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The precipitation of poly(vinyl acetate) (PVAc) during the cure of vinyl ester resins and unsaturated polyester resins has been studied. The rate of polymerization, measured by differential scanning calorimetry, was virtually independent of the PVAc additive and the activation energy (at the peak rate) was approximately constant at 70 kJ mol−1, in agreement with theoretical estimates. A turbidity technique was found to be useful in studying the phase precipitation process. The start of phase precipitation was found to be strongly correlated with the start of the polymerization process and the end of the induction stage. The induction stage was shown to be caused by radical consumption by the inhibitor in the resin. The onset time for phase precipitation was shown to be proportional to inhibitor concentration and reciprocally related to the initiator concentration. The activation energy for the onset of phase precipitation, calculated by isothermal or scanning techniques, was close to the activation energy for initiator decomposition as predicted. Dynamic mechanical thermal analysis confirmed the occurrence of phase separation in the cured resins and suggested that a co-continuous morphology was developed around 5 wt% PVAc.

The microstructure and properties of Cu-C pseudoalloy films prepared by R.F. magnetron sputtering have been investigated. As Cu and C are mutually immiscible, nonequilibrium supersaturated solid solutions of C in Cu with nanocrystalline microstructures were observed in as-deposited films. Upon heating of the films, three major transition events took place. Recovery occurred at ∼280 to 300 °C, while at ∼400 °C, crystallites started to growth and coalescence, due to the release of strain energies stored during deposition. Annealing at above 600 °C led to the occurrence of grain growth and altered the microstructure considerably. Although attempts have been made in this study, a possible annealing-induced phase separation could not be unambiguously identified. Yet, the fact of low twin densities and fine grain structures observed in the annealed films suggests that the extensive grain growth was impeded by the presence of carbon. Resistivity and hardness properties correlated well with the film microstructure and were governed by the impurity effect of carbon. Low-carbon Cu-C films yielded relatively low resistivity, attributable to the improved film microstructure. Hardness results indicated the strengthening of films was mainly due to fine structure, presence of carbon, and grain refinement by annealing twins.

BACKGROUND Many patients with carcinoma of the pancreas die because their disease is not detected until late in its course. Methods that detect these cancers earlier will improve patient outcome. Over 80% of pancreatic carcinomas contain mutations in codon 12 of the K-ras gene. Screening duodenal fluid for these mutations may lead to early detection of these cancers and assist in establishing a diagnosis of pancreatic carcinoma. METHODS Polymerase chain reaction (PCR), with and without restriction enzyme-mediated mutant enrichment, was performed on DNA isolated from duodenal fluid specimens from 61 patients who underwent pancreaticoduodenectomy (Whipple's operation) for either periampullary cancer or a benign condition of the pancreas. Representative sections of pancreas pathology (primary carcinoma, benign tumor, or chronic pancreatitis) from the patients with duodenal fluid specimens containing amplifiable DNA were also analyzed for K-ras mutations. Wild-type and mutant K-ras were detected by hybridization of the PCR products with K-ras codon 12 mutant and wild-type specific probes. RESULTS Seven of the 61 duodenal fluid specimens contained DNA that did not amplify. Thirteen (24% of the 54 duodenal fluid specimens with amplifiable DNA and 21% of the total of 61 specimens) contained activating point mutations at codon 12 of the K-ras gene. Mutations were detected in 13 of the 51 duodenal fluid specimens from patients with cancer (sensitivity, 25%), whereas mutations were not detected in any of the 9 amplifiable duodenal fluid specimens from patients with benign conditions of the pancreas (specificity, 100%). One duodenal fluid specimen from a patient with adenocarcinoma of the pancreas had two different K-ras mutations. DNA from three of the primary carcinomas did not amplify or was not available. Twenty-nine (69%) of the 42 primary tumors with amplifiable DNA contained K-ras mutations, whereas 3 (30%) of the 10 pancreata with benign conditions harbored mutations. Twenty-two (65%) of 34 ductal adenocarcinomas of the pancreas with amplifiable DNA had K-ras mutations. It is noteworthy that the same mutation was present in both the duodenal fluid and the primary carcinomas of 11 (92%) of the 12 patients who had primary tumors with amplifiable DNA as well as K-ras mutations in their duodenal fluid specimens. CONCLUSIONS The identification of genetic alterations in cancer-causing genes in duodenal fluid may form the basis for the development of new approaches to the detection of carcinoma of the pancreas. Some pancreata without cancer, however, may also harbor K-ras mutations, potentially limiting the specificity of K-ras-based tests. Cancer 1998;82:96-103. © 1998 American Cancer Society.

The initial stages of oxidation of AlAs(001) (using H2O and O2 as the oxidants) have been investigated using Auger electron spectroscopy, temperature-programmed desorption and high-resolution electron energy-loss spectroscopy. We have found that O2 has a low probability of dissociative chemisorption on AlAs(001), rendering it ineffective as an oxidant of AlAs under ultrahigh vacuum conditions. In contrast, water, by virtue of overlapping desorption and dissociation temperatures, is able to dissociate readily on the AlAs(001) surface. Water dissociation within the subsurface is observed, indicative of Al oxide/hydroxide formation. Arsenic is found to be depleted within the oxide film by arsine desorption, a process which is shown to enhance the oxide growth. By identifying the various reaction steps which occur (with annealing) after the low-temperature adsorption of water on AlAs(001), we are able to propose a mechanism for the initial stages of wet AlAs oxidation. Briefly, the initial H2O adsorption occurs molecularly at 100 K. Upon annealing to 160 K, both desorption and dissociation from the molecularly adsorbed state occurs. Both AlO and AlOH, as well as AsH, are produced by the dissociation of H2O (via partial and total dehydrogenation, respectively). The AlOH species disproportionate and/or rehydrogenate between 400 and 650 K resulting in H2O desorption. The remaining AlOH dehydrogenate above 550 K to produce AlO and desorbing hydrogen. The AsH species desorb as AsH3 in a broad peak at 500–550 K with an additional low-temperature desorption peak appearing below 200 K after higher H2O exposures.

A low resolution 1H NMR (Nuclear Magnetic Resonance) system having 4.1 MHz was constructed to measure moisture contents (MC) of rice nondestructively. Mass-dependent and mass-independent models of the MC measurement were developed. The mass-dependent model had a Standard Error of Calibration (SEC) of 0.467% and a Standard Error of Prediction (SEP) of 0.513%. The mass independent model had a SEC of 0.970% and a SEP of 1.10%. In the range of temperature measured (14°C, 21°C), the sample temperature did not affect the MC measurement. The results demonstrated that a low resolution NMR system which had a relatively inhomogeneous (1000 ppm) magnet could be used for nondestructive MC measurements of rice.

Active vibration control of an axially moving string by wave cancellation is presented. The control problem is formulated in the frequency domain. An exact, closed-form expression for the transfer function of the closed-loop system, consisting of the flexible structure, a feedback control law and the dynamics of the sensing and actuation devices, is derived. It is shown that all vibration modes can be stabilized and that the controlled system has no resonance. Moreover, the designed controller is applicable to the control of the string transverse vibration under various kinds of loading and constraint conditions. Results for the response of the controlled string under different excitations are presented and discussed along with the wave propagation and cancellation characteristics.

Aims This study was designed to assess the efficacy and safety of a dipeptidyl peptidase-4 inhibitor, gemigliptin versus sitagliptin added to metformin in patients with type 2 diabetes. Methods We conducted a double-blind, randomized, active-controlled trial in 425 Asian patients with inadequately controlled type 2 diabetes being treated with metformin alone. Eligible patients were randomized into three groups: 50 mg gemigliptin qd, 25 mg gemigliptin bid or sitagliptin 100 mg qd added to ongoing metformin treatment for 24 weeks. Haemoglobin A1c (HbA1c) and fasting plasma glucose (FPG) were measured periodically, and oral glucose tolerance tests were performed at baseline and 24 weeks after starting the treatment regimen. Results Twenty-four weeks later, adding gemigliptin (50 mg/day) to ongoing metformin therapy significantly improved glycaemic control. Reduction in HbA1c caused by 50 mg gemigliptin qd (−0.77% ± 0.8) was non-inferior to that caused by 100 mg sitagliptin qd (−0.8% ± 0.85). Proportion of patients achieving HbA1c

The present study was aimed to compare the hemodynamic flow characteristics of LIMA radial artery composite sequential bypass grafting and with single LIMA and saphenous vein sequential bypass grafting performed by off-pump coronary artery bypass grafting (OPCAB).Between March 2007 and February 2008, 121 OPCAB patients were prospectively divided into two groups; Group I (N.=70, left internal thoracic artery [LITA]-left anterior descending [LAD] and Ao-SV sequential grafting), and Group II (N.=51, LITA-RA sequential grafting). The mean flow, pulsatility index (PI) and back flow (BF) were measured using the Transit-time flow meter (TTFM). In Group II, the proximal (p-LITA) and distal LITA (d-LITA) flow in relation to the RA side branch anastomosis were measured separately.The mean flow and PI of the proximal SV sequential graft and that of the RA graft were 64.4 ± 37.3 mL/min and 2.6 ± 1.6 versus 27.3 ± 18.6 mL/min and 4.1 ± 4.4, respectively (P0.05). In Group I, the mean LITA flow, PI, and BF were 26.9 ± 16.4 mL/min, 2.6 ± 1.5, and 3.1 ± 6.1% whereas in Group II those of the p-LITA were 37.3 ± 21.6 mL/min, 2.3 ± 1.0, and 2.0 ± 3.5% and the d-LITA were 18.8 ± 12.2 mL/min, 3.9 ± 3.3 and 7.4 ± 11.8% (P0.01).The results of the present data suggest the hemodynamic flow characteristics of composite bypass grafting to be inferior to the single LIMA and separate aorta-saphenous vein bypass grafting strategy. However, a longer follow up is warranted to assess the implications of these findings on graft durability.

In this paper, the application of the transfer function formulation and the generalized displacement method (GDM) to the analysis of constrained distributed parameter systems is illustrated. Two kinds of classical examples are considered. In the constrained free-free beam example, it is shown how the GDM gives the eigensolutions without requiring knowledge of the normal modes of the unconstrained beam. In the string on a partial elastic foundation example, mode localization and eigenvalue loci veering phenomena are examined. It is shown that mode localizaation can occur in spatially symmetric systems and for modes whose frequency loci do not veer.

Analysis of constrained distributed parameter systems by the transfer function formulation is presented. The methodology is suitable for symbolic computation coding. The distributed system is an assembly of distributed elements. A generalized displacement method (GDM) is developed to evaluate the free and forced responses of the system. It is shown that, while classical methods require the satisfaction of both the displacement and force boundary conditions at the subsystem interfaces, GDM only needs to impose generalized force constraints. The continuity of generalized displacements at the interfaces is embedded in the present formulation. Thus, computation efforts are greatly reduced, in particular, for systems with a large number of distributed subsystems. Eigenfunctions of constrained systems are obtained by solving a finite-dimensional eigenvalue problem governing the generalized coordinate vector. The formulation can be applied to damped and non-selfadjoint systems.

We have measured the resistivity as a function of temperature in a magnetic field at various field angles θ for oxygen-deficient YBCO films and ultrathin YBCO films; θ is the angle between the crystalc axis and the direction of the magnetic field. The angular dependence of the critical field,Hc2, shows a cusplike behaviour at θ=90° for the oxygen-deficient 60 K YBCO films indicating that the Cu-O2 layers are two-dimensional in nature. BothTc versus θ in a constant field andHc2 as a function of θ show a plateau at θ=90° for 83 K (zero resistance) ultrathin YBCO films with a thickness of 20 units of the YBCO cell; these results indicate that there is a coupling between the Cu-O2 layers. The dimensionality of the Cu-O2 layers in oxygen-deficient YBCO films and ultrathin YBCO films is discussed in terms of the anisotropic Ginzburg-Landau model and the Tinkham thin-film model.

We report results of systematic investigation of impurities in dielectrics and hydrogen barriers (Ti and Al2O3 films) during the integration process of SrBi2Ta2O9-based ferroelectric memories. The capacitors integrated with Ti hydrogen barriers are not electrically degraded regardless of the annealing conditions of the subdielectrics. On the contrary, electrical properties of the capacitors using Al2O3 hydrogen barriers significantly depend on the annealing temperatures for subdielectrics. It turned out that interaction of the dielectrics with plasma during sputtering of the Ti films caused fragmentation of the moisture in the dielectrics and absorption of the hydrogen in the Ti films, making annealing irrelevant. However, the alumina films blocked both hydrogen and moisture in the subdielectrics during the passivation process, resulting in dependence on the annealing temperatures.

The aim of this study was to evaluate the efficacy of ondansetron and ramosetron in the reduction of post-operative nausea and vomiting (PONV) associated with patient-controlled analgesia (PCA) after cardiac surgery.A total of 320 patients scheduled for elective cardiac surgery were enrolled. Patients were randomly assigned to one of four treatment regimens (n=80 in each group): no prophylactic antiemetics (group P); intravenous (i.v.) ondansetron 4 mg at the end of surgery and 12 mg added to PCA (group O); i.v. ramosetron 0.3 mg at the end of surgery and no antiemetics added to PCA (group R1); and i.v. ramosetron 0.3 mg at the end of surgery and 0.6 mg added to PCA (group R2).The incidence of PONV during the 48-h post-operative period was lower in groups O (46%), R1 (54%), and R2 (35%) compared with group P (71%, P0.001). The incidence and severity of nausea were lower in groups O, R1, and R2 than in group P during the 24-h post-operative period, whereas the incidence and severity of nausea during 24-48 h after surgery were lower in groups O and R2, but not in group R1, than in group P. Compared with group P (53%), the frequency of rescue antiemetic usage was significantly lower in groups O (34%) and R2 (29%), but not in group R1 (43%).The addition of either ondansetron or ramosetron to PCA can reduce the incidence of PONV during 48 h after cardiac surgery.

To determine whether in the local lay Hong Kong population, video self-instruction about cardiopulmonary resuscitation has comparable results to traditional classroom instructions.Prospective randomised single-blind controlled trial.A first-aid training organisation in Hong Kong.Cantonese applicants for cardiopulmonary resuscitation courses aged between 18 and 70 years were recruited into the study. They were randomised into two groups. Those selected for self-learning were given a kit (consisting of a mini-manikin, a video compact disc, and an instruction manual) and sent home. The other group underwent usual classroom training. Both groups were examined together; the examiners remained blinded to the background training of the subjects. Those who passed were asked to come back for re-examination after 1 year.The examination passing rates initially and after 1 year.During a 1-year period between 1 April 2007 to 31 March 2008, 256 subjects were recruited into this study, 124 for self-learning and 132 for classroom training. The age range was 18 to 62 (mean, 39; standard deviation, 10) years. There was no significant difference in passing rate between the two groups at the initial examination or at the re-examination after 1 year. Notably, 28 (23%) of the participants of the self-learning group taught cardiopulmonary resuscitation to relatives and friends.Video self-learning resulted in cardiopulmonary resuscitation performance as good as traditional classroom training.

A 59-year-old female patient with adult onset Still's disease (AOSD) presented with hemoptysis and pseudoaneurysm from an aortic root vent cannulation site that was created 4 years earlier for combined mitral and aortic valve surgery. The pseudoaneurysm was successfully repaired and the patient remained well during a follow-up period of 20 months.

Through-silicon-via (TSV) becomes an emerging interconnection technology with various TSV structures, among which the annular-TSV demonstrates great application potentials because of its simple manufacturing processes and low cost. Due to the mismatch of coefficient of thermal expansion (CTE) among various materials leading to various quality and reliability issues, it is necessary to develop a novel modeling/simulation approach to help with optimizing annular-TSV structures and process parameters because the plated-Cu uniformity highly depends on Cu-plating solution, plating process and via location. Therefore, a novel sequential electro-chemical and thermo-mechanical simulation methodology was developed with simulation procedures as the electro-chemical analyses to simulate Cu-plating process, followed by the thermo-mechanical analyses (from wafer-level model, chip-level model to via-level model) to simulate key TSV insulation/plating processes using global-local and death-birth simulation methods. Based on the novel simulation methodology, this work studied the variations of plated-Cu thickness and found the stress of annular-TSVs near wafer edge was larger than that at wafer center by 16%~18% due to the Cu-plating non-uniformity. The stress of annular-TSVs would increase by 10%~31% and by 9%~27% if reducing the Cu seed thickness from 2um to 0.5um and reducing the via pitch from 300um to 150um, respectively.

Through-silicon-via (TSV) technology has been demonstrated to be capable of being applied into many microelectronics products, e.g., CMOS image sensor (CIS), DRAM, flash memory, 3D-MEMS, RF-SiP, logic-SiP, LED, etc. However, new IC design is needed to implement the TSV interconnect into a chip and the specific TSV line is required for TSV fabrication, the facts of long time needed for new IC design qualification and implementation plus big facility investment required for setting-up a full functional TSV line result in high manufacturing cost which further hinders the applications of TSV interconnect technology into many products, e.g., DRAM and flash memory. In this paper, a new TSV-based interconnect technology, named under-pad interconnect (UPI), has been developed for 3D-stacking of NAND flash memory chips using existing CMOS-compatible processes. The basic idea is to use the existing wire-bonding (WB) based NAND flash memory wafer to fabricate blind-via interconnect under bond pad from the backside of a wafer, followed by stacking the chips with UPIs onto the substrate to build a 3D-module. The details of the fabrication process development and the NAND flash memory 3D-stacking methodology will be reviewed and discussed.

The cDNAs encoding two major subunits, named YC1 and YC7-alpha, of yeast proteasomes (multicatalytic proteinase complexes) were isolated and sequenced. As deduced from their nucleotide sequences, YC1 and YC7-alpha consist of 288 and 252 amino acid residues with calculated molecular weights of 31,534 and 27,999, respectively. They showed marked sequence homology to other eukaryotic proteasome components, suggesting that proteasomes are composed of a family of subunits with the same evolutional origin. To obtain information on the physiological role of proteasomes, we disrupted the chromosomal genes of YC1 and YC7-alpha of yeast cells independently, using isolated cDNA clones. Disruption of the coding region of one copy of the YC1 gene in diploid yeast created a recessive lethal mutation, but disruption of the 3'-noncoding region of the gene had no effect on cell proliferation. Disruption of the YC7-alpha gene also had a lethal effect on haploid yeast cells. These findings demonstrated that YC1 and YC7-alpha are both encoded by a single copy gene and that these genes are essential for proliferation of yeast cells.

This is a retrospective study on the prevalence of diverticulosis in Hong Kong Chinese adults. Eight-hundred and fifty-eight consecutive barium enema examinations over a period of 18 months (January 1995-June 1996) were analysed. Results show that the prevalence of diverticulosis in our community is 25.1% with no significant difference between male and female adults. The prevalence is lower than Western countries but higher than in Asia. Moreover, the peak prevalence is at the 50-79 years age group with lower prevalence in the older age groups. This may be explained by the rapid rise in prevalence in the younger age groups so that the age-related increase in prevalence become obscured. We postulate that this may be due to Western cultural influence in our diet and lifestyle. There is no significant difference in the symptomatology of patients with and without diverticulosis, supporting the idea that diverticulosis alone is usually asymptomatic. There is predominance of right hemicolon involvement in our subjects, in contrast to the left hemicolon predominance in the Caucasian population. Of patients with diverticulosis, 55.3% have only right-sided involvement and 32.6% have bilateral involvement. Only 12.1% of patients with diverticulosis have exclusively left hemicolon involvement. Caecal and ascending colon diverticula are found in 6.4% and 17.6% of all the adults under study, respectively. Clinicians caring for patients from our community should take note of this high frequency of caecal and ascending colon diverticulosis as caecal and ascending colon diverticulitis is notoriously difficult to diagnose clinically.

The initial oxidation process of the ultraclean $\mathrm{Si}(001)\mathrm{\text{\ensuremath{-}}}c(4\ifmmode\times\else\texttimes\fi{}2)$ surface is studied using scanning tunneling microscopy at low temperature. At the early stage of oxygen adsorption, reactions with Si atoms at ${S}_{B}$ steps are dominant over those at terraces by more than 2 orders of magnitude, and they proceed in two distinct stages to high oxidation states. Guided by the ab initio calculations, the oxidation structures at each stage are proposed. The extreme reactivity of the step edge is due to the presence of rebonded adatoms with dangling bonds and weak rebonds, and their proximity allows the formation of -Si-O- chain structures along the step edge, unlike those on the Si(111) surface.

To examine the epidemiology of penile 'fracture' and its presenting characteristics in the local population.Retrospective study.District hospital, Hong Kong.Patients with a discharge diagnosis of 'fractured' penis during a 7-year period from August 1998 to August 2005.Age, time of attendance, cause, symptoms, signs, emergency department diagnosis, site of rupture, operative findings, and final outcome.A total of 11 patients were identified. The mean age was 44 years (range, 30-63 years). The interval between time of injury and presentation ranged from 17 minutes to 7 days. Seven (64%) cases were attributed to sexual intercourse, three (27%) to penile manipulation, and one (9%) to rolling over the erect penis during sleep. Ten patients underwent surgery; all had primary suturing of the tunica tear, while two also required primary urethral repair. At follow-up, three (27%) patients had erectile dysfunction, one had mild penile deformity and one had a mild urethral stricture.Emergency physicians and surgeons, as well as family physicians, should be familiar with the presentation of 'fractured' penis, as prompt diagnosis and early surgical repair are instrumental in ensuring a successful outcome with minimal complications. The public should also be educated to seek medical attention immediately, as delay or failure to report may result in permanent physical and psychological disabilities that could otherwise have been avoided.

A newly developed compound derived by fermentation, isomaltooligosaccharide (IMO), was hypothesized to enrich cecal bifidobacterial populations and reduce colonization levels of Salmonella in the ceca of broiler chickens. Broiler starter diets were prepared with final IMO concentrations of 1% (wt/wt), 2% (wt/wt), and 4% (wt/wt) and a control diet without IMO supplementation. Chickens were divided into 4 groups and challenged with 10(8) cell of Salmonlella enterica ser. Typhimurium with 200 microg/mL nalidixic acid resistant (S. Typhimurium Nalr) after 7 d of placement. The experiment was done in 3 replications. IMO-supplemented diets resulted in significantly higher cecal bifidobacteria compared with the control diet (P < 0.05). However, there was no significant difference in bifidobacteria counts among the treatment groups. Chickens fed diets with 1% IMO had a significant 2-log reduction in the level of inoculated S. Typhimurium Nalr (P < 0.05) present in, the ceca compared with the control group, but no differences were found between the control group and the groups fed 2 or 4% IMO for S. Typhimurium Nalr. No differences in feed consumption, feed conversion, or feed efficiency compared with the control group were observed; however, the result showed a significant reduction in weight for birds fed 1% IMO diet compared with those fed the control diet.

Pheochromocytoma is a rare tumor of chromaffin cells that secrete catecholamines and several cytokines. The clinical manifestations are protean and may include hypertension, weight loss, sweating, palpitation, headache, anxiety, tremor, nausea, vomiting, and hypercalcemia. The tumor can mimic many unrelated diseases, leading to significant delay and difficulty in diagnosis. We report a case of a 37-yr-old male admitted with jaundice, dark urine, fever, and signs of a systemic inflammatory response. Abdominal computed tomography revealed a heterogeneously enhancing tumor between the pancreatic tail and left kidney. There was no evidence of obstruction to bile flow, neoplastic involvement of the liver or bile ducts, or infectious etiology. The tumor was removed and found to be a pheochromocytoma. Immunohistochemical analysis revealed the presence of interleukin-1beta in the tumor cells. After surgery, the jaundice resolved without further treatment, leading us to the conclusion that it was a paraneoplastic phenomenon possibly related to interleukin-1beta production. We suggest that occult pheochromocytoma should be added to the differential diagnosis of unexplained intrahepatic cholestasis.

The complex dietary carbohydrates, called prebiotics, have been used to control Salmonella and improve intestinal bacterial balance in broilers. Leuconostoc mesenteroides (ATCC 13146) isomaltooligosaccharides (IMO) stimulate growth of Bifidobacterium and Lactobacillus and are not used by Salmonella or Escherichia coli. We tested the efficacy of these IMO as a prebiotic. IMO, compared with fructooligosaccharides (FOS) as sole carbon source, promoted growth of chicken cecal isolates and Bifidobacterium. Cecal isolates and Salmonella typhimurium grown in mixed culture on IMO reduced the Salmonella population. Cecal isolates grown on IMO showed higher viable counts and faster growth than Salmonella, indicating a potential value for these oligomers for poultry intestinal microflora modification.

Radiotherapy is the treatment of choice for carcinoma of the uterine cervix. We report on a 62-year-old Chinese woman with cervical carcinoma, in whom a small bowel perforation developed 5 months after radiotherapy. Ten centimetres of small bowel, including the perforation site, were resected. No bowel adhesion was detected during the operation. The postoperative course was uneventful, and the patient was discharged home 7 days after surgery. Histological examination confirmed post-irradiation injury. The presenting complaints of patients with bowel perforation following radiotherapy vary, and signs of peritonitis may be absent. Emergency physicians must be alert for these complications in patients who have been treated with radiotherapy.

A case of subtle oesophageal perforation caused by a foreign body is described. A 48-year-old woman had had a chicken bone impacted in the upper oesophagus for 4 days. At presentation, the bone was dislodged at endoscopy, and two small round depressions at opposite sides of the oesophageal wall were visible. The chest X-ray findings were normal. Computed tomography of the thorax detected a small amount of air in the mediastinum. The water-soluble contrast swallow test showed no evidence of leakage. The patient was successfully treated using conservative measures.

A 43-year-old woman was taken to the accident and emergency department after a high-speed motor vehicle collision. She had only minor external injuries, but developed an episode of hypotension, which rapidly responded to fluid infusion. Chest X-ray showed a widened superior mediastinum. Computed tomography confirmed thoracic aortic injury. In patients with high-speed deceleration injury, even transient hypotension should be taken seriously and a diligent search for the source of bleeding should be immediately undertaken.

In children, neuroblastoma can mimic various orthopaedic pathologies and this may create difficulties for doctors in reaching the correct diagnosis. Stage IV neuroblastoma was initially diagnosed as transient synovitis in this case report of a 7-year-old girl presenting with hip and low back pain.

Murine (endemic) typhus is a notifiable disease in Hong Kong, but its diagnosis can be difficult. We report a case of murine typhus in a middle-aged man who presented with persistent fever, headache, and skin rash 2 weeks after returning from a visit to China. The diagnosis of murine typhus requires a high index of suspicion for a febrile patient with a history of potential exposure to the disease vector (rat flea) in an endemic area. The importance of early recognition lies in the potential for early therapeutic intervention, leading to decreases in morbidity and duration of stay in hospital.

A 39-year-old woman drank one tablespoon of white vinegar in order to 'soften' crab shell stuck in her throat. Endoscopy revealed inflammation of the oropharynx and second-degree caustic injury of the oesophagus extending to the cardia. She had an uneventful recovery. This case report confirmed that vinegar could cause ulcerative injury to the oropharynx and oesophagus. The folklore application of vinegar 'dislodging' a foreign body in the throat should be strongly discouraged.

To identify characteristics of patients who abscond from general hospital wards, and to determine patient outcomes.Retrospective study.In-patient wards of a public general hospital, Hong Kong.Incident reports of 116 absconding episodes over a 20-month period from 1 November 1998 to 30 June 2000 were reviewed. Clinical characteristics, time and reason for absconding, destination of patient, outcomes, and adverse events were recorded.The majority of patients who absconded were middle-aged males admitted through the Accident and Emergency Department to the specialty of general medicine. Most incidences occurred within 24 hours of admission while in the emergency admission wards. Twelve percent of incidents were repeated episodes of absconding. The most common clinical diagnoses given to this patient group were drug overdose, intoxication, and soft tissue injury. Known drug addicts (29.3%) formed a substantial proportion of the patient group. Forty- seven patients returned to the ward within a few hours, while a further nine (7.8%) re-attended the Accident and Emergency Department of the hospital within 4 days. Several adverse outcomes were recorded: one patient died following a fall from height and two patients committed criminal offences.Patient absconding incidents are an important issue in hospital risk management. They can delay the delivery of appropriate medical treatment and may lead to other adverse patient outcomes, in addition to potential medicolegal consequences.

To determine the prevalence of group A streptococcal infection and to evaluate the predictive value of clinical findings and rapid streptococcal antigen detection testing in patients presenting with a sore throat or suspected clinically to have acute pharyngitis.Prospective observational study.Accident and emergency department of a public hospital, Hong Kong.All patients presenting with a sore throat as the chief complaint, or suspected clinically to have acute pharyngitis, from April to September 2000.Demographic data, clinical features, microbiological throat culture results, and rapid streptococcal antigen detection (Accustrip) test results.Of 1449 patients recruited during the 6-month study period, only 44 (3.0%) had positive throat cultures for group A beta-haemolytic streptococcus. The majority of group A beta-haemolytic streptococci were isolated from patients between the age of 3 and 60 years. Clinical findings other than an absence of cough were found to be unhelpful in predicting group A beta-haemolytic streptococcal throat infection. The sensitivity of the rapid group A streptococcal antigen detection test was 52.6% and the specificity was 98.2%.The prevalence of group A beta-haemolytic streptococcus in patients presenting with a sore throat, or suspected clinically of having acute pharyngitis, was low. If empirical antibiotics were given to all such patients, 97% of them would be unnecessarily treated. Age and absence of cough were the only clinical findings helpful in predicting the presence of group A beta-haemolytic streptococcal throat infection. The rapid group A streptococcal antigen detection test can provide a quick guide to clinicians on the necessity of antibiotic therapy. However, a confirmatory throat culture backup is recommended for patients with a negative test result.

Deubiquitinating enzymes generate monomeric ubiquitin in protein degradation pathways and are known to be important for the early development in many organisms.RNA interference experiments targeted for a UBP homologue, UCH/CeUBP130, in C. elegans resulted in cell division defective embryos. Immunostaining localized UCH/CeUBP130 in the sperm and at the microtubule-organizing centre (MTOC) during early cleavage. Furthermore, the embryonic lethal phenotype was rescued by mating with wild-type males.Since it is known that the MTOC in the fertilized embryo is contributed by sperm asters in C. elegans, we suggest that UCH/CeUBP130 and ubiquitin protein degradation pathways may be involved in microtubule-based sperm aster formation. Therefore UCH/CeUBP130 is necessary for the formation of a functional MTOC in the fertilized embryo of C. elegans.

To present two clinical cases and demonstrate that occlusal trauma may affect healing of periapical pathoses.Two teeth with periradicular disease did not respond successfully to conventional root canal treatment or endodontic surgery. Occlusal adjustment was finally performed on both cases. After occlusal adjustment, uncomplicated healing and periapical repair occurred in both cases. The findings in these two cases suggest that occlusal trauma may play a role in the healing of periapical pathoses.Occlusal trauma is positively correlated with changes in periodontal tissues. Although experiments in animals have shown that application of forces to teeth will not induce further periodontal destruction, we believe that some failures of root canal treatment may be due to the presence of occlusal trauma modulating the responses of inflamed periapical tissues or apical pathoses with persistent infection.

Basic fibroblast growth factor (bFGF) and vascular endothelial cell growth factor (VEGF) were demonstrated to be important factors sustaining the growth of Kaposi's sarcoma. RF cells were used to provide a model to study the pathogenesis of Kaposi's sarcoma. In this paper, we demonstrated that bFGF is present in the RF cells, cultured media, and tissues from monkey. The biological activities of bFGF on RF cells were also studied in vitro with serum-free media. The bFGF from serum-free-conditioned media is biologically active to stimulate RF cells in certain media condition. The mitogenic effect was abrogated by sheep neutralizing anti-bFGF antibody. Furthermore, the effect of antibody was reversed by the addition of exogenous bFGF. ELISA measurements indicating the growth potency of conditioned media correlated with the amount of bFGF in the conditioned media. The data from flow cytometry demonstrated the co-existence of SRV-2 and bFGF among RF cells and RF tissues. Immunohistochemical staining of RF tissue blocks for bFGF revealed that bFGF was present in the tumor and the presence of bFGF was not caused by the artifact of tissue culture. These results indicate that bFGF is an important growth factor to promote RF cell growth in vitro and RF tumor in vivo. Further studies are required to determine the relationship between the interaction of bFGF, SRV-2, and VEGF. This model also provides an adequate alternative to the model induced by simian immunodeficiency virus (SIV) to study the Kaposi's sarcoma.

It has been reported in the literature that certain species of bacteria (periodontopathogens) present in the subgingival plaque are associated with destructive periodontal disease. The purpose of this study was to investigate and compare the presence and proportional distribution of periodontopathogens in the subgingival plaque of adult crowded versus non-crowded dental regions. Thirty adult patients with anterior dental crowding were selected from the Orthodontic Clinic of the University of Pennsylvania. After orthodontic records were taken and the periodontal examination was performed, subgingival plaque samples were collected from crowded (experimental) and contralateral non-crowded regions (control) of each patient. The presence of 9 periodontopathic species, Actinobacillus actinomycetemcomitans, Prevotella intermedia, Eikenella corrodens, Campylobacter rectus, Capnocytophaga species, Fusobacterium species, Peptostreptococcus micros, Porphyromonas gingivalis, and Bacteroides forsythus, was determined using culture and immunofluorescence techniques. The bacterial morphotype was also determined by the use of dark-field microscopy. It was found that supragingival plaque accumulation in crowded regions was significantly greater than in non-crowded regions. Analysis of the bacteria showed that the samples from crowded regions consistently contained more species of periodontopathogens than the samples from non-crowded regions. Morphologically, more spirochetes and motile rods were present in the crowded-region samples. In terms of the presence of individual periodontopathogens, Fusobacterium species, Capnocytophaga species, C rectus, and P micros were significantly more common in the crowded samples than in the non-crowded samples. It was concluded that: (1) more plaque accumulated in crowded areas; (2) more species of periodontopathogens were present in the subgingival plaque of crowded regions; (3) morphologically, more spirochetes and motile rods were present in crowded areas; and (4) Fusobacterium species, Capnocytophaga species, C rectus, and P micros were present more often in crowded areas than in non-crowded areas (P0.05).

A 49-year-old man presented with dysphagia and the sensation of a foreign body in the throat, after he had swallowed chicken meat that contained bones during the previous evening. There were no respiratory symptoms. A plain lateral soft-tissue X-ray of the neck and oesophagogastroduodenoscopy showed a grossly swollen epiglottis. His condition improved rapidly with intravenous antibiotic therapy. As acute epiglottitis may be a sudden life-threatening condition, a high index of suspicion should be maintained for patients who present with an obstructive sensation in the throat.

To compare the contributions of patients, emergency physicians, and surgeons in the delay of diagnosis and treatment of appendicitis, and the effects of delay on disease stage and complication rate.Retrospective study.Accident and emergency department of a district public hospital, Hong Kong.All patients undergoing emergency appendectomy between August 1998 to September 1999.Patient delay in presentation, emergency physician delay in hospital admission, and surgeon delay in performing the operation; operative findings; and postoperative complications.Of 158 patients undergoing emergency operation, 14 had no pathological diagnosis and four had a diagnosis other than that of acute appendicitis. Of the 140 pathologically confirmed cases of appendicitis, the mean emergency patient delay was greater in advanced appendicitis than it was in simple appendicitis (42.0 hours versus 24.9 hours; P0.005). The mean emergency physician delay in advanced appendicitis was also greater than it was in simple appendicitis (17.9 hours versus 5.8 hours; P0.05). The difference in the mean surgeon delay in simple (10.9 hours) and advanced (16.3 hours) appendicitis, however, was not significant. The mean emergency physician delay showed a significant association with the postoperative complication rate (P=0.05). The delay was mainly because of a failure to diagnose the condition and admit the patient at the first visit to the accident and emergency department (22.1%). The diagnostic accuracy showed a significant association with the level of experience of the emergency physician involved (P0.05).There should be a higher index of suspicion, better surgical training, and better senior supervision at accident and emergency departments, to avoid preventable morbidity and mortality in acute appendicitis.

A cDNA encoding an ubiquitin-specific processing protease, UBP109, in rat skeletal muscle was cloned and its product was characterized. Northern analysis revealed that UBP109 mRNA is highly expressed in testis and spleen, compared with other tissues. Furthermore, in situ hybridization showed that the level of UBP109 mRNA in liver, spinal cord and brain dramatically changed during embryonic development, indicating that the expression of UBP109 mRNA is developmentally regulated. UBP109 was expressed in Escherichia coli and purified to apparent homogeneity using a (125)I-labelled ubiquitin-peptide fusion as a substrate. The purified enzyme cleaved at the C-terminus of the ubiquitin moiety in natural and engineered fusions irrespective of their sizes. UBP109 also released free ubiquitin from poly-His-tagged penta-ubiquitin. Moreover, it released free ubiquitin from poly-ubiquitinated protein conjugates of rabbit reticulocytes. In addition, UBP109 localized to both the cytoplasm and the nucleus and, among three putative nuclear localization sequences, only the one located near the C-terminus is responsible for nuclear localization. These results suggest that UBP109 may play an important role in generation of free ubiquitin from its precursors and its recycling from poly-ubiquitinated protein conjugates, and hence in regulation of ubiquitin-mediated cellular processes, particularly related to embryonic development.

Insertion of a nasopharyngeal airway by nurses is considered to be invasive. We compared the incidence and severity of nasal injury associated with nasopharyngeal airway insertion by trained nurses to those by anesthesiologists to determine the safety of inserting a nasopharyngeal airway by nurses in cardiopulmonary resuscitation (CPR).One hundred and sixteen male and 96 female patients scheduled for general anesthesia were included in the study. The male and female patients were randomly assigned to two groups respectively. Anesthesia was induced with sodium thiopental and fentanyl intravenously. The patients were then ventilated with a bag-valve-mask by trained nurses or anesthesiologists. In the unsuccessfully ventilated patients, nasopharyngeal airways were inserted to facilitate subsequent ventilation. The nasopharyngeal airway, oropharynx, and nostrils were then examined. The incidence and severity of nasal trauma induced by trained nurses or by anesthesiologists were compared.The study revealed that nasopharyngeal airways applied by trained nurses did not induce more severe nasal trauma than those by anesthesiologists.We suggest that nasopharyngeal airways may be applied safely by trained nurses in CPR.