cell line H4IIE, glucose uptake by human skin fibroblasts cell line Hs68 and mouse adipocytes 3T3-L1. All tested herbs showed significant in vitro antidiabetic effects in at least two models. Fructus Schisandrae Chinensis, Poria, Rhizoma Alismatis and Rhizoma Dioscoreae showed significant inhibitory effects in the BBMV glucose uptake assay. All tested herbs showed significant stimulatory effects to the glucose uptake of Hs68 and 3T3-L1 cells, except Poria and Rhizoma Dioscoreae which were not effective to Hs68 and 3T3-L1 respectively. However, none of the tested herbs inhibited hepatic gluconeogenesis. In conclusion, the five herbs exhibited distinct antidiabetic mechanisms in vitro and hence our investigations provided scientific evidence to support the traditional usage of these herbs for diabetic treatment in medicinal formulae.

Association between HLA-B*1502 allele and antiepileptic drug-induced cutaneous reactions in Han Chinese.

A previous study conducted in Taiwan found a 100% association between HLA-B*1502 allele and carbamazepine-induced Stevens-Johnson syndrome (SJS) in Han Chinese subjects, with an extremely high odds ratio compared with carbamazepine-tolerant subjects (odds ratio = 2,504). We examined this association in 24 Hong Kong Han Chinese subjects who had cutaneous adverse reactions induced by different antiepileptic drugs (AEDs). They were matched with 48 AED-tolerant controls. HLA-B*1502 was associated with severe cutaneous reactions (SCR) induced by AEDs, which included carbamazepine, phenytoin, and lamotrigine (p = 0.001, odds ratio = 17.6), but was not associated with maculopapular exanthema (MPE) (p = 0.32). Further studies in larger samples of ethnically matched subjects should be conducted to confirm the findings. Identification of genetic polymorphisms predisposing to development of AED-induced SCR offers the possibility of avoiding these high-risk drugs in genetically susceptible individuals.

Pharmacological investigations of the anti-diabetic effect of Cortex Moutan and its active component paeonol.

Cortex Moutan (CM, root bark of Paeonia suffruticosa Andr.) is one of the common herbs found in anti-diabetic traditional Chinese medicine formulae. To study the potential anti-diabetic mechanisms of CM, four in vitro models (intestinal brush border membrane vesicles (BBMV), rat hepatoma cell line H4IIE, human skin fibroblasts cell line Hs68 and mouse adipocytes 3T3-L1) were used. CM showed significant in vitro anti-diabetic effects by inhibiting glucose uptake of BBMV and enhancing glucose uptake into Hs68 and 3T3-L1 cells. Using bioassay-guided fractionation, paeonol was confirmed to be one of the active constituents for inhibiting BBMV glucose uptake. With neonatal-streptozotocin diabetic rats, paeonol (200 and 400mg/kgbody wt.) was found to improve oral glucose tolerance in vivo. To the best of our knowledge, this is the first report on the anti-diabetic effect of paeonol.

Increase in circulating Foxp3+CD4+CD25(high) regulatory T cells in nasopharyngeal carcinoma patients.

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus-associated disease with high prevalence in Southern Chinese. Using multiparametric flow cytometry, we identified significant expansions of circulating naïve and memory CD4+CD25(high) T cells in 56 NPC patients compared with healthy age- and sex-matched controls. These were regulatory T cells (Treg), as they overexpressed Foxp3 and GITR, and demonstrated enhanced suppressive activities against autologous CD4+CD25- T-cell proliferation in functional studies on five patients. Abundant intraepithelial infiltrations of Treg with very high levels of Foxp3 expression and absence of CCR7 expression were also detected in five primary tumours. Our current study is the first to demonstrate an expansion of functional Treg in the circulation of NPC patients and the presence of infiltrating Treg in the tumour microenvironment. As Treg may play an important role in suppressing antitumour immunity, our findings provide critical insights for clinical management of NPC.

Influence of an anti-diabetic foot ulcer formula and its component herbs on tissue and systemic glucose homeostasis.

Complications of diabetes impose major public health burdens worldwide. The positive effect of a Radix Astragali-based herbal preparation on healing diabetic foot ulcers in patients has been reported. Formula 1 is also referred as the 'Herbal drink to strengthen muscle and control swelling'. This formula contains six Chinese medical herbs, including Radix Astragali, Radix Rehmanniae, Rhizoma Smilacis Chinensis, Rhizoma Atractylodis Macrocephalae, Radix Polygoni Multiflori Preparata, and Radix Stephania Tetrandrae. Three of these herbs (Radix Astragali, Radix Rehmanniae, Rhizoma Atractylodis Macrocephalae) are commonly used in different anti-diabetic formulae of Chinese medicine. The objective of the current study is to use an interdisciplinary approach to test the hypothesis that Formula 1 and its components influence tissue and systemic glucose homeostasis. In vitro and in vivo models have been established including: (1) glucose absorption into intestinal brush border membrane vesicles (BBMV); (2) gluconeogenesis by H4IIE hepatoma cells; (3) glucose uptake by 3T3-L1 adipocytes and Hs68 skin fibroblasts; (4) normalization of glycaemic control in a diabetic rat model. The results of in vitro studies indicated that all herbal extracts can modify cellular glucose homeostasis. Since Formula 1 and Rhizoma Smilacis Chinensis extracts demonstrated potent effects on modifying glucose homeostasis in multiple tissues in vitro, they were further studied for their anti-diabetic activities in vivo using a streptozotocin (STZ)-induced diabetic rat model. The results showed that Formula 1 and Rhizoma Smilacis Chinensis extracts did not significantly improve oral glucose tolerance or basal glycaemia in diabetic rats. In conclusion, the anti-diabetic foot ulcer Formula 1 contains ingredients active in modifying tissue glucose homeostasis in vitro but these biological activities could not be associated with improved glycaemic control of diabetes in vivo.

Separation and determination of cations in beverage products by capillary zone electrophoresis.

Cation determination is important for quality control of beverage products. To determine a large group simultaneously, a capillary electrophoresis procedure is developed with indirect UV at 214 nm in a three-complex buffer system (10 mM N,N-dimethylbenzylamine (DBA), 8 mM lactic acid and 2 mM 18-crown-6) with good mobility matching with desired cations. Under optimized conditions with pH adjusted to 4.65, a baseline separation is achieved for 14 cations (Rb(+), NH(4)(+), K(+), Ca(2+), Na(+), Mg(2+), Mn(2+), Co(2+), Fe(2+), Cd(2+), Cr(3+), Ni(2+), Zn(2+) and Cu(2+)) within 7 min using an uncoated silica column. To cover ng/l to mug/l range, both hydrostatic and electrokinetic sampling are studied, showing working ranges within (0.05-50)/(0.005-2) microg/l and detection limits (13-78)/(1.4-10) ng/l, respectively with satisfactory repeatability (RSD 0.31-0.47% for migration time, and 3.0-4.0% for peak height measurement). Agreeable results with established inductively coupled plasma-atomic emission spectrometry method have been obtained for orange juice and tea samples.