Ruthenium(ii)-polypyridyl zirconium(iv) metal-organic frameworks as a new class of sensitized solar cells

A series of Ru(ii)L2L' (L = 2,2'-bipyridyl, L' = 2,2'-bipyridine-5,5'-dicarboxylic acid), RuDCBPY, -containing zirconium(iv) coordination polymer thin films have been prepared as sensitizing materials for solar cell applications. These metal-organic framework (MOF) sensitized solar cells, MOFSCs, each are shown to generate photocurrent in response to simulated 1 sun illumination. Emission lifetime measurements indicate the excited state quenching of RuDCBPY at the MOF-TiO2 interface is extremely efficient (>90%), presumably due to electron injection into TiO2. A mechanism is proposed in which RuDCBPY-centers photo-excited within the MOF-bulk undergo isotropic energy migration up to 25 nm from the point of origin. This work represents the first example in which a MOFSC is directly compared to the constituent dye adsorbed on TiO2 (DSC). Importantly, the MOFSCs outperformed their RuDCBPY-TiO2 DSC counterpart under the conditions used here and, thus, are solidified as promising solar cell platforms.

Serotonin Receptor 2B Mediates Mechanical Hyperalgesia by Regulating Transient Receptor Potential Vanilloid 1

Serotonin [5-hydroxytryptamine (5-HT)], an inflammatory mediator, contributes to inflammatory pain. The presence of multiple 5-HT subtype receptors on peripheral and central nociceptors complicates the role of 5-HT in pain. Previously, we found that 5-HT2B/2C antagonist could block 5-HT-induced mechanical hyperalgesia. However, the types of neurons or circuits underlying this effect remained unsolved. Here, we demonstrate that the Gq/11-phospholipase Cβ-protein kinase Cε (PKCε) pathway mediated by 5-HT2B is involved in 5-HT-induced mechanical hyperalgesia in mice. Administration of a transient receptor potential vanilloid 1 (TRPV1) antagonist inhibited the 5-HT-induced mechanical hyperalgesia. 5-HT injection enhanced 5-HT- and capsaicin-evoked calcium signals specifically in isolectin B4 (IB4)-negative neurons; signals were inhibited by a 5-HT2B/2C antagonist and PKCε blocker. Thus, 5-HT2B mediates 5-HT-induced mechanical hyperalgesia by regulating TRPV1 function.

A fixed denture for a child with epidermolysis bullosa simplex

AIM

To report the caries treatment and delivery of a fixed denture for a 3-year-old girl with epidermolysis bullosa simplex (EBS).

CASE REPORT

EBS is manifested on the skin or mucous membranes where skin separation is easily induced by trauma. Full- mouth rehabilitation under in-patient general anaesthesia was performed to the patient in conjunction with proper pre- and postoperative care. A fixed denture was fabricated and installed to replace the extracted teeth without later causing irritation on the mucosa. The prosthesis restored aesthetics and provided comfort without imposing the burden of compliance on the patient.

CONCLUSION

Aided by meticulous pre- and postoperative care and oral hygiene reinforcement, comprehensive dental treatment coupled with fixed denture delivery can greatly improve the life quality and aesthetics for children with EBS.

Male-specific association of the APC rs383830 T allele with the risk of coronary heart disease

APC is a tumor suppressor gene that is involved in the processes of cell migration and adhesion, transcriptional activation, and apoptosis. The goal of this study was to evaluate the contribution of the APC rs383830 polymorphism to coronary heart disease (CHD) in Han Chinese. A total of 783 patients with CHD and 737 controls were tested in the current association study. Although our study did not identify an association between the APC rs383830 polymorphism and CHD, a breakdown analysis by gender indicated there was a significant contribution of the rs383830 T allele to the risk of CHD in males (P = 0.046, odds ratio = 1.267, 95% confidence interval = 1.004-1.598). In conclusion, our study suggested a male-specific association of the APC rs383830 polymorphism with CHD.

Design of the radiation shielding for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

A radiation shielding has been designed to reduce scattered neutrons and background gamma-rays for the new double-ring Time Of Flight Enhanced Diagnostics (TOFED). The shielding was designed based on simulation with the Monte Carlo code MCNP5. Dedicated model of the EAST tokamak has been developed together with the emission neutron source profile and spectrum; the latter were simulated with the Nubeam and GENESIS codes. Significant reduction of background radiation at the detector can be achieved and this satisfies the requirement of TOFED. The intensities of the scattered and direct neutrons in the line of sight of the TOFED neutron spectrometer at EAST are studied for future data interpretation.

Light output function and assembly of the time-of-flight enhanced diagnostics neutron spectrometer plastic scintillators for background reduction by double kinematic selection at EAST

The 2.5 MeV neutron spectrometer TOFED (Time-Of-Flight Enhanced Diagnostics) has been constructed to perform advanced neutron emission spectroscopy diagnosis of deuterium plasmas on EAST. The instrument has a double-ring structure which, in combination with pulse shape digitization, allows for a dual kinematic selection in the time-of-flight/recoil proton energy (tof/Ep) space, thus improving the spectrometer capability to resolve fast ion signatures in the neutron spectrum, in principle up to a factor ≈100. The identification and separation of features from the energetic ions in the neutron spectrum depends on the detailed knowledge of the instrument response function, both in terms of the light output function of the scintillators and the effect of undesired multiple neutron scatterings in the instrument. This work presents the determination of the light output function of the TOFED plastic scintillator detectors and their geometrical assembly. Results from dedicated experiments with γ-ray sources and quasi-monoenergetic neutron beams are presented. Implications on the instrument capability to perform background suppression based on double kinematic selection are discussed.

Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G.

Data acquisition system with pulse height capability for the TOFED time-of-flight neutron spectrometer

A new time-of-flight neutron spectrometer TOFED has been constructed for installation at Experimental Advanced Superconducting Tokamak. A data acquisition system combining measurements of flight time and energy from the interaction of neutrons with the TOFED scintillators has been developed. The data acquisition system can provide a digitizing resolution better than 1.5% (to be compared with the >10% resolution of the recoil particle energy in the plastic scintillators) and a time resolution <1 ns. At the same time, it is compatible with high count rate event recording, which is an essential feature to investigate phenomena occurring on time scales faster than the slowing down time (≈100 ms) of the beam ions in the plasma. Implications of these results on the TOFED capability to resolve fast ion signatures in the neutron spectrum from EAST plasmas are discussed.

Monte Carlo simulation of a Bonner sphere spectrometer for application to the determination of neutron field in the Experimental Advanced Superconducting Tokamak experimental hall

To assess the neutron energy spectra and the neutron dose for different positions around the Experimental Advanced Superconducting Tokamak (EAST) device, a Bonner Sphere Spectrometer (BSS) was developed at Peking University, with totally nine polyethylene spheres and a SP9 (3)He counter. The response functions of the BSS were calculated by the Monte Carlo codes MCNP and GEANT4 with dedicated models, and good agreement was found between these two codes. A feasibility study was carried out with a simulated neutron energy spectrum around EAST, and the simulated "experimental" result of each sphere was obtained by calculating the response with MCNP, which used the simulated neutron energy spectrum as the input spectrum. With the deconvolution of the "experimental" measurement, the neutron energy spectrum was retrieved and compared with the preset one. Good consistence was found which offers confidence for the application of the BSS system for dose and spectrum measurements around a fusion device.

Postoperative adverse outcomes after non-hepatic surgery in patients with liver cirrhosis

BACKGROUND

Postoperative adverse outcomes in patients with liver cirrhosis are not completely understood. This study evaluated the association between liver cirrhosis and adverse outcomes after non-hepatic surgery.

METHODS

Reimbursement claims were used to identify patients with preoperative liver cirrhosis who underwent non-hepatic surgery from 2004 to 2007. Control patients without cirrhosis were matched by age, sex, type of surgery and anaesthesia. The adjusted odds ratios (ORs) and 95 per cent confidence intervals (c.i.) of postoperative adverse events associated with liver cirrhosis were analysed by multivariable logistic regression.

RESULTS

Thirty-day mortality rates among 24 282 patients with cirrhosis and 97 128 control patients were 1·2 per cent (299 deaths) and 0·7 per cent (635 deaths) respectively. Liver cirrhosis was associated with postoperative 30-day mortality (OR 1·88, 95 per cent c.i. 1·63 to 2·16), acute renal failure (OR 1·52, 1·34 to 1·74), septicaemia (OR 1·42, 1·33 to 1·51) and intensive care unit admission (OR 1·39, 1·33 to 1·45). Postoperative mortality increased in patients who had liver cirrhosis with viral hepatitis (OR 2·87, 1·55 to 5·30), alcohol dependence syndrome (OR 3·74, 2·64 to 5·31), jaundice (OR 5·47, 3·77 to 7·93), ascites (OR 5·85, 4·62 to 7·41), gastrointestinal haemorrhage (OR 3·01, 2·33 to 3·90) and hepatic coma (OR 5·11, 3·79 to 6·87).

CONCLUSION

Patients with liver cirrhosis had increased mortality and complications after non-hepatic surgery, particularly those with cirrhosis-related clinical indicators.

Benign myoepithelioma in the intrathoracic trachea

A 67-year-old woman who was followed as a patient with bronchial asthma for 1.5 years visited our hospital with progressive dyspnea. Although the chest radiography findings were normal, a chest computed tomography scan revealed a mass obliterating the intrathoracic tracheal lumen. The patient's symptoms disappeared immediately after tumor excision, and no recurrence was observed during a 1.5-year follow-up period. Microscopically, the tumor was composed of densely packed polygonal-, oval- and spindle-shaped cells that were positive for pan-cytokeratin, α-smooth muscle actin and p63. These pathological findings confirmed the diagnosis of benign myoepithelioma. Chest physicians should recognize that benign myoepithelioma can develop in the trachea, although it is very rare.

Prevalence of underlying lung disease in smokers with epidermal growth factor receptor-mutant lung cancer

The prevalence of underlying lung diseases, such as emphysema and interstitial lung disease in smokers with epidermal growth factor receptor (EGFR)-mutant lung cancer remains unclear. This study aimed to clarify the correlation between the EGFR mutation status and the prevalence of underlying lung disease in smokers with lung cancer. A total of 88 consecutive smokers with non-small cell or non-squamous cell lung cancer who underwent surgical resection at our hospital from January 2007 through December 2010 were included in this study. The patients were divided into two groups on the basis of the EGFR mutation status: the mutation-positive group (n=19) and the wild-type group (n=69). The results of radiographic assessment via computed tomography (CT) and pulmonary function analysis were compared between the two groups. In the radiological evaluation, CT images at three levels were evaluated by two reviewers. Radiographic assessment revealed that the mutation-positive group tended to have milder emphysematous changes and a lower prevalence of interstitial changes compared with the wild-type group (P=0.13, 0.06). When the analysis was limited to the ipsilateral lung at the nearest CT level to the tumor, emphysematous changes were found to be less common in the mutation-positive group (P=0.02). The prevalence of the emphysematous and/or interstitial changes in the ipsilateral lung at the nearest CT level to the tumor was lower in the mutation-positive group compared to the wild-type group (P=0.005). In the pulmonary function test, the results were comparable between the two groups. In conclusion, according to our results, EGFR-mutant lung cancer was commonly observed in the areas where emphysematous and interstitial changes were absent. EGFR-mutant lung cancer may develop in radiographically normal areas of the lungs, even in smokers. It would be of importance to evaluate the EGFR mutation status in patients with no emphysematous or interstitial changes in the ipsilateral lung near the tumor, regardless of their smoking history. These results should be confirmed in a future prospective study.

The resistive bolometer for radiated power measurement on EAST

The resistive bolometer system has been successfully employed on experimental advanced superconducting tokamak for the first time to measure the radiated power of plasma. The bolometer detectors are based on 4 μm thick Pt absorbers deposited on 1.5 μm thick SiN membranes. The system consists of 3 cameras with a total of 48 channels. The detector and the system setup are described in detail. The detector calibration and typical measurement results are presented as well.

Two cases of tuberculosis with multiple drug hypersensitivity after drug-induced hypersensitivity syndrome

Here, we report 2 cases of drug-induced hypersensitivity syndrome (DIHS) caused by salazosulfapyridine and allopurinol during tuberculosis treatment. Both patients also developed multiple drug hypersensitivity (MDH) to several antituberculosis drugs that were used at around the period of DIHS onset, and thus, the treatment could not be successfully completed. Our cases show that MDH can easily occur after development of DIHS. Considering that treatment for tuberculosis requires long-term management with several drugs, it is important to refrain from administering drugs that can cause DIHS during tuberculosis treatment.

Prospective evaluation of seropositive occult hepatitis B viral infection in lymphoma patients receiving chemotherapy

OBJECTIVE. To serially evaluate the viral kinetics of occult hepatitis B virus infection in lymphoma patients and perform a correlation with clinical outcomes. DESIGN. Case series with 1-year follow-up. SETTING. Regional hospital, Hong Kong. PATIENTS. Consecutive patients who were newly diagnosed to have lymphoma in the hospital between 1 April 2007 and 31 March 2008 were tested for hepatitis B (HB) surface (s) antigen (Ag), anti-HBs antibody (Ab) and anti-HB core (c) Ab. Seropositive occult hepatitis B patients as defined by being negative for HBsAg but positive anti-HBsAb and/or anti-HBcAb without a hepatitis B vaccination history were recruited. Serum HBsAg, anti-HBsAb, anti-HBcAb, hepatitis B virus deoxyribonucleic acid (DNA) level, and liver biochemistry were checked at baseline and every 4 weeks during and after chemotherapy until 12 months after the completion of chemotherapy or death. Entecavir was started if patients developed biochemical flare-up of hepatitis B associated with virological rebound. The prevalence and course of hepatitis B virus-related hepatitis, as well as any temporal relationship to viral kinetics and clinical hepatitis, were assessed. RESULTS. Of 47 patients tested, 10 (21%) with lymphoma were seropositive occult hepatitis carriers. Their median baseline hepatitis B virus DNA level was 89 IU/mL (range, <34-807 IU/mL). Virological rebound (as defined by a 10-fold increase in serum hepatitis B virus DNA level from pre-chemotherapy level persisted for 4 weeks) occurred in one of the 10 patients, followed by biochemical reactivation. Whereupon entecavir treatment was started and no liver failure ensued. Regarding the other seropositive occult patients, their serum hepatitis B virus DNA levels fluctuated, but there was no associated biochemical reactivation. CONCLUSION. Detectable baseline serum hepatitis B virus DNA is not uncommon in patients with occult hepatitis B who receive chemotherapy. Transient elevation in serum hepatitis B virus DNA levels does not predict biochemical reactivation, but antiviral treatment might be considered if virological rebound persists.

A synopsis of current care of thalassaemia major patients in Hong Kong

OBJECTIVE

To provide a synopsis of current thalassaemia major patient care in Hong Kong.

DESIGN

Retrospective study.

SETTING

All haematology units of the Hospital Authority in Hong Kong.

PATIENTS

All patients with thalassaemia major with regular transfusion.

RESULTS

To date, there were 363 thalassaemia major patients under the care of the Hospital Authority. Prenatal diagnosis has helped to reduce the number of indigenous new cases, but in recent years immigrant cases are appearing. The patients have a mean age of 23 (range, 1-52) years, and 78% of them are adults. In 2009, they received 18 782 units of blood. This accounted for 9.5% of all blood consumption from the Hong Kong Red Cross. In the past, cardiac iron overload was the major cause of death (65%) and few patients survived beyond the age of 45 years. The availability of cardiac iron assessment by magnetic resonance imaging (T2 MRI) to direct the use of oral deferiprone chelation has reduced the prevalence of heart failure and cardiac haemosiderosis, which should reduce mortality and improve life expectancy.

CONCLUSION

The future for thalassaemia care in Hong Kong is bright. With better transfusion and chelation, it should be possible to avoid growth and endocrine deficiencies in younger patients.

A synopsis of current haemophilia care in Hong Kong

OBJECTIVE

To provide a synopsis of current haemophilia care in Hong Kong.

DESIGN

Retrospective survey.

SETTING

All haematology units of the Hospital Authority in Hong Kong.

PATIENTS

All patients with haemophilia A and haemophilia B.

RESULTS

To date, there were 222 mild-to-severe haemophilia patients (192 type A, 30 type B) under regular public care in Hong Kong (43% were considered severe, 33% moderate, and 24% mild), which gave a crude prevalence of 6.8/100 000 male inhabitants. A total of 12.8 million units of Factor VIII and 3 million units of Factor IX were prescribed annually. This amounts to 1.83 units of FVIII per capita of the population, which is comparable to that of other developed countries. Leading causes of mortality were human immunodeficiency virus-related complications (10 cases) and cerebral bleeding (2 cases). The life expectancy of patients with severe haemophilia in Hong Kong is improving; currently the oldest patient is 60 years old. Such improved survival may be due to enhanced factor availability, prompt treatment of bleeding episodes at home, safer factor products, and better antiviral treatment. Primary prophylaxis is the accepted standard of care for severe and moderate cases, and "Factor First" has become hospital policy. However, 12 patients continue to present treatment challenges, due to the documented presence of factor inhibitors. In all, 28, 100, and 14 cases respectively were positive for human immunodeficiency virus, hepatitis C virus, and hepatitis B virus; the youngest patients with the corresponding infections being 28, 13, and 22 years old. Comprehensive care with dedicated physiotherapy, surgical support, and radionucleotide synovectomy may reduce morbidity further.

CONCLUSION

A multidisciplinary approach can further improve the future care for haemophilia patients in Hong Kong.

First results obtained from the soft x-ray pulse height analyzer on experimental advanced superconducting tokamak

An assembly of soft x-ray pulse height analyzer system, based on silicon drift detector (SDD), has been successfully established on the experimental advanced superconducting tokamak (EAST) to measure the spectrum of soft x-ray emission (E=1-20 keV). The system, including one 15-channel SDD linear array, is installed on EAST horizontal port C. The time-resolved radial profiles of electron temperature and K(alpha) intensities of metallic impurities have been obtained with a spatial resolution of around 7 cm during a single discharge. It was found that the electron temperatures derived from the system are in good agreement with the values from Thomson scattering measurements. The system can also be applied to the measurement of the long pulse discharge for EAST. The diagnostic system is introduced and some typical experimental results obtained from the system are also presented.

O+OH-->O(2)+H: A key reaction for interstellar chemistry. New theoretical results and comparison with experiment

We report extensive, fully quantum, time-independent (TID) calculations of cross sections at low collision energies and rate constants at low temperatures for the O+OH reaction, of key importance in the production of molecular oxygen in cold, dark, interstellar clouds and in the chemistry of the Earth's atmosphere. Our calculations are compared with TID calculations within the J-shifting approximation, with wave-packet calculations, and with quasiclassical trajectory calculations. The fully quantum TID calculations yield rate constants higher than those from the more approximate methods and are qualitatively consistent with a low-temperature extrapolation of earlier experimental values but not with the most recent experiments at the lowest temperatures.

Japanese lung cancer research trends and performance in Science Citation Index

OBJECTIVE

This study was undertaken to explore a bibliometric approach to quantitatively assess current research trends in lung cancer in Japan, using the related literature in the Science Citation Index (SCI) database from 1991 to 2008.

MATERIALS AND METHODS

Articles were analyzed by the scientific output and research performances of individuals, institutes, and collaborative countries with Japan. Distribution of words in the article title, author keywords, and KeyWords Plus in different periods was applied to evaluate research trends by the frequency of keywords used.

RESULTS

Keyword analysis indicated that there has been a strategy to connect molecular biology with clinical practice. Researchers in Japan have published high impact articles related to non-small cell and small cell lung cancer.

CONCLUSION

Finally, this study highlights the topics in lung cancer research that are becoming popular in Japan.