Removal of phosphate from water by a highly selective La(III)-chelex resin

A new polymer ligand exchanger (PLE) has been developed for the removal of phosphate in wastewater. This PLE, consisting of lanthanum(III) bound to chelex-100 resin, was prepared by passing LaCl3 solution through a column of chelex-100. Uptake of phosphate from water by this La-chelex resin was investigated in the column mode. The La-chelex resin was able to remove phosphate efficiently from water, and the uptake of phosphate was not affected by the presence of large amounts of anions (0.1M) such as chloride and sulfate. The La-chelex resin was also able to efficiently remove phosphate from seawater to <0.1mg-Pl(-1), and regenerated for reuse by removing the sorbed phosphate by eluting with 6M HCl.

Passive smoking exposure and risk of COPD among adults in China: the Guangzhou Biobank Cohort Study

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality in China, where the population is also exposed to high levels of passive smoking, yet little information exists on the effects of such exposure on COPD. We examined the relation between passive smoking and COPD and respiratory symptoms in an adult Chinese population.

METHODS

We used baseline data from the Guangzhou Biobank Cohort Study. Of 20 430 men and women over the age of 50 recruited in 2003-06, 15,379 never smokers (6497 with valid spirometry) were included in this cross-sectional analysis. We measured passive smoking exposure at home and work by two self-reported measures (density and duration of exposure). Diagnosis of COPD was based on spirometry and defined according to the GOLD guidelines.

FINDINGS

There was an association between risk of COPD and self-reported exposure to passive smoking at home and work (adjusted odds ratio 1.48, 95% CI 1.18-1.85 for high level exposure; equivalent to 40 h a week for more than 5 years). There were significant associations between reported respiratory symptoms and increasing passive smoking exposure (1.16, 1.07-1.25 for any symptom).

INTERPRETATION

Exposure to passive smoking is associated with an increased prevalence of COPD and respiratory symptoms. If this association is causal, we estimate that 1.9 million excess deaths from COPD among never smokers could be attributable to passive smoking in the current population in China. Our findings provide strong evidence for urgent measures against passive smoking in China.

Treatment outcomes in anaplastic thyroid carcinoma from 1966–2006: Failure of overall survival enhancement despite four decades of progress in surgery, radiotherapy and chemoradiation

16537

Introduction: Anaplastic thyroid carcinoma (ATC) is a notoriously aggressive malignancy associated with a highly lethal clinical course despite therapeutic intervention. To identify factors that could suggest improved therapeutic strategies, we have analysed the clinicopathological features, treatment and outcome of all patients with ATC treated over the past four decades in our institution. Methods: Fifty patients presenting with biopsy-proven ATC to our centre between 1966 and 2006 were studied. All patients were managed with surgery, radiotherapy, chemotherapy, and/or chemoradiation. Survival was calculated using the Kaplan-Meier method. Potential factors affecting survival were compared using the log-rank test. Results: Most patients (88%) presented with a neck mass, while 17 (34%) patients also had cervical lymphadenopathy. Distant metastases at diagnosis were present in 9 (18%) of patients. Median survival was 97 days, while the 1- and 3-year survival was 14 % and 8% respectively. On univariate analysis, patients aged ≤65 years (p=0.04), undergoing surgical resection (p<0.01), receiving RT to the neck (p<0.01) and without metastatic disease on presentation (p<0.01) enjoyed longer survival. Cytotoxic chemotherapy was not associated with survival enhancement (p = 0.4). Moreover, no change in survival was evident as a function of treatment era (p = 0.5). Conclusions: ATC remains a uniformly lethal disease despite numerous technical advances in surgery, radiotherapy and chemotherapy over the last forty years. Nonetheless, our results indicate that younger patients with localized ATC be treated aggressively in a multimodality manner. Identification of signalling pathways that can be medically blocked to reduce ATC metastatic/invasive potential and enhance apoptotic sensitivity should now be the main priority for multicentre collaborative clinical research.

No significant financial relationships to disclose.

Descriptive analysis of retirement of Thoroughbred racehorses due to tendon injuries at the Hong Kong Jockey Club (1992-2004)

REASONS FOR PERFORMING STUDY

This study was part of a programme to optimise the longevity and maximise the health and welfare of the Thoroughbred racehorses in Hong Kong. Injuries to the superficial digital flexor (SDF) tendon are the most common veterinary reason for premature retirement in this population.

OBJECTIVE

To describe the frequency and pattern of retirements associated with SDF tendon injuries in Thoroughbred racehorses and to compare the characteristics of these horses with those that retired for other reasons.

METHODS

A retrospective analysis of retirement records documented in the Hong Kong Jockey Club clinical database between 1992 and 2004 was conducted. As this is complete census data, no statistical inference to the population is necessary.

RESULTS

The mean annual cumulative incidence of retirements due to tendon injury was 3.2% accounting for 14% of all retirements. The risk of tendon injury increased over the 12 year period from 23-4.2%. The racing career, number of starts and earnings of horses retired with tendon injuries were reduced by 25.6, 41.2 and 53.3%, respectively. Thirteen percent of these horses never raced in Hong Kong. A greater proportion of 3- and 4-year-olds and entire males were retired because of tendon injuries. Ninety-seven percent of injuries affected the forelimb, the right more frequently than the left. Only 19.7% of retired horses that had received ultrasound examination for SDF tendon injury retired for this reason.

CONCLUSIONS

This study provides population based data on the frequency, career and economic losses associated with tendon injury induced retirement.

POTENTIAL RELEVANCE

This descriptive study has provided a useful resource for further case-control studies to investigate risk factors for retirement from racing due to tendon injury. This is the first step toward the development of management tools to reduce the incidence of tendon injury related retirement in Hong Kong.

Prospective comparison of clinical and computed tomography assessment in detecting uterine perforation with intracavitary brachytherapy for carcinoma of the cervix

Brachytherapy (BT) is an essential component of radical treatment for cervix cancer. Uterine perforation is a potential complication of intrauterine applicator (tandem) insertion. Postprocedure pelvic computed tomography (CT) scans are routinely performed at this center. The objective of this study was to prospectively compare radiation oncologists' (RO) clinical impression of satisfactory tandem placement with actual tandem placement as determined from pelvic CT. Patients with cervix cancer undergoing low-dose rate BT from April 2003 to December 2005 were prospectively identified. After tandem placement, patients were brought to the radiotherapy department for pelvic imaging (plain films and CT). Prior to viewing imaging, the RO specified whether they were concerned vs not concerned about uterine perforation. The CT was then reviewed to determine actual tandem placement (perforation vs no perforation). One hundred twenty-four sequential tandem insertions were performed in 114 patients and eligible for analysis. The incidence of CT detected uterine perforation was 13.7% (17/124). Physician concern, age greater than or equal to 60, and tumor size were significant predictors of uterine perforation (P < 0.0001, P= 0.0019, and P= 0.0016, respectively). The overall sensitivity and specificity for physician concern was 52.9% and 84.1%, respectively. CT detected perforation in 8.2% (8/98) of insertions where the RO was clinically confident of correct tandem placement. Pelvic CT was a useful modality to accompany clinical assessment in identifying uterine perforation in cervix BT. As a low but potentially clinical significant number of perforations identified on CT were not suspected clinically, we recommend acquiring pelvic imaging in all patients following tandem insertion to ensure intrauterine tandem positioning.

A lead-free piezoelectric transformer in radial vibration modes

In this study, a disk-shaped piezoelectric transformer was fabricated using lead-free (K,Na)NbO(3)-based ceramics with high mechanical quality factor. The transformer can operate in the fundamental or the third radial vibration mode. The transformer is poled along the thickness direction. The top surface is covered by ring/dot silver electrodes separated by an annular gap which serve as the input and output parts of the transformer, respectively. The bottom surface, fully covered with a silver electrode, is grounded as a common electrode. The dimensions of the top ring/dot electrodes are designed such that the third radial vibration mode can be strongly excited. The electrical properties of the transformer with diameter of 34.2 mm and thickness of 1.9 mm were measured. For a temperature rise of 35 degrees C, the transformer has a maximum output power of 12 W. With the matching load, its maximum efficiency is >95%, and maximum voltage gains are 6.5 and 3.9 for the fundamental and the third radial vibration modes, respectively. It has potential to be used in power supply units and other electronic circuits.

TuBaFrost: European virtual tumor tissue banking

TuBaFrost is a consortium responsible for the task to create a virtual European human frozen tumor tissue bank, composed of high quality frozen tumor tissue collections with corresponding accurate diagnosis stored in European cancer centers and universities, searchable on the Internet, providing rules for access and use and a code of conduct to comply with the various legal and ethical regulations in European countries. Such infrastructure would enlarge tissue availability and accessibility in large amounts of specified or even rare tumor samples. Design of an infrastructure for European residual tissue banking with the described characteristics, clear focus points emerge that can be broken down in dedicated subjects: (1) standardization and quality assurance (QA) to avoid inter-institute quality variation; (2) law and ethics enabling exchange of tissue samples possible between institutes in the different European countries, where law and ethics are characterized by a strong variability; (3) rules for access, with sufficient incentives for collectors; (4) central database application containing innovations on search and selection procedures; (5) support when needed with histology images; and (6) Internet access to search and upload, with in addition a solid website giving proper information on the procedures, intentions and activities not only to the scientific community, but also to the general public. One consortium decision, part of the incentives for collectors, had major impact on the infrastructure; custodianship over the tissues as well as the tissues stay with the collector institute. Resulting in specimens that are not given to an organization, taking decisions on participation of requests, but instead the local collected tissues stay very easy to access by the collector and allows autonomous negotiation between collector and requestor on cooperation, coauthorship in publication or compensation in costs. Thereby, improving availability of large amounts of high quality samples of a highly specified or rare tumor types and contact opportunities for cooperation with other institutes.

Lead-free multilayer piezoelectric transformer

In this article, a multilayer piezoelectric transformer based on lead-free Mn-doped 0.94(Bi(12)Na(12))TiO(3)-0.06BaTiO(3) ceramics is presented. This piezoelectric transformer, with a multilayered construction in the thickness direction, is 8.3 mm long, 8.3 mm wide, and 2.3 mm thick. It operates in the second thickness extensional vibration mode. For a temperature rise of 20 degrees C, the transformer has an output power of >0.3 W. With a matching load resistance of 10 Omega, its maximum efficiency approaches 81.5%, and the maximum voltage gain is 0.14. It has potential to be used in low voltage power supply units such as low power adapter and other electronic circuits.

TuBaFrost 6: Virtual microscopy in virtual tumour banking

Many systems have already been designed and successfully used for sharing histology images over large distances, without transfer of the original glass slides. Rapid evolution was seen when digital images could be transferred over the Internet. Nowadays, sophisticated Virtual Microscope systems can be acquired, with the capability to quickly scan large batches of glass slides at high magnification and compress and store the large images on disc, which subsequently can be consulted through the Internet. The images are stored on an image server, which can give simple, easy to transfer pictures to the user specifying a certain magnification on any position in the scan. This offers new opportunities in histology review, overcoming the necessity of the dynamic telepathology systems to have compatible software systems and microscopes and in addition, an adequate connection of sufficient bandwidth. Consulting the images now only requires an Internet connection and a computer with a high quality monitor. A system of complete pathology review supporting bio-repositories is described, based on the implementation of this technique in the European Human Frozen Tumor Tissue Bank (TuBaFrost).

TuBaFrost 5: multifunctional central database application for a European tumor bank

Developing a tissue bank database has become more than just logically arranging data in tables combined with a search engine. Current demand for high quality samples and data, and the ever-changing legal and ethical regulations mean that the application must reflect TuBaFrost rules and protocols for the collection, exchange and use of tissue. To ensure continuation and extension of the TuBaFrost European tissue bank, the custodianship of the samples, and hence the decision over whether to issue samples to requestors, remains with the local collecting centre. The database application described in this article has been developed to facilitate this open structure virtual tissue bank model serving a large group. It encompasses many key tasks, without the requirement for personnel, hence minimising operational costs. The Internet-accessible database application enables search, selection and request submission for requestors, whereas collectors can upload and edit their collection. Communication between requestor and involved collectors is started with automatically generated e-mails.

TuBaFrost 1: Uniting local frozen tumour banks into a European network: an overview

TuBaFrost is the consortium responsible for the creation of a virtual European human frozen tumour tissue bank: a collection of high quality frozen residual, accurately classified tumour tissue samples, which are stored in European cancer centres and universities. This virtual tissue bank, searchable on the internet, has rules for access and use, and a code of conduct to comply with the various legal and ethical regulations in European countries. The easy accessibility and the European scale of the bank will result in the availability of a large number of samples even of rarer tumour types. Standardisation of collection, storage and quality control throughout the network is achieved minimising inter-institutional variability. A website providing access to upload, search and request samples is a key tool of the tissue bank. The search engine makes use of virtual microscopy. An overview of the development of the European virtual frozen tissue bank infrastructure is described in this paper. The various key aspects are described in more detail in a series of articles to appear in this Journal.

TuBaFrost 4: access rules and incentives for a European tumour bank

When designing infrastructure for a networked virtual tumour bank (samples remain at the collector institutes and sample data are collected in a searchable central database), it is apparent that this can only function properly after developing an adequate set of rules for use and access. These rules must include sufficient incentives for the tissue sample collectors to remain active within the network and maintain sufficient sample levels in the local bank. These requirements resulted in a key TuBaFrost rule, stating that the custodianship of the samples remains under the authority of the local collector. As a consequence, the samples and the decision to issue the samples to a requestor are not transferred to a large organisation but instead remain with the collector, thus allowing autonomous negotiation between collector and requestor, potential co-authorship in publications or compensation for collection and processing costs. Furthermore, it realises a streamlined cost effective network, ensuring tissue visibility and accessibility thereby improving the availability of large amounts of samples of highly specific or rare tumour types as well as providing contact opportunities for collaboration between scientists with cutting edge technology and tissue collectors. With this general purpose in mind, the rules and responsibilities for collectors, requestors and central office were generated.

TuBaFrost 2: Standardising tissue collection and quality control procedures for a European virtual frozen tissue bank network

Tumour Bank Networking presents a great challenge for oncological research as in order to carry out large-scale, multi-centre studies with minimal intrinsic bias, each tumour bank in the network must have some fundamental similarities and be using the same standardised and validated procedures. The European Human Frozen Tumour Tissue Bank (TuBaFrost) has responded to this need by the promotion of an integrated platform of tumour banks in Europe. The operational framework for TuBaFrost has drawn upon the best practice of standard workflows and operating procedures employed by members of the TuBaFrost project and key initiatives worldwide.

Wavelet-based prognostic model with comparative genomic hybridization (CGH) data in patients with hepatocellular carcinoma (HCC)

20026

Background: In order to obtain a good prognostic model for HCC, clinical data alone may not be adequate. DNA microarray technology has enabled quantification of thousands of genes in a single assay but it has the inborn drawback of high background noise. In order to deal with the problem of information overflow, we developed multivariate dependencies approach using CGH to guide the initial modeling process. This approach takes into account the multivariate nature and potential interaction among the genes during the prognostic modeling process. Methods: The study includes 165 patients with CGH data containing 858 regions/bands. The clinical outcome is survival at 1.72 years. Potential prognostic factors include CGH regions, albumin, ALT, bilirubin, AFP, ascites, alkaline phosphatase (ALP), tumor size, and encephalopathy. We used a blocked wavelet-shrinkage principal component analysis (BWSPCA) to reduce the dimension of CGH data with respect to clinical outcome and followed by logistic regression. We compared the BWSPCA with PCA alone, supervised PCA (Bair et al. 2004), and supervised BWSPCA. Results: Among the 165 patients, 133 (80%) were male, average age of 54.8 years, 78 (47%) stage I-II and 75 (45%) ECOG 0–2. PCA alone and supervised PCA models failed to identify significant CGH regions. BWSPCA model includes tumor size (p = 0.005), albumin (p = 0.047), ALP (p = 0.025), Chr.6q25.1 (p = 0.031), Chr.12q24.32 (p = 0.012), Chr.Xq28 (p = 0.035). Supervised BWSPCA approach includes tumor size (p = 0.016), ALP (p = 0.002), Chr.12q24.11 (p = 0.047). The area under the receiver operating curve (ROC) for the BWSPCA model was 0.78 with a sensitivity and specificity about 0.8 and 0.6 respectively. Conclusions: PCA alone is not effective in identifying CGH regions as prognostic factors. Supervised learning approach did not improve the results. The BWSPCA method identified a number of significant CGH regions associated with survival outcome for HCC patients. These results would be verified in future study. This method will be extended and applied to develop prognostic models using both CGH and DNA microarray data. Acknowledgement: This study is funded by the Research Grant Council of Hong Kong #CUHK4469/03M.

No significant financial relationships to disclose.

Direct decompressive surgery with post-operative radiotherapy (S + RT) versus radiotherapy (RT) alone for the treatment of metastatic epidural spinal cord compression (MESCC): A cost-utility analysis using Ontario health economic data

8570

Background: For selected patients with MESCC, S + RT has recently been shown to improve patients’ ability to ambulate and reduce opioid and corticosteroid use when compared with RT alone, with a trend towards survival benefit. (Patchell et al Lancet 2005) The economic impact of adopting this intervention has not been assessed previously. Methods: An analytic decision model was constructed based on the results from Patchell et al. (2005) The perspective of the public health care insurer of Ontario was adopted for the analysis. Costing was performed by using Ontario data for the following items: surgery, radiotherapy, hospitalization, home care services, palliative hospice, and medications. Utilities were obtained from the Harvard University Catalogue of preference score (HUC) and the Health Outcomes Data Repository Data - Health Utility list (HODaR). The primary analysis is a cost-utility analysis comparing surgery and radiotherapy (S+RT) with radiotherapy alone (RT). A probabilistic sensitivity analysis with Monte-Carlo simulation was performed. Results: When comparing S+ RT with RT alone, the incremental cost-effectiveness ratio (ICER) is CAD$ 43,796 per QALY gained. The cost-utility of S + RT is CAD$ 509,084 per QALY and that of RT alone is CAD$ 2,381,246 per QALY. S + RT costs approximately CAD$ 33 more when compared with RT alone per ambulatory day gained. The cost of surgery is partially offset by the decreased cost of hospice palliative care since more patients remain ambulatory and stay at home. Monte-Carlo simulation showed that there is a 25% chance that S + RT may dominate RT alone. The results are sensitive but generally robust to changes in assumptions about the costs of surgery, home care and palliative hospice care. Conclusions: S+RT is likely cost-effective when compared with RT alone for the treatment of MESCC in selected patients, and should be considered by health care policy makers.

No significant financial relationships to disclose.

An epidemiological study of motor neuron disease in Hong Kong

Worldwide, the incidence of motor neuron disease (MND) has been increasing steadily over recent decades. We reported a follow-up epidemiology study of MND in this locality. We identified the subjects from the computer database of the government hospital system between 1 January 1997 and 31 January 2002 by searching the ICD code starting from 335.xx. Every retrieved case or their records were reviewed and validated by neurologist(s) of the responsible regional hospitals which the patients attended. One hundred and twenty cases from seven regional hospitals (serving 48.05% of the HKSAR population) were identified, validated and confirmed to be MND or related diseases. Ninety-eight new cases were diagnosed during the study period. Average age of onset was 58.76 years; SD 14.12 (28-89) years. Male to female ratio was 1.72:1. Peak age of onset was 60-64 years without sex difference. The adjusted incidence rate was 0.60/100,000/year. The adjusted point prevalence at the prevalence date (31 January 2001) was 3.04/100,000. Despite the incidence and prevalence of MND among Hong Kong Chinese, it remained low compared to worldwide figures, and our data suggested a significant rise of MND or related disease in the last decade. A territory-wide prospective epidemiological study is indicated.

Virtual Microscopy in Virtual Tumor Banking

Many systems have already been designed and successfully used for sharing histology images over large distances, without transfer of the original glass slides. Rapid evolution was seen when digital images could be transferred over the Internet. Nowadays, sophisticated virtual microscope systems can be acquired, with the capability to quickly scan large batches of glass slides at high magnification and compress and store the large images on disc, which subsequently can be consulted through the Internet. The images are stored on an image server, which can give simple, easy to transfer pictures to the user specifying a certain magnification on any position in the scan. This offers new opportunities in histology review, overcoming the necessity of the dynamic telepathology systems to have compatible software systems and microscopes and in addition, an adequate connection of sufficient bandwidth. Consulting the images now only requires an Internet connection and a computer with a high quality monitor. A system of complete pathology review supporting biorepositories is described, based on the implementation of this technique in the European Human Frozen Tumor Tissue Bank (TuBaFrost).

Japanese encephalitis in Hong Kong

OBJECTIVES

To review past and present patterns of occurrence of Japanese encephalitis in Hong Kong and across Asia. A better understanding of the disease should facilitate the formulation of an effective strategic plan to prevent a future epidemic.

DATA SOURCES

Report of local cases, and literature search of MEDLINE up to November 2004.

STUDY SELECTION

Literature and data related to Japanese encephalitis.

DATA EXTRACTION

Relevant information and data were reviewed by the authors.

DATA SYNTHESIS

Since 16 July 2004, under the ordinance of Hong Kong, Japanese encephalitis has been a notifiable disease. In the past, Japanese encephalitis has reached epidemic proportions in Japan, South Korea, and some areas in China. It has spread globally and has a worldwide incidence of 35 000 to 50 000 cases per year with 10 000 deaths. Mortality is about 30% and survivors often suffer serious long-term morbidity. In 2004, there were five local cases of Japanese encephalitis in Hong Kong. Subsequent serological surveillance of serum samples from 1547 local inhabitants revealed that 37 were positive, ie 2.4% of local inhabitants had been exposed to the Japanese encephalitis virus in the past. Most local inhabitants are immunologically naive to Japanese encephalitis virus. Most infections in endemic areas are asymptomatic. Patients with symptomatic Japanese encephalitis usually present with fever, headache, and confusion. Other signs include neurosis, poliomyelitis, and convulsion. Investigations including magnetic resonance imaging, electroencephalography, and single photon emission computed tomography are not specific. A definitive diagnosis depends on serological studies. Treatment is mainly supportive.

CONCLUSIONS

The control of Japanese encephalitis in Hong Kong relies on an accurate surveillance system, vector control, vector avoidance, and vaccination of the at-risk population. At present, vaccination should be limited to travellers to endemic areas who would stay for longer than 1 month.

The halo sign and peripancreatic fluid: useful CT signs of hypovolaemic shock complex in adults

AIM

To report two new, useful computed tomography (CT) signs of the hypovolaemic shock complex (HSC) in adults admitted after blunt abdominal trauma: the halo sign (ring of fluid around a collapsed intra-hepatic inferior vena cava (IVC)), and peripancreatic retroperitoneal fluid.

MATERIALS AND METHODS

CT images of 498 consecutive patients admitted after blunt abdominal trauma were reviewed, of which 27 had CT signs of the HSC. The CT images of these 27 patients were analysed. A control group of 101 patients examined using CT for suspected blunt abdominal trauma who did not have the HSC were chosen for comparison.

RESULTS

The most common features involved the vascular compartment: diminished IVC diameter n = 27 a positive halo sign n = 21 diminished anteroposterior diameter of the aorta n = 13 and abnormal vascular enhancement n = 10. Peripancreatic retroperitoneal fluid in the absence of pancreatic injury, pancreatitis or pancreatic disease was observed in eight patients. Hollow visceral abnormalities included: diffuse increased mucosal enhancement of both the small and large bowel n = 19 diffuse thickening of the small bowel wall n =11 and small bowel dilatation n = 7. Solid visceral abnormalities included both decreased and or increased enhancement. Several concomitant intra- and extra-abdominal injuries were also identified.

CONCLUSION

In the setting of blunt abdominal trauma, early abdominal CT can show diffuse abnormalities due to the HSC, which occasionally may alert clinicians of unsuspected shock. Recognition of these signs as distinguished from injured viscera is important in order to avoid unnecessary laparotomy. Two new signs are described: the halo sign and peripancreatic retroperitoneal fluid.

Clinical features of hereditary spinocerebellar ataxia diagnosed by molecular genetic analysis

OBJECTIVE

To assess the frequency and clinical features of different types of hereditary spinocerebellar ataxia in Hong Kong.

DESIGN

Cross-sectional study using a questionnaire and clinical examination, with the majority of the information retrospectively collected.

SETTING

Three regional hospitals, Hong Kong.

PARTICIPANTS

All patients with spinocerebellar ataxia that was confirmed by molecular genetic tests between January 2001 and October 2003.

MAIN OUTCOME MEASURES

History, latest physical examination results, clinical investigation results, and genetic profiles.

RESULTS

A total of 16 Chinese patients had received diagnoses of spinocerebellar ataxia. These patients had spinocerebellar ataxia type 1 (n=3), spinocerebellar ataxia type 3 (Machado-Joseph disease; n=12), and dentatorubro-pallidoluysian atrophy (n=1). The most common manifestation was ataxia (15/16), followed by pyramidal signs (12/16). Other features such as bulbar dysfunction, ophthalmoplegia, neuropathy, and cognitive impairment were present but variable.

CONCLUSIONS

The clinical manifestations of different types of spinocerebellar ataxia overlap, and genetic study is necessary to confirm the diagnosis. The frequency of spinocerebellar ataxia type 3 is greater than that of other types among these Chinese patients. The age of onset of this type may correlate inversely with the number of CAG repeats.

Isolated ventricular non-compaction presenting with ventricular tachycardia

Isolated ventricular non-compaction is a rare congenital cardiomyopathy, manifested morphologically as prominent myocardial trabeculations and deep inter-trabecular recesses that communicate with the ventricular cavity. Heart failure is the most common presenting condition. Other manifestations include arrhythmia and cardioembolic events. This report is illustrative of isolated ventricular non-compaction in a 78-year-old woman. The diagnosis was made when she presented with ventricular tachycardia many years after a stroke. She subsequently underwent implantation of a cardioverter-defibrillator. This report documents an uncommon presentation of this disease entity in the oldest patient at presentation as yet reported in the literature.

Energy expenditure and physical activity of obese children: cross-sectional study

OBJECTIVES

To investigate the total daily energy expenditure and physical activity pattern of a group of obese and non-obese Hong Kong children.

DESIGN

Cross-sectional study.

SETTINGS

University teaching hospital, Hong Kong.

PARTICIPANTS

Eighteen obese children aged 6 to 17 years and 18 age- and sex-matched non-obese children in the local Hong Kong community.

MAIN OUTCOME MEASURES

Total daily energy expenditure and physical activity pattern were estimated for 3 days using heart rate monitoring. Body composition was measured by dual-energy X-ray absorptiometry.

RESULTS

In obese children, both total fat mass and fat-free mass were greater than in non-obese children. Total daily energy expenditure and its sleep and sedentary components were higher in absolute terms (by 42%, 43%, and 126%, respectively) for obese children. When normalised for body weight, the basal metabolic rate was no different between obese and non-obese children, while the total daily energy expenditure of the obese children was significantly lower (by 22%) than that of non-obese children. When normalised for fat-free mass, the basal metabolic rate and the sedentary component of total daily energy expenditure were significantly higher for obese children. Obese children spent 12% less time asleep, but 51% more time in sedentary activity and 30% less time physically active: a ratio of active-to-sedentary waking time of 0.6 for obese children and 1.9 for non-obese children.

CONCLUSIONS

Although the basal metabolic rate may be influenced by body composition, the finding of a normal basal metabolic rate when normalised for body weight suggests that an intrinsic difference of metabolic rate is not a major contributory cause of obesity. The study pointed particularly to the potential benefit of increasing physical exercise time relative to sedentary activities to reduce the prevalence of childhood obesity. Obese and non-obese children had similar basal metabolic rates when adjusted by fat-free mass and fat mass. Obese children spent more time in sedentary activities.

Cerebral activation by the signals ascending through unmyelinated C-fibers in humans: a magnetoencephalographic study

Cerebral processing of first pain, associated with A delta-fibers, has been studied intensively, but the cerebral processing associated with unmyelinated C-fibers, relating to second pain, remains to be investigated. This is the first study to clarify the primary cortical processing of second pain by magnetoencephalography, through the selective activation of C-fibers, by the stimulation of a tiny area of skin with a CO2 laser. In the hemisphere contralateral to the side stimulated, a one-source generator in the upper bank of the Sylvian fissure (secondary somatosensory cortex, SII) or two-source generators in SII and the hand area of the primary somatosensory cortex (SI) were the optimal configurations for the first component 1M. The onset and peak latency of the two sources in SI and SII were not significantly different. In the hemisphere ipsilateral to the stimulation, only one source was estimated in SII, and its peak latency was significantly (approximately 18 ms on average) longer than that of the SII source in the contralateral hemisphere. From our findings we suggest that parallel activation of SI and SII contralateral to the stimulation represents the first step in the cortical processing of C-fiber-related activities, probably related to second pain.

[Pulmonary problems associated with lymphoplasmacytic lymphoma (Waldenström's macroglobulinemia)]

A 62-year-old man, known for some years due to lymphoplasmacytic lymphoma, was admitted with progressive dyspnoea. Multiple lung infiltrates were found upon X-ray examination. Because of the suspicion of an infection, a bronchoscopy with bronchoalveolar lavage was performed. No infectious cause could be established. Upon cytological examination, a highly increased level of kappa-positive B-lymphoid cells was found, as is seen in cases of lymphoplasmacytic lymphoma (Waldenström's macroglobulinaemia). Following chemotherapy, the dyspnoea lessened and the pulmonary infiltrates disappeared. In patients with a lymphoproliferative disorder, pulmonary infiltrates due to infection are found relatively frequently. This case report highlights a rare complication of the disease, namely pulmonary infiltrates caused by infiltration of lymphoplasmacytic cells, emphasising the importance of cytological examination of broncho-alveolar lavage fluid.

Adhesion of epithelial cells to fibronectin or collagen I induces alterations in gene expression via a protein kinase C-dependent mechanism

Adhesion of human salivary gland (HSG) epithelial cells to fibronectin- or collagen I gel-coated substrates, mediated by beta1 integrins, has been shown to upregulate the expression of more than 30 genes within 3-6 h. Adhesion of HSG cells to fibronectin or collagen I for 6 h also enhanced total protein kinase C (PKC) activity by 1.8-2.3-fold. HSG cells expressed PKC-alpha, gamma, delta, epsilon, mu, and zeta. Adhesion of HSG cells to fibronectin or collagen I specifically activated PKC-gamma and PKC-delta. Cytoplasmic PKC-gamma and PKC-delta became membrane-associated, and immunoprecipitated PKC-gamma and PKC-delta kinase activities were enhanced 2.5-4.0-fold in HSG cells adherent to fibronectin or collagen I. In addition, adhesion of fibronectin-coated beads to HSG monolayers co-aggregated beta1 integrin and PKC-gamma and PKC-delta but not other PKC isoforms. Thus, integrin-dependent adhesion of HSG cells to fibronectin or collagen I activated PKC-gamma and PKC-delta. The role of this PKC upregulation on adhesion-responsive gene expression was then tested. HSG cells were treated with the specific PKC inhibitor bisindolylmaleimide I, cultured on non-precoated, fibronectin- or collagen I-coated substrates, and analyzed for changes in adhesion-responsive gene expression. Bisindolylmaleimide I strongly inhibited the expression of seven adhesion-responsive genes including calnexin, decorin, S-adenosylmethionine decarboxylase, steroid sulfatase, and 3 mitochondrial genes. However, the expression of two adhesion-responsive genes was not affected by bisindolylmaleimide I. Treatment with bisindolylmaleimide I did not affect cell spreading and did not significantly affect the actin cytoskeleton. These data suggest that adhesion of HSG cells to fibronectin or collagen I induces PKC activity and that this induction contributes to the upregulation of a variety of adhesion-responsive genes.

Attention and visual interference stimulation affect somatosensory processing: a magnetoencephalographic study

In our previous study, continuous visual (cartoon and random dot motion) and auditory (music) stimulation changed the somatosensory evoked magnetic fields following electrical stimulation of the median nerve in human subjects. They enhanced the middle-latency components (3M and 4M) generated in the contralateral primary somatosensory cortex, and reduced the MI component generated in the ipsilateral secondary somatosensory cortex. We speculated that such interference effects were caused by activation of polymodal neurons in areas 5 and/or 7 of the parietal lobe as well as in the medial superior temporal region and superior temporal sulcus. However, we could not exclude the effect of attention on such interference effects. In the present study, to know the effect of attention on visual and auditory interference in these changes, we stimulated the bilateral median nerves unilaterally in a random order, and asked subjects to count the number of times the left median nerve was stimulated while visual or auditory interference was applied. Five components (1M-5M) were identified in the hemisphere contralateral to the stimulated nerve and only one component (MI) was found in the ipsilateral hemisphere. The 3M and 4M components (33-75 ms in latency) were enhanced by both attention and visual interference stimulation but not by auditory stimulation. The 5M component (70-115 ms) and MI component (70-133 ms) were enhanced by attention, but were not changed by attention together with visual or auditory interference. Summarizing the results of our previous study and the present study, (1) visual interference alone enhanced the 3M and 4M but reduced the MI, and (2) attention alone also enhanced the 3M and 4M, and enhanced the 5M and MI. As a result, (3) visual interference with attention enhanced the 3M and 4M more, and showed no significant change of the 5M and MI. This was compatible with a summation of the effects caused by visual interference alone and attention alone, but some interactions between visual interference and attention might have taken place. The locations of dipoles of all components were not significantly changed by attention or any interference stimulation. These findings support the idea that there are significant interactions of activities relating to somatosensory stimulation, visual stimulation and cognitive function, in both the primary and the secondary somatosensory cortex in humans.

A new method for measuring the conduction velocities of Abeta-, Adelta- and C-fibers following electric and CO(2) laser stimulation in humans

The conduction velocities of Abeta-, Adelta- and C-fibers of a peripheral nerve of the upper limb in normal subjects were measured by a combination of conventional electric stimulation, painful CO(2) laser stimulation and non-painful CO(2) laser stimulation of a tiny skin surface area, respectively. The values obtained were 69.1+/-7.4 m/s, 10.6+/-2.1 and 1.2+/-0.2 m/s, respectively. These findings demonstrated that the combined methods are useful for experimental and clinical exploration of the physiological function and pathophysiological role of Abeta-, Adelta- and C-fibers of a given peripheral nerve.

[Cumulative impact assessment: problems and practice in China mainland and Hong Kong]

Including past, present and future impacts in environmental impact assessment (EIA) of the proposed action, it is the important property of cumulative impact assessment (CIA) that different from traditional EIA. It is also the main trend of EIA improvement. From the area of regulation demands, documentation practice, spatial and temporal boundary, key contents and mitigation measures, this paper analyses the status of CIA both of China Mainland and Hongkong in the practice of EIA. The author suggested that technical guidelines for cumulative effects assessment should be set up in China Mainland and Hongkong, CIA should be included in project, region and strategy environment assessment and cumulative impacts should be list clearly in EIA study executive summary and reported in a separate part of the environmental consequences section. Spatial and temporal boundaries and any cumulative impacts addressed within the CIA process should be provided evidence or analysis to support the conclusion. In order to prevent cumulative effects effectively, the focus on CIA should be put on biodiversity, social and economic impacts and global environmental effects.

Malignant insulinoma with hepatoid differentiation: a unique case with alpha-fetoprotein production

Hepatoid carcinomas are uncommon extra-hepatic neoplasms exhibiting features of hepatocellular carcinoma and they are most frequently described in the stomach. We report a 64-year-old woman with a malignant insulinoma showing focal hepatoid differentiation and biochemical evidence of alpha-fetoprotein (AFP) production. The current case is the first malignant insulinoma with hepatoid differentiation. Resection of the primary tumor followed by regional embolization was peformed. The patient died 22 months after initial presentation. Thus, the presence of hepatoid differentiation in pancreatic tumor should be noted as the tumor may be associated with elevated AFP. The features of pancreatic hepatoid carcinomas are discussed.

Transradial coronary angioplasty and stenting--immediate results and 3-month clinical follow-up in the first 50 patients performed at the National Heart Institute

AIM

To explore the safety and feasibility of coronary angioplasty and stenting via the radial artery in a heterogenous group of patients and to report the immediate and 3-month clinical follow-up.

BACKGROUND

The use of the transradial approach for coronary angiography was first described by Lucien Campeau in 1989. Based on the favourable initial results, this technique has gained widespread acceptance worldwide. Ferdinand Kiemeneij's work in transradial angioplasty and stenting has taken invasive cardiology into the exciting new era of "minimally invasive coronary intervention".

METHODS AND RESULTS

Fifty consecutive patients underwent Transradial Percutaneous Transluminal Coronary Angioplasty (PTCA) with or without stenting from mid March 98-December 98. The right radial approach was utilised in 41 patients (80%) while the left in 9 patients. Ninety percent of the procedures was done on an adhoc basis. Diabetes mellitus was present in 38% of patients. Eighty percent of patients had unstable angina pectoris and 60% had a prior history of acute myocardial infarction. The commonest vessel involved was the LAD (51%) and type B lesions predominated (54%). PTCA was successful in 96%. One patient had a total LAD occlusion, which could not be wired, and another developed severe spasm during catheter manipulation. The latter had successful PTCA via the right femoral route Stents were utilised in 57% of patients. The commonest indication for stenting was suboptimal PTCA results (89%) and dissection (14%). There was no stent embolisation and all stents were successfully deployed (100%). One patient developed acute stent thrombosis necessitating repeat PTCA and another patient sustained an acute anteroseptal myocardial infarction 5 days post procedure as a result of subacute stent thrombosis and died. Two patients had successful primary PTCA. There was no bleeding or vascular complications. 60% of patients were treated on an outpatient basis. At 3-months follow up, 1 patient required CABG's for disease progression. Three patients had absent radial pulses without adverse consequence. No patient required repeat PTCA at follow up.

CONCLUSION

In summary, adhoc PTCA and stenting is safe and feasible in our patient population. A study on the cost effectiveness of the procedure compared to conventional femoral PTCA is warranted.

Anaerobic bacteria and intrahepatic stones: detections of Clostridium sp. and Bacteroides fragilis

OBJECTIVE

To detect anaerobic bacteria Clostridium sp. and Bacteroides fragilis in intrahepatic stones by molecular genetic method.

METHODS

DNA was extracted from 59 stone samples and subjected to polymerase chain reaction (PCR) amplification targeting the 16S rRNA gene of Clostridium sp. and the glutamine synthetase gene of Bacteroides fragilis. Single-strand conformational polymorphism (SSCP) analysis was performed to identify the Clostridium sp.

RESULTS

16S rRNA gene sequences for Clostridium sp. were identified in 49 stones (83%, 49/59). The two most common groups were detected in 19 (41%) and 17 (37%) of the 46 samples using SSPC analysis, and 25/59 (42%) stones were tested positive for Bacteroides fragilis.

CONCLUSIONS

Anaerobes such as Clostridium sp. and Bacteroides fragilis present in intrahepatic stones and may play a role in stone formation. PCR is a useful technique to detect fastidious pathogens, which are difficult to culture. SSCP of PCR products is a rapid method in differentiating bacterial species.

Is prophylactic ciprofloxacin effective in delaying biliary stent blockage?

BACKGROUND

Late stent blockage is a major complication of endoscopic stent insertion for malignant obstructive jaundice. Stents block as a result of bacterial infection and biofilm formation. We report a randomized but unblinded study using an animal model to evaluate the effect of prophylactic ciprofloxacin, which selectively suppresses gram-negative bacteria, in an attempt to prolong stent patency.

METHOD

Ten adult cats underwent surgical implantation of 5F polyethylene stents through common bile duct strictures created around the choledochotomy, with the tip of the stent left in the duodenum. Five animals received intravenous ciprofloxacin perioperatively and were then maintained on oral ciprofloxacin 25 mg twice daily. Control cats were not given antibiotics. The animals were sacrificed when signs of biliary obstruction or cholangitis persisted for more than 3 days or at the end of the 16-week study period. Stents were removed and examined for patency. In addition, the stents were cultured to recover the adherent bacteria.

RESULTS

All control animals developed stent blockage within 4 weeks. Two ciprofloxacin-treated cats developed stent blockage at 21 and 42 days, respectively, whereas the other 3 cats had patent stents for the entire study period. There was a significant difference between the median stent patency of 112 days for the ciprofloxacin group versus 16 days for the control group (p < 0.02). Bacteriologic cultures showed that the bile and blocked stents from the control group had predominantly gram-negative bacteria, whereas the bile and stents of the ciprofloxacin group had gram-positive and anaerobic bacteria, with an absence of gram-negative bacteria (p < 0.01).

CONCLUSION

Ciprofloxacin prophylaxis eliminates gram-negative bacterial infection in bile and minimizes sludge formation and may have a potential benefit in delaying stent blockage.

The somatosensory evoked magnetic fields

Averaged magnetoencephalography (MEG) following somatosensory stimulation, somatosensory evoked magnetic field(s) (SEF), in humans are reviewed. The equivalent current dipole(s) (ECD) of the primary and the following middle-latency components of SEF following electrical stimulation within 80-100 ms are estimated in area 3b of the primary somatosensory cortex (SI), the posterior bank of the central sulcus, in the hemisphere contralateral to the stimulated site. Their sites are generally compatible with the homunculus which was reported by Penfield using direct cortical stimulation during surgery. SEF to passive finger movement is generated in area 3a or 2 of SI, unlike with electrical stimulation. Long-latency components with peaks of approximately 80-120 ms are recorded in the bilateral hemispheres and their ECD are estimated in the secondary somatosensory cortex (SII) in the bilateral hemispheres. We also summarized (1) the gating effects on SEF by interference tactile stimulation or movement applied to the stimulus site, (2) clinical applications of SEF in the fields of neurosurgery and neurology and (3) cortical plasticity (reorganization) of the SI. SEF specific to painful stimulation is also recorded following painful stimulation by CO(2) laser beam. Pain-specific components are recorded over 150 ms after the stimulus and their ECD are estimated in the bilateral SII and the limbic system. We introduced a newly-developed multi (12)-channel gradiometer system with the smallest and highest quality superconducting quantum interference device (micro-SQUID) available to non-invasively detect the magnetic fields of a human peripheral nerve. Clear nerve action fields (NAFs) were consistently recorded from all subjects.

Magnetic response of human extrastriate cortex in the detection of coherent and incoherent motion

Although direction selectivity is a cardinal property of neurons in the visual motion detection system, movement of numerous elements without global direction (incoherent motion) has been shown to activate human and monkey visual systems, as does coherent motion which has global direction. We used magnetoencephalography to investigate the neural process underlying responses to these types of motions in the human extrastriate cortex. Both motions were created using a random dot kinematogram and four speeds (0, 0.6, 9.6 and 25 degrees /s). The visual stimuli were composed of two successive motions at different speeds; a coherent motion at a certain speed that changed to incoherent motion at another speed or vice versa. Magnetic responses to the change in motion consisted of a few components, the first of which was always largest. The peak latency of the first component was inversely related to the speed of the preceding motion, but for both motions it was not affected by the speed of the subsequent motion. For each subject, the estimated origin of the first component was always in the extrastriate cortex, and this changed with the speed of the preceding motion. For both motions, the location for the slower preceding motion was lateral to that for the faster preceding motion. Although the latency changes of the two motions differed, their overall response properties were markedly similar. These findings show that the speed of incoherent motion is represented in the human extrastriate cortex neurons to the same degree as coherent motion. We consider that the human visual system has a distinct neural mechanism to perceive random dots' motion even though they do not move in a specific direction as a whole.

Synthesis of a new chiral ligand, 6, 6'-dihydroxy-5, 5'-biquinoline (BIQOL) and its applications in the asymmetric addition of diethylzinc to aldehydes

A new chiral ligand 6, 6'-dihydroxy-5, 5'-biquinoline (BIQOL, 2) was prepared via Cu2+ mediated coupling. The resolution was carried out by separating the corresponding ditrifluomethanesulfonate on chiral column. When applied to the enantioselective addition of diethylzinc to aromatic aldehydes, this ligand induced the reaction with enantioselectivity equivalent to that induced by BINOL. The effects of solvent and reaction temperature on enantioselectivity were also studied.