Recent trend of pylephlebitis in Taiwan: Klebsiella pneumoniae liver abscess as an emerging etiology.

BACKGROUND AND AIMS: Pylephlebitis (septic thrombophlebitis of the portal venous system) is a rare complication of intra-abdominal infection. We aimed to investigate the recent trend of its etiology, clinical manifestation, and prognosis. METHODS: We retrospectively studied the etiology, clinical manifestation, and outcome by reviewing the medical records of all imaging-confirmed pylephlebitis cases diagnosed during the period 2002-2011 in a university hospital in Taiwan. To identify the risk factors for pylephlebitis, we randomly selected 160 patients with intra-abdominal infections but without pylephlebitis as the comparison group. RESULTS: We identified 35 cases of pylephlebitis. Most patients were men [29/35 (83 %)]. The median age of the patients was 57 years (range 35-90 years). Unspecified abdominal pain (18/35) and fever (10/35) were the most common clinical manifestations. Klebsiella pneumoniae liver abscess (7/35) and cholangitis (7/35) were the most common etiologies. Liver abscess was a risk factor for pylephlebitis (13/35 vs. 27/160, P = 0.01). With antibiotic therapy, there was no in-hospital mortality, but pylephlebitis was still associated with an excess hospital stay (22.2 ± 17.6 vs. 9.8 ± 7.1 days, P < 0.001). CONCLUSIONS: Our study results suggested a different pattern of pylephlebitis from previous Western literature. K. pneumoniae liver abscess (7/35) is an emerging etiology of pylephlebitis in Taiwan.

Optical and Mechanical Properties of New Ceramic CAD/CAM Materials.

OBJECTIVE: The purpose of this study was to compare the optical and mechanical properties of newer ceramic CAD/CAM materials to more established materials on the market. METHODS AND MATERIALS: The following ceramic materials were tested: lithium disilicate/lithium-aluminum silicate (Tessera, Dentsply/Sirona), lithium disilicate (Initial LiSi Block, GC), IPS e.max CAD, Ivoclar Vivadent), and 4Y polycrystalline stabilized zirconia (IPS e.max ZirCAD MT, Ivoclar Vivadent; Katana STML, Kuraray; YZ ST, VITA). Optical properties (translucency, opalescence) were determined using a dental spectrophotometer on 0.5-, 1.0-, 1.5-, or 2.0-mm specimens. Mechanical properties (flexural strength, flexural modulus, flexural fatigue strength, Weibull modulus, and characteristic strength) were determined with beams undergoing 3-point bend testing. The data were analyzed with multiple analyses of variance and Tukey's post hoc tests (α=0.05). RESULTS: Significant differences were found between groups based on type of ceramic or property (p<0.05). CONCLUSIONS: In general, the lithium disilicate based-ceramic materials had greater optical properties and lower mechanical properties than the zirconia-based ceramic materials.

Effect of Various Surface Treatments on Ti-Base Coping Retention.

CLINICAL RELEVANCE: Mechanical surface roughening of the titanium-abutment base is necessary to increase the pull-off bond strength of the lithium disilicate abutment material. Additional chemical surface treatment may further increase the bond strength, but the effects are product specific.

Properties of a New Nanofiber Restorative Composite.

A new nanofiber-reinforced hybrid composite (NovaPro Fill, Nanova) was recently introduced with reportedly improved mechanical properties. The purpose of this study was to compare the properties (flexural strength/modulus, degree of conversion [DC], depth of cure, and polymerization shrinkage) of the nanofiber composite to those of traditional hybrid composites (Filtek Z250, 3M ESPE; Esthet-X HD, Dentsply). To determine flexural strength and modulus, composite was placed in a rectangular mold, light-cured, stored for 24 hours, and then fractured in a universal testing machine. For degree of conversion, composite was placed in a cylindrical mold, light-cured, and stored for 24 hours. Measurements were made at the top and bottom surfaces using Fourier Transform Infrared Spectroscopy. To determine depth of cure, composite was placed in a cylindrical mold and light-cured. Uncured composite was scraped until polymerized resin was reached. Remaining composite was measured and divided by two. Polymerization shrinkage was determined by placing the composite material on a pedestal in a video-imaging device while light-curing. Shrinkage was determined after 10 minutes. Data were analyzed with one-way analysis of variance and Tukey post hoc test per property (α=0.05). Compared to Filtek Z250, NovaPro Fill had significantly lower flexural strength and modulus, greater volumetric shrinkage, and similar depth of cure, but greater top and bottom DC. Compared to Esthet-X HD, NovaPro Fill had similar flexural strength, shrinkage, and top and bottom DC, but significantly greater depth of cure and flexural modulus.

Redshift of edge emission from AlGaInP light-emitting diodes and correlation with electron-hole recombination lifetime.

The edge emission from AlGaInP light-emitting diodes showed a red-shifted peak in addition to the peak of surface emission. This shift resulted from the quantum-well absorption of the guided wave. Although the shift degrades the color quality and the extraction efficiency of the device, it helps elucidate many important optical properties of the material and the dynamics of carrier recombination, including the electron-hole recombination lifetime, the optical joint density of state, the spontaneous emission spectrum and the absorption spectrum. A simple concept of the bimolecular recombination is established. The corresponding coefficient can be expressed by a simple formula and was therefore determined.

Transgenic cloned mice expressing enhanced green fluorescent protein generated by activation stimuli combined with 6-dimethylaminopurine.

Most studies of mouse cloning successfully achieved activation of the reconstructed oocytes by strontium (Sr) combined with cytochalasin B (CB) treatment. A protein kinase inhibitor, 6-dimethylaminopurine (6-DMAP), was used to inhibit the activity of maturation promoting factor for activation of oocytes, but it has never been successfully applied in mouse cloning. This study investigates the activation efficiency of 6-DMAP in mouse somatic cell nuclear transfer (SCNT). Higher parthenogenetic blastocyst rates (71-72%, p < 0.05) were achieved in the oocytes treated with Sr6D (10 mM Sr combined with 2 mM 6-DMAP for 4 h) and Sr6D + SrCB (Sr6D for 2 h then Sr combined with 5 mug/ml CB for another 2 h), and a higher rate of hatching and hatched blastocyst was observed in the Sr6D + SrCB group (31%, p < 0.01) compared with other treatment groups (1-8%). For mouse cloning, cumulus cells of enhanced green fluorescent protein (EGFP)-expressed ESC chimera F1 were used as donor nuclei. Following activation, better development of the cloned embryos was observed in Sr6D + SrCB treatment. Moreover, different media, i.e. KSOM-AA, MEM-alpha and MK, for culturing cloned embryos were also compared in this study. Better morula/blastocyst (40%) and blastocyst (29%) rates were achieved in the embryos cultured in MEM-alpha medium (p < 0.05). Consequently, four EGFP cloned mice were generated in the activation treatment containing 6-DMAP following embryo transfer. In conclusion, treatment with 6-DMAP in combination with other activation stimuli successfully activates mouse reconstructed oocytes and support full-term development of the transgenic SCNT cloned embryos.

Global distribution of atrial ectopic foci triggering recurrence of atrial tachyarrhythmia after electrical cardioversion of long-standing atrial fibrillation: a bi-atrial basket mapping study.

OBJECTIVES: The objective of this study was to assess the spatial distribution of atrial ectopic foci potentially triggering recurrent atrial tachyarrhythmias after electrical cardioversion of long-standing atrial fibrillation (AF). BACKGROUND: It remains unknown whether targeted ablation of atrial ectopic foci concentrated in the pulmonary veins is feasible in patients with long-standin

Intravenous sotalol decreases transthoracic cardioversion energy requirement for chronic atrial fibrillation in humans: assessment of the electrophysiological effects by biatrial basket electrodes.

OBJECTIVES: This study was undertaken to assess the effects of sotalol on the transthoracic cardioversion energy requirement for chronic atrial fibrillation (AF) and on the atrial electrograms during AF recorded by two basket electrodes. BACKGROUND: The effects of sotalol infusion on transthoracic electrical cardioversion for chronic atrial fibrillation in humans have not been well investigated. METHODS: We included 18 patients with persistent AF for more than three months. Atrial electrograms were recorded by two basket electrodes positioned in each atrium respectively. Transthoracic cardioversion was performed before and after sotalol 1.5 mg/kg i.v. infusion. RESULTS: In the 14 patients whose AF could be terminated by cardioversion before sotalol infusion, the atrial defibrillation energy was significantly reduced after sotalol infusion (236 +/- 74 jules [J] vs. 186 +/- 77 J; p < 0.01). Atrial fibrillation was refractory to cardioversion in four patients at baseline and was converted to sinus rhythm by cardioversion after sotalol infusion in two of them. We further divided the patients into two groups. Group A consisted of 10 patients in whom the energy requirement was decreased by sotalol while group B consisted of eight patients in whom the energy requirement was not decreased. The mean A-A (atrial local electrogram) intervals during AF were significantly increased after sotalol infusion in both groups, but the increment of A-A interval was significantly larger in group A than it was in group B patients (36 +/- 13 ms vs. 22 +/- 8 ms for the right atrium; 19 +/- 7 ms vs. 9 +/- 7 ms for the left atrium; both p < 0.05). The spatial and temporal dispersions of A-A intervals were not significantly changed after sotalol infusion in both atria in both groups. CONCLUSIONS: Sotalol decreases the atrial defibrillation energy requirement by increasing atrial refractoriness but not by decreasing the dispersion of refractoriness.

Recovery of atrial function after atrial compartment operation for chronic atrial fibrillation in mitral valve disease.

OBJECTIVES: We prospectively studied the recovery of atrial function after atrial compartment operation and mitral valve surgery in patients with chronic atrial fibrillation caused by mitral valve disease. BACKGROUND: Chronic atrial fibrillation is the most common arrhythmia in mitral valve disease. This arrhythmia is associated with excessive morbidity and mortality. Mitral valve surgery alone rarely eliminates it. METHODS: Twenty-two patients underwent mitral valve surgery and a new surgical method, atrial compartment operation. Doppler echocardiography was performed in all patients before operation and at 1 week and 2 and 6 months after operation in the successful cardioversion group. Peak early diastolic (E) and atrial (A) filling velocities, peak A/E velocity ratio and A/E integral ratio of the mitral and tricuspid valves were measured. RESULTS: Sinus rhythm was restored immediately after operation in 91% of patients and was maintained for > 1 week in 15 (68%) of 22 patients and > 6 months in 14 (64%) of 22. Eleven of 15 patients had left atrial paralysis (A/E integral ratio 0) at 1 week and 6 of 14 patients at 2 months. Nine of 15 patients had right atrial paralysis (A/E integral ratio 0) at 1 week and 1 of 14 patients at 2 months. Both left and right atrial contractile function (presence of an A wave on Doppler findings) was detected at 6 months in 14 patients. Mean (+/- SD) peak atrial filling velocity of the mitral valve was 15 +/- 26 cm/s at 1 week, 38 +/- 39 cm/s at 2 months and 93 +/- 32 cm/s at 6 months (p < 0.001). Mean peak atrial filling velocity of the tricuspid valve was 14 +/- 19 cm/s at 1 week, 33 +/- 19 cm/s at 2 months and 50 +/- 19 cm/s at 6 months (p < 0.001). Peak early diastolic and atrial filling velocities, peak A/E velocity ratio and A/E integral ratio of the mitral and tricuspid valves increased significantly from 1 week to 6 months. CONCLUSIONS: Chronic atrial fibrillation in mitral valve disease can often be eliminated by atrial compartment operation. No surgical mortality or significant complications were encountered. Both left and right atrial function, as manifested by Doppler findings, recover after compartment operation and improve over time. The mechanical function of the right atrium recovers earlier than that of the left.

Clinical and electrophysiologic characteristics and long-term efficacy of slow-pathway catheter ablation in patients with spontaneous supraventricular tachycardia and dual atrioventricular node pathways without inducible tachycardia.

OBJECTIVES: We sought to investigate the long-term efficacy of slow-pathway catheter ablation in patients with spontaneous, documented paroxysmal supraventricular tachycardia (PSVT) and dual atrioventricular (AV) node pathways but without inducible tachycardia. BACKGROUND: The lack of reproduction of clinical PSVT by programmed electrical stimulation, which is not uncommon in AV node reentrant tachycardia (AVNRT), is a dilemma in making the decision of the therapeutic end point of radiofrequency catheter ablation. METHODS: Twenty-seven patients (group A) with documented but noninducible PSVT and with dual AV node pathways were prospectively studied. Programmed electrical stimulation could induce a single AV node echo beat in 12 patients, double echo beats in 4 patients and none in 11 patients at baseline or during isoproterenol infusion. Of the patients in group A, 16 underwent slow-pathway catheter ablation and 11 did not. The clinical and electrophysiologic characteristics of the 27 patients were compared with those of patients with dual AV node pathways and inducible AVNRT (group B, n = 55) and patients with dual AV node pathways alone without clinical PSVT (group C, n = 47). RESULTS: During 23+/-13 months of follow-up, none of the 16 patients with slow-pathway catheter ablation had recurrence of PSVT. However, 7 of the 11 patients without ablation had PSVT recurrence at 13+/-14 months of follow-up (p < 0.03 by Kaplan-Meier analysis). Compared with groups B and C, group A consisted predominantly of men who had better retrograde AV node conduction and a narrower zone for anterograde slow-pathway conduction. CONCLUSIONS: Slow-pathway catheter ablation is highly effective in eliminating spontaneous PSVT in which the tachycardia is not inducible despite the presence of dual AV node pathways.

Down-regulation of L-type calcium channel and sarcoplasmic reticular Ca(2+)-ATPase mRNA in human atrial fibrillation without significant change in the mRNA of ryanodine receptor, calsequestrin and phospholamban: an insight into the mechanism of atrial electrical remodeling.

OBJECTIVES: We investigated the gene expression of calcium-handling genes including L-type calcium channel, sarcoplasmic reticular calcium adenosine triphosphatase (Ca(2+)-ATPase), ryanodine receptor, calsequestrin and phospholamban in human atrial fibrillation. BACKGROUND: Recent studies have demonstrated that atrial electrical remodeling in atrial fibrillation is associated with intracellular calcium overload. However, the changes of calcium-handling proteins remain unclear. METHODS: A total of 34 patients undergoing open heart surgery were included. Atrial tissue was obtained from the right atrial free wall, right atrial appendage, left atrial free wall and left atrial appendage, respectively. The messenger ribonucleic acid (mRNA) amount of the genes was measured by reverse transcription-polymerase chain reaction and normalized to the mRNA levels of glyceraldehyde 3-phosphate dehydrogenase. RESULTS: The mRNA of L-type calcium channel and of Ca(2+)-ATPase was significantly decreased in patients with persistent atrial fibrillation for more than 3 months (0.36+/-0.26 vs. 0.90+/-0.88 for L-type calcium channel; 0.69+/-0.42 vs. 1.21+/-0.68 for Ca(2+)-ATPase; both p < 0.05, all data in arbitrary unit). We further demonstrated that there was no spatial dispersion of the gene expression among the four atrial tissue sampling sites. Age, gender and underlying cardiac disease had no significant effects on the gene expression. In contrast, the mRNA levels of ryanodine receptor, calsequestrin and phospholamban showed no significant change in atrial fibrillation. CONCLUSIONS: L-type calcium channel and the sarcoplasmic reticular Ca(2+)-ATPase gene were down-regulated in atrial fibrillation. These changes may be a consequence of, as well as a contributory factor for, atrial fibrillation.

Ring down artefacts on abdominal sonography to predict pulmonary abnormalities in the emergency department.

Ring down artefacts are sometimes found when emergency physicians perform abdominal ultrasound to differentiate between various abdominal problems. We describe a patient who presented with right upper quadrant abdominal pain and whose ultrasound examination showed ring down artefacts posterior to the right hemidiaphragm, which led to the eventual diagnosis of pneumonia. Ring down artefacts on ultrasound may be used to predict pulmonary abnormalities. Awareness of this sonographic finding may assist in accurate diagnosis and administration of appropriate treatment without delay.

A medical cost estimation with fuzzy neural network of acute hepatitis patients in emergency room.

Taiwan is an area where chronic hepatitis is endemic. Liver cancer is so common that it has been ranked first among cancer mortality rates since the early 1980s in Taiwan. Besides, liver cirrhosis and chronic liver diseases are the sixth or seventh in the causes of death. Therefore, as shown by the active research on hepatitis, it is not only a health threat, but also a huge medical cost for the government. The estimated total number of hepatitis B carriers in the general population aged more than 20 years old is 3,067,307. Thus, a case record review was conducted from all patients with diagnosis of acute hepatitis admitted to the Emergency Department (ED) of a well-known teaching-oriented hospital in Taipei. The cost of medical resource utilization is defined as the total medical fee. In this study, a fuzzy neural network is employed to develop the cost forecasting model. A total of 110 patients met the inclusion criteria. The computational results indicate that the FNN model can provide more accurate forecasts than the support vector regression (SVR) or artificial neural network (ANN). In addition, unlike SVR and ANN, FNN can also provide fuzzy IF-THEN rules for interpretation.

Determinants of Perceived Physical Environment Barriers among Community-Dwelling Elderly in Taiwan.

OBJECTIVES: To test the hypothesis that mobility, activities of daily living, and the interaction between them can play a key role in determining perceived physical environment barriers among community-dwelling elderly. DESIGN: Cross-sectional. SETTING: Community. PARTICIPANTS: One hundred and ninety-seven community-dwelling elderly with more than 7 points on the Short Portable Mental State Questionnaire and less than 7 points on the Geriatric Depression Scale (15 items). INTERVENTION: None. MEASUREMENTS: Time Get-up and Go test (TUG), the subscales of basic activity of daily living (BADL)/instrumental activities of daily living (IADL) of the Hierarchy of Care Required (HCR), and the physical/structural subscale of the Craig Hospital Inventory of Environmental Factors in Community-dwelling Elderly in Taiwan were used to measure mobility, activities of daily living and perceived physical environment barriers, respectively. Hierarchical linear regression analyses were used to test the study hypothesis. RESULTS: Significant and positive relations were found to exist between perceived physical environment barriers and (1) the TUG time (ß=.300, p<.05), and (2) the IADL score for the HCR (ß=.322, p<.05), respectively. A significant and negative relation existed between perceived physical environment barriers and the interaction term (the TUG time and the IADL score for the HCR) (ß=-.211, p<.05). CONCLUSION: Mobility, IADL and the interaction between them are found to be significant determinants of perceived physical environment barriers in the community-dwelling elderly under consideration. Strategies targeting the enhancement of mobility among community-dwelling elderly are suggested to lead to improvements in the degree to which physical environment barriers are perceived. This beneficial effect could be greater in the case of elderly individuals with better IADL function.

Importance of left atrial appendage function as a risk factor for systemic thromboembolism in patients with rheumatic mitral valve disease.

One hundred fifty-six patients with rheumatic mitral valve disease were studied with transesophageal echocardiography to assess the influence of left atrial (LA) appendage size and contractile function on the occurrence of systemic embolism. LA appendage function, represented by peak emptying velocity, was found to be a better indicator than LA spontaneous echo contrast as a risk factor for systemic thromboembolism.

Frequency of various congenital heart diseases in Chinese adults: analysis of 926 consecutive patients over 13 years of age.

A retrospective analysis was performed in 926 consecutive Chinese persons, aged 14 to 68 years, in whom congenital heart disease had been diagnosed and catheterization had been performed over the past 24 years. The incidence of various congenital cardiac malformations was compared with that in other series reported world-wide. About 60% of the 926 patients underwent surgery, and anatomic details of the malformations were examined. Congenital aortic valvular stenosis and coarctation of the aorta were uncommon (2.4% and 1.2%, respectively) among the Chinese adults, and the ethnic differences with Western countries in the incidence of these 2 defects were apparent and real. In contrast, aneurysm of the sinus of Valsalva, either ruptured or nonruptured, was more common (4.3%) and the incidence of outlet muscular type (or type 1) of ventricular septal defect was 4 to 9 times as common as has been reported in the West. Genetic differences rather than environmental factors or dietary habits may explain these special features.

Morphologic characterization and quantitative assessment of mitral regurgitation with ruptured chordae tendineae by transesophageal echocardiography.

To compare the accuracy of transesophageal echocardiography (TEE) with that of transthoracic echocardiography (TTE) in the detection of morphologic characteristics and in the quantitative assessment of the severity of mitral regurgitation with ruptured chordae tendineae, 40 patients with ruptured chordae tendineae (group 1) and 20 patients with moderate or severe mitral regurgitation due to other causes (group 2) were studied. All echocardiograms were recorded before cardiac surgery. Cardiac catheterization was performed in 55 patients (92%). TEE showed greater sensitivity and negative predictive value than TTE (100 vs 65%, and 100 vs 56%, respectively; p < 0.005) in the diagnosis of ruptured chordae tendineae. Visualization of the ruptured chordae (termed snake-tongue sign) was highly sensitive and specific (93 and 95%, respectively) for establishing the diagnosis of ruptured chordae tendineae. The severity of mitral regurgitation in group 1 patients evaluated by TTE color flow mapping was underestimated by 2 grades in 1 patient and by 1 grade in 6 patients, and overestimated by 1 grade in 1 patient, compared with left ventriculography. In contrast, by TEE color flow mapping it was underestimated by 1 grade in 1 and overestimated by 1 grade in 1 patient. TEE color flow mapping showed better correlation with angiography than did TTE color flow mapping (r = 0.82 vs r = 0.49).

Terminal cardiac electrical activity in adults who die without apparent cardiac disease.

Prolonged electrocardiographic (Holter) recording was performed to analyze terminal electrical events in 23 hospitalized adults who died without apparent cardiac disease. Most patients showed a gradual slowing of heart rate with shifting of cardiac pacemaker downward from the sinus node or atria to the atrioventricular junction and ventricles, resulting in cardiac asystole. Dominant bradyarrhythmia was more common than ventricular tachyarrhythmia (83 vs 17%). Agonal ST-segment elevation was not uncommon (26%). These terminal electrical events became manifest from 1 to 450 minutes (mean 62) before cessation of cardiac electrical activity. Forty-eight percent of the patients continued to show deteriorating sinus or atrial activity up to the last moment. The mechanism of bradycardiac asystole in patients with no apparent cardiac disease may be attributed to generalized anoxic and toxic depression of the sinus node and subsidiary pacemakers, together with neurogenic suppression of these structures.

Diagnostic accuracy of transesophageal echocardiography for detecting left atrial thrombi in patients with rheumatic heart disease having undergone mitral valve operations.

Transesophageal echocardiography (TEE) has emerged as an efficient method for detecting left atrial (LA) thrombi in recent years, but its accuracy has not been fully evaluated. A prospective clinicopathologic study in 213 consecutive patients with chronic rheumatic mitral valve disease over a period of 39 months was undertaken. All patients underwent open heart surgery within 3 days after the TEE study. The presence or absence of LA thrombi was confirmed at surgery by direct inspection of the left atrium and proven by histopathologic examination. Of the 213 patients, 147 had predominant mitral stenosis, and the remaining 66 patients had significant mitral regurgitation. Twenty-eight patients had LA thrombi by TEE criteria. These findings were all confirmed at surgicopathologic studies (specificity 100%). However, in 2 patients, LA thrombi were present but could not be detected by TEE (sensitivity 93.3%). Therefore, the positive predictive value was 100%, the negative predictive value was 98.9% and the diagnostic accuracy was 99.1%. No thrombi were found in patients with significant mitral regurgitation. The frequency of LA thrombi in patients with predominant mitral stenosis was 20% (30 of 147), and most of these patients had chronic atrial fibrillation (28 of 30, 93%). Only 16 patients (16 of 30, 53%) were found to have LA thrombi by transthoracic echocardiography. Furthermore, our data showed poor correlation between the echogenicity of LA thrombi and the degree of thrombus organization. Thus, TEE is excellent for detecting LA thrombi in patients with rheumatic heart disease severe enough to warrant mitral valve operations.