A Study of Piezoelectric Field Related Strain Difference in GaN-Based Blue Light-Emitting Diodes Grown on Silicon(111) and Sapphire Substrates.

We investigate the strain difference in InGaN/GaN multiple quantum wells of blue light-emitting diode (LED) structures grown on silicon(1 11) and c-plane sapphire substrates by comparing the strength of piezo-electric fields in MQWs. The piezo-electric fields for two LED samples grown on silicon and sapphire substrates are measured by using the reverse-bias electro-reflectance (ER) spectroscopy. The flat-band voltage is obtained by measuring the applied reverse bias voltage that induces a phase inversion in the ER spectra, which is used to calculate the strength of piezo-electric fields. The piezo-electric field is determined to be 1.36 MV/cm for the LED on silicon substrate and 1.83 MV/cm for the LED on sapphire substrate. The ER measurement results indicate that the strain-induced piezo-electric field is greatly reduced in the LED grown on silicon substrates consistent with previous strain measurement results by micro-Raman spectroscopy and high-resolution transmission electron microscopy.

Persistence of solifenacin therapy in patients with overactive bladder in the clinical setting: a prospective, multicenter, observational study.

OBJECTIVES: The aim of this study was to evaluate the persistence with solifenacin therapy over a 12-month period in patients with overactive bladder (OAB). METHODS: This is a 52-week long, multicenter, prospective, observational study. The subjects were individuals ≥ 18 years old with OAB symptoms for ≥ 3 months, characterised by a total OAB Symptom Score (OABSS) of ≥ 3 and OABSS urgency item score of ≥ 2. Patients were prescribed 5 mg or 10 mg of solifenacin once daily for OAB symptoms. Drug persistence, reasons for discontinuation and factors related to the persistence were evaluated. RESULTS: A total of 1018 patients (329 men, 689 women) with a mean age of 59 years were included. The 52-week drug persistence rate was 22.1%. The drug persistence rates at 12, 24 and 36 weeks were 72.4%, 45.8% and 31.1% respectively. The three most common reasons for discontinuing therapy included symptom improvement in 30.4%, lack of efficacy in 13.4%, and a switch to another antimuscarinic agent in 10.8%. Older patients (odds ratio = 1.02, 95% CI: 1.01-1.04), and female patients (odds ratio = 1.94, 95% CI: 1.37-2.75) were more likely to continue the medication over the 12-month period than were younger, male patients. The number of nocturia episodes was negatively correlated with drug persistence (odds ratio = 0.83, 95% CI: 0.71-0.97). CONCLUSIONS: There was low persistence (22%) to solifenacin therapy for OAB symptoms over a 12-month period. Older patients, female patients and those with fewer episodes of nocturia were more persistent to therapy than were others.

Comparison of Strain in GaN-Based Blue Light-Emitting Diode Grown on Silicon(111) and Sapphire Substrates.

We compare the strain states and device performances of GaN-based blue light-emitting diodes (LEDs) grown on Si(111) and sapphire substrates. The strain characteristics are investigated using micro-Raman spectroscopy and high-resolution transmission electron microscopy. These analyses reveal that GaN layer grown on Si has a residual tensile strain in contrast to a compressive strain for GaN on sapphire, and quantum wells (QWs) on GaN/Si experience reduced lattice mismatch than those of GaN/sapphire. When external quantum efficiencies of LED on sapphire and Si substrates are compared, the LED on Si shows better efficiency droop characteristics and this is attributed to a decrease in piezo-electric field strength in InGaN/GaN layers owing to reduced lattice mismatch.

Phosphorus adsorption characteristics of oyster shells and alum sludge and their application for nutrient control in constructed wetland system.

This research aimed to evaluate the feasibility of employing some locally available oyster shells (OS) and alum sludge (AS) as the P adsorption media of constructed wetland beds. The batch and column tests were conducted with different sizes of OS and AS to observe the P adsorption characteristics and breakthrough, while P adsorption rates were determined from jar test. From the batch test, the ability to adsorb the amount of added P was different considerably between OS and AS media and sizes. At the same size, the P adsorption capacities of OS were higher than those of alum sludge. The P adsorption capacities of AS with 0.3-0.6 mm and > 0.6 mm sizes were similar, but those of 0.3-0.6 mm OS was higher than > 0.6 mm OS. Jar test results revealed the first-order P removal rates (k) to be 11.4, 4.5, 1.7 and 1.0 d(- 1) for the 0.3-0.6 mm AS, > 0.6 mm AS, 0.3-0.6 mm OS, and > 0.6 mm OS, respectively. From the column tests, the adsorption capacities were found to be more than 26 and 24.5 g/kg for the OS media sizes of 0.3-0.6 and > 0.6 mm, respectively, and 12 g/kg for the AS media. The column tests revealed that AS was able to adsorb P faster than the oyster shells, but due to its low adsorption capacity, the periods of P breakthrough in the effluent of the alum sludge columns were shorter than those of the oyster shell columns. Experiments with a pilot-scale vertical-flow subsurface constructed wetland unit packed with > 0.6 mm OS media demonstrated the high P removal efficiencies of more than 96.2% during the 210 days of operation.

Influence of bladder management on epididymo-orchitis in patients with spinal cord injury: clean intermittent catheterization is a risk factor for epididymo-orchitis.

STUDY DESIGN: Retrospective study, based on cases of spinal cord injury (SCI). OBJECTIVES: To establish hazard ratios for risk of epididymo-orchitis in SCI. SETTING: South Korea. METHODS: A total of 140 male patients injured before 1987 were eligible for this investigation and have been followed up on a yearly basis from January 1987 to December 2003. RESULTS: The average age at which the lesion occurred was 24.8 years old (range, 18-53). The average time since SCI was 16.9 years (range, 1-37). A total of 34 lesions (24.3%) were complete and 106 (75.7%) were incomplete. Over the 17 years, 39 patients (27.9%) were diagnosed with epididymo-orchitis. Epididymo-orchitis was more common for patients with a history of urethral stricture (66.7 versus 25.2%, P=0.014). We also found that epididymo-orchitis was more common for patients on clean intermittent catheterization (CIC) than with indwelling urethral catheterization (42.2% versus 8.3%, P=0.030). In multivariate analysis, patients on CIC had a 7.0-fold higher risk (odds ratio, 6.96; 95% confidence interval, 1.26-38.53; P=0.026); however, a history of urethral stricture lost statistical significance (P=0.074). For other variables, no positive association with epididymo-orchitis was observed. CONCLUSIONS: In this study, CIC was an independent risk factor for the development of epididymo-orchitis in patients with SCI. In addition, our findings suggest that urethral stricture may be a contributing factor for the development of epididymo-orchitis in these patients. Correct instructions about CIC are of utmost importance.

Technical innovation for noninvasive and early diagnosis of biliary atresia: the ultrasonographic "triangular cord" sign.

In this article, we introduce our experience regarding a new and noninvasive diagnostic tool, using ultrasonography, for the early and definite diagnosis of biliary atresia. We have focussed on the ultrasonographic image of the cone-shaped periportal fibrous mass in infants with biliary atresia since 1992, and have finally identified a triangular or band-like periportal echogenicity ("triangular cord" sign), mainly cranial to the portal vein. Based on our experience and other reports from Japan and Singapore, the ultrasonographic triangular cord sign is a simple, time-saving, highly reliable, and definite tool in the diagnosis of biliary atresia from infantile intrahepatic cholestasis, representing a positive predictive value greater than 95%. We have proposed a new diagnostic strategy in the evaluation of infantile cholestasis, with emphasis on the ultrasonographic triangular cord sign.

Phenol block of peripheral nerve conduction: Titrating for optimum effect.

OBJECTIVES: To verify the dose-response relationship in phenol nerve block and to determine the concentration and volume of phenol injectate required for effective nerve conduction block. DESIGN: Before-after, experimental study. SETTING: A research institute laboratory. ANIMALS: Seventy-one New Zealand white rabbits. INTERVENTIONS: Group I (n = 48) received tibial nerve block by perineural injection (phenol, n = 40; saline, n = 8), group II (n = 21) by submerging the nerve in phenol solution. The 6 subgroups of group I each received different concentrations (3%, 4%, 5%) and volumes (0.1mL, 0.2mL, 0.3mL). The 2 subgroups of group II received 3% (n = 8) and 5% (n = 13) phenol. MAIN OUTCOME MEASURES: Compound muscle action potential (CMAP) and tension of triceps surae muscles by electric stimulation of the sciatic nerve were measured preintervention and at day 1, and weeks 1, 2, 4, and 8 postblock. Histologic studies were performed on 2 animals from group I. RESULTS: Two rabbits in group I died before results were obtained. In the remaining animals, CMAP amplitude reduced significantly (p <.05) as the volume of 5% phenol solution increased from 0.1mL, 0.2mL, to 0.3mL. A high concentration of phenol produced a more pronounced conduction block; however, no significant (p =.0589) difference existed among the 3 concentrations. Submerged tibial nerve had a greater degree of conduction block than perineurally injected nerve. Depth of the degeneration area in nerve fascicle varied with distance from the injection point. CONCLUSIONS: The nerve block effect of phenol can be titrated by adjusting the concentration and volume of phenol solution if the technique of application and localization of a block site are standardized.

Cystic rectal duplication: a rare cause of neonatal bladder-outlet obstruction and hydronephrosis.

A case of cystic rectal duplication (RD) is presented. A 7-day-old female was admitted with acute urinary retention, voiding difficulty, and abdominal distention since she was 4 days of age. Ultrasound and abdominal computed tomography (CT) demonstrated a huge, cystic mass in the pelvis and abdomen that resulted in acute urinary retention and bilateral hydronephrosis. CT-guided drainage of the lesion followed by transabdominal surgical excision resulted in a cure. Pathologic examination demonstrated a RD lined by respiratory epithelium.

Potential role of caspase-3 and -9 in arsenic trioxide-mediated apoptosis in PCI-1 head and neck cancer cells.

Arsenic trioxide (As2O3) has been shown to inhibit the proliferation of hematologic malignant cells. Previously, we reported that As2O3 had an antitumoral effect in head and neck cancer. Here, we investigated the induction of apoptosis and its mechanism in PCI-1 head and neck squamous carcinoma cells, after treatment with As2O3. Treatment with 2 microM of As2O3 caused apoptosis in PCI-1 cells following 3 days of exposure, which was detected by the annexin V-PI and DAPI staining methods. The cell death population was markedly increased, being 88% larger than the As2O3-untreated control cells. To address the mechanism of apoptosis, a Western blot assay was performed, showing that Bax was up-regulated without a change in Bcl-2. Activation of caspase-9 during As2O3-induced apoptosis was substantiated by monitoring the proteolysis of the caspase-9, which was associated with an increase of Apaf-1 and cytochrome c protein. PCI-1 cells rapidly changed the mitochondria membrane potential (DeltaPsim) after addition of As2O3. Furthermore, activation of caspase-3 was demonstrated by monitoring the proteolysis of the caspase-3 and by measuring caspase-3 activity with a fluorogenic substrate, which was associated with the cleavage of poly(ADP-ribose) polymerase. To examine the in vivo effect of As2O3, C3H mouse inoculated with syngenic SCC7 cells was treated by intratumoral injection of As2O3 (300 microg) every day, demonstrating that tumor mass was dramatically reduced on day 4, and revealed induction of apoptosis by TUNEL assay. These results suggest that apoptosis of PCI-1 cells by As2O3 is induced by activation of caspase-3 via cytochrome c, caspase-9 and Apaf-1 complex.

Generalized eruptive histiocytoma: a pediatric case.

Generalized eruptive histiocytoma (GEH) is a rare, benign, papular, self-healing histiocytosis characterized by recurrent crops of small, firm, tan to reddish papules that appear in a symmetrical fashion on the face, trunk and arms, affecting mainly adults. Approximately 31 cases have been described, of which 8 were in children. A new concept unifying the confusing potpourri of non-Langerhans cell histiocytosis has recently been described in which GEH has been considered to represent an early undifferentiated stage of various histiocytic disorders. We describe a 9-year-old boy who had all the features of GEH and emphasize the importance of clinical, histologic, immunohistochemical, and ultrastructural examination in the diagnosis of histiocytic disorders. On the basis of the increasing numbers of similar reported cases showing overlap in clinical and histologic features and in accordance with the new unifying concept of non-Langerhans cell histiocytosis, we presume that this group of disorders may represent a continuous spectrum of a single disease rather than a collection of separate disorders.

A case of primary cutaneous actinomycosis.

Primary cutaneous actinomycosis is very uncommon because of the exclusively endogenous habitat of the organism. We report a case of primary cutaneous actinomycosis characterized by histopathological "sulfur granules". The patient had a well-defined subcutaneous nodule on the left thigh without any other lesion and was treated with surgical excision and subsequent oral ampicillin for six weeks. There has been no recurrence during a 1-year period of follow-up.

A case of cutaneous reaction to chemotherapeutic agents showing epidermal dysmaturation.

Cutaneous chemotherapy reactions are more likely to be toxic than allergic. Epidermal dysmaturation refers to histologic changes that may be observed in the epidermis after any significant cytoreductive therapy. We report a case of epidermal dysmaturation occurring in a patient with acute myelogenous leukemia after antineoplastic chemotherapy.

Induction of apoptosis by vitamin D3 analogue EB1089 in NCI-H929 myeloma cells via activation of caspase 3 and p38 MAP kinase.

EB1089, a novel 1,25-dihydroxyvitamin D3 analogue, has been known to have potent antiproliferative properties in a variety of malignant cells both in vitro and in vivo. In the present study, we analysed the effect of EB1089 on NCI-H929 human myeloma cells. EB1089 inhibited cell growth of NCI-H929 and efficiently induced the G1 phase arrest of the cell cycle in a dose-dependent manner. We could also detect apoptosis in NCI-H929 cells exposed to EB1089 (1 x 10-7 M for 72 h) using the sub-G1 group of the cell cycle by FACS and annexin V binding assays. Induction of apoptosis by EB1089 was associated with down-regulation of the Bcl-2 protein without change of the Bax protein. Regarding caspase activity, which plays a crucial role in apoptosis, EB1089-treated NCI-H929 cells revealed an increased activity of caspase 3 protease accompanied by degradation of the PARP protein in a dose- and time-dependent manner. In addition, EB1089 caused the down-regulation of p44 extracellular signal-related kinase (ERK) activity and up-regulation of the p38 kinase activity during apoptosis of NCI-H929 cells. These results suggest that EB1089 inhibits growth of NCI-H929 cells via G1 cell cycle arrest as well as apoptosis by activating p38 kinase and suppressing ERK activity.

Arsenic trioxide-mediated growth inhibition in MC/CAR myeloma cells via cell cycle arrest in association with induction of cyclin-dependent kinase inhibitor, p21, and apoptosis.

We investigated the in vitro effect of As2O3 on proliferation, cell cycle regulation, and apoptosis in human myeloma cell lines. As2O3 significantly inhibited the proliferation of all of eight myeloma cell lines examined in a dose-dependent manner with IC50 of approximately 1-2 microM. DNA flow cytometric analysis indicated that As2O3 (2 microM) induced a G1 and/or a G2-M phase arrest in these cell lines. To address the mechanism of the antiproliferative effect of As2O3, we examined the effect of As2O3 on cell cycle-related proteins in MC/CAR cells in which both G1 and G2-M phases were arrested. Western blot analysis demonstrated that treatment with As2O3 (2 microM) for 72 h did not change the steady-state levels of CDK2, CDK4, cyclin D1, cyclin E, and cyclin B1 but decreased the levels of CDK6, cdc2, and cyclin A. The mRNA and protein levels of CDKI, p21 were increased by treatment with As2O3, but those of p27 were not. In addition, As2O3 markedly enhanced the binding of p21 with CDK6, cdc2, cyclin E, and cyclin A compared with untreated control cells. Furthermore, the activity of CDK6-associated kinase was reduced in association with hypophosphorylation of Rb protein. The activity of cdc2-associated kinase was decreased, which was accompanied by the up-regulation of cdc2 phosphorylation (cdc2-Tyr15 phosphorylation) resulting from reduction of cdc25B and cdc25C phosphatases. As2O3 also induced apoptosis in MC/CAR cells as evidenced by flow cytometric detection of sub-G1 DNA content and annexin V binding assay. This apoptotic process was associated with down-regulation of Bcl-2, loss of mitochondrial transmembrane potential (delta psi(m)), and an increase of caspase-3 activity. These results suggest that As2O3 inhibits the proliferation of myeloma cells, especially MC/CAR cells, via cell cycle arrest in association with induction of p21 and apoptosis.

Solitary sclerotic fibroma of the skin: degenerated sclerotic change of inflammatory conditions, especially folliculitis.

Two cases showing changes of sclerotic fibroma developed in association with an inflammatory process, especially folliculitis. The lesion in the first case showed a well-circumscribed, nonencapsulated nodule in the dermis, which consisted of a perifollicular fibrotic area and a peripheral sclerotic area. In addition to the usual findings of sclerotic fibroma, spindle cells were heavily infiltrated in a storiform and fascicular pattern around the degenerated hair follicle, suggestive of dermatofibroma. The lesion in the second case showed the typical findings of sclerotic fibroma in association with folliculitis and hair follicle remnants. Our observations suggest that solitary sclerotic fibroma of the skin may be a degenerated or sclerotic end stage of other fibrous conditions, such as dermatofibroma, and that it may be induced by inflammation, especially folliculitis.

A case of linear scleroderma and myasthenia gravis.

We report a case of a 28-year-old woman with myasthenia gravis who developed linear scleroderma seven years later. Myasthenia gravis and scleroderma are rarely found in direct association with each other; there are only five such reported cases, all of which were systemic scleroderma patients. Although localized and systemic scleroderma are distinct entities, autoimmunity is believed to be involved in the pathogenesis of both. Myasthenia gravis and scleroderma may occur coincidentally, but an autoimmune predisposition seems to be the more likely underlying cause, as evidenced by an increased incidence of autoantibodies and autoimmune diseases.