High-performance monolayer MoS2nanosheet GAA transistor

In this article, a 0.7 nm thick monolayer MoS2nanosheet gate-all-around field effect transistors (NS-GAAFETs) with conformal high-κmetal gate deposition are demonstrated. The device with 40 nm channel length exhibits a high on-state current density of ~410μAμm-1with a large on/off ratio of 6 × 108at drain voltage = 1 V. The extracted contact resistance is 0.48 ± 0.1 kΩμm in monolayer MoS2NS-GAAFETs, thereby showing the channel-dominated performance with the channel length scaling from 80 to 40 nm. The successful demonstration of device performance in this work verifies the integration potential of transition metal dichalcogenides for future logic transistor applications.

Comparison of Knot-Tying Techniques During the Arthroscopic Broström-Gould Procedure: Semiconstrained Freehand Versus Knot Pusher Techniques

Background

The arthroscopic Broström technique with or without Gould modification has been used to treat patients with anterior talofibular ligament injury who failed nonoperative management and progressed to chronic lateral ankle instability. However, some patients develop limited range of motion over the ankle joint postoperatively.

Purpose/Hypothesis

To compare the clinical outcomes and midterm functional performance of knot-tying techniques between using a knot pusher and a semiconstrained freehand tie during arthroscopic Broström-Gould procedure with inferior extensor retinaculum (IER) augmentation. It was hypothesized that the semiconstrained freehand tie would provide better plantarflexion of the ankle joint compared with the knot pusher.

Study Design

Cohort study; Level of evidence, 3.

Methods

Included were 135 consecutive patients with mild-to-moderate lateral ankle instability (mean age, 42.7 years; range, 16-78 years) who underwent an arthroscopic Broström-Gould procedure from March 1, 2016, to April 30, 2022. The patients were divided into 2 groups according to the tying technique used in the Gould modification: surgical tie using a knot pusher (KP group; n = 30) or a semiconstrained freehand tie (FT group; n = 105). Radiographic parameters and ultrasound dynamic testing were examined during the preoperative assessment. Preoperative and 2-year postoperative assessments comprised American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale, visual analog scale for pain, and 12-Item Short Form Survey (SF-12) scores.

Results

The 2 groups had no differences in age, sex, or severity distribution in the preoperative assessment. American Orthopaedic Foot and Ankle Society Ankle-Hindfoot Scale, visual analog scale pain, and SF-12 scores were significantly better at the postoperative evaluation (all P < .05) in both groups. No significant difference was noted between groups in outcome scores. In the KP group, however, 7 out of 30 patients (23.3%) developed ankle stiffness with tightness when performing plantarflexion movement. No patients in the FT group reported similar symptoms.

Conclusion

For mild-to-moderate chronic lateral ankle instability, we propose an arthroscopic Broström procedure with the addition of IER augmentation using a semiconstrained freehand tie to avoid overtightening the IER. This ensures favorable patient satisfaction and clinical outcomes without limitation of plantarflexion of the ankle joint and avoids the possible complication of stiffness with plantarflexion.

Midterm outcomes of midfoot and hindfoot arthrodesis with strut allograft for Müller-Weiss disease

Background

Müller–Weiss disease (MWD), a rare dysplastic disorder of the foot, is characterized by deformity, sclerosis, and fragmentation of the lateral part of navicular bone. Arthrodesis is the mainstay treatment for MWD. Generally, arthrodesis can be achieved through internal fixation with metallic implants, and morselized chip bone may be packed into the gap for better bone union. However, with this procedure, the original foot size is not maintained and support for the foot arch is not provided. Sequela of short foot, or flatfoot is commonly observed even though these complications of surgery had not been reported with cases of MWD treated by arthrodesis. Herein, we present a retrospective analysis of treating MWD through midfoot and hindfoot arthrodesis combined with strut allograft.

Methods

From August 2006 to June 2019, 20 patients with MWD (mean age, 59.6 years; range, 40–80 years) underwent midfoot and hindfoot arthrodesis with strut bone allograft and were followed for at least 24 months. The patients were able to ambulate and participate in rehabilitation programs 3 months postoperatively.

Results

The used four radiographic parameters (Meary’s angle in anteroposterior and lateral view, talonavicular coverage angle, calcaneal pitch) demonstrated significant differences (P < .05) preoperatively and postoperatively, but those between the postoperative values and the values at the last follow-up session did not, indicating that strut allograft was able to maintain normal alignment. The mean American Orthopaedic Foot & Ankle Society Ankle-Hindfoot scores at 2 years postoperatively revealed significant improvement from baseline, from 60.2 to 84.2 (P < .05). The 12-item Short Form Health Survey scores also improved significantly (P < .05). All patients reported substantial pain relief and exhibited improved functional outcomes and gait patterns.

Conclusions

For advanced-stage MWD, arthrodesis with a precisely shaped, size-matched strut allograft provided strong support for biomechanical alignment and enhanced functional performance.

Effects of whole body vibration on spinal proprioception in healthy individuals

BACKGROUND

Low back pain (LBP) is a common health problem with high reoccurrence rate. As patients with LBP are often found to be proprioception impaired, new proprioception exercises should be explored. Whole body vibration (WBV) has been proven to improve muscle function and proprioception.

OBJECTIVE

The aim of this study was to determine the effects of WBV on spinal proprioception when WBV was administered in standing and seated postures.

METHODS

Twenty healthy male individuals (mean age: 23.2±1.2 years) were recruited and randomly assigned to two WBV groups: WBV in standing or WBV in seated posture. Their body posture, lumbar repositioning ability, maximum reaching distance and lumbopelvic coordination during dynamic motion in flexion and extension were assessed before, immediately after, 30 minutes after and 1 hour after 5 minutes of WBV (18 Hz, 6 mm amplitude) exposure. A Mixed ANOVA was used to analyze the effects of group and time factors on these four outcome measures.

RESULTS

There were no significant interaction (group and time) and group effects on all outcome measures. Participants were found to have significant different time effect on body posture, lumbar repositioning ability, maximum reaching distance and lumbopelvic coordination.

CONCLUSIONS

WBV could significantly improve spinal proprioception including body posture, lumbar repositioning ability, maximum reaching distance and lumbopelvic coordination in healthy individuals. WBV protocol is recommended to confirm its clinical application for improving spinal proprioception and its effects on patients with LBP is warranted.

CXCR3-deficient mesenchymal stem cells fail to infiltrate into the nephritic kidney and do not ameliorate lupus symptoms in MRL. Faslpr mice

Mesenchymal stem cell therapy is a promising candidate for the treatment of systemic lupus erythematosus (SLE). To exert their efficacy fully, mesenchymal stem cells must infiltrate efficiently into the lesion sites. Here, we examined the role of CXCR3 in mesenchymal stem cell infiltration into the kidney of MRL. Fas^lpr mice, which highly expressed CXCL10. The phenotypes, production of immunosuppressive mediators, and capacity to inhibit T and B cells of CXCR3-deficient mesenchymal stem cells were similar to those of wild-type mesenchymal stem cells. However, they showed less infiltration into the nephritic kidney, less conjugation with endothelial cells and weaker MMP-9 expression than did wild-type mesenchymal stem cells. Consequently, CXCR3-deficient mesenchymal stem cells did not ameliorate lupus symptoms in MRL. Fas^lpr mice in comparison with wild-type mesenchymal stem cells. In summary, our data suggest that upregulation of CXCR3 in mesenchymal stem cells will be a good strategy to increase their infiltration into the kidney, which will improve therapeutic outcomes in SLE.

Using the chronic kidney disease guidelines to evaluate the renal safety of tenofovir disoproxil fumarate in hepatitis B patients

BACKGROUND

Renal dysfunction remains an issue in tenofovir disoproxil fumarate (TDF) for chronic hepatitis B (CHB) patients.

AIM

To evaluate renal safety of TDF according to the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

METHODS

We retrospectively recruited CHB patients who received either TDF or entecavir (ETV) monotherapy from January 2008 to August 2015. After excluding confounding conditions, 253 patients who received TDF were randomly matched 1:2 with 506 patients who received ETV through the propensity scores, which consisted of age, gender, cirrhosis, chronic kidney disease (CKD) and estimated glomerular filtration rate (eGFR). Renal function deterioration was defined as a drop in GFR category accompanied with a ≥25% eGFR decline. Cumulative incidences of and hazard ratios (HRs) for renal dysfunction were analysed.

RESULTS

The mean eGFR decline was significantly greater in the TDF group over 48 months (TDF vs ETV: 15.73 mL/min/1.73 m² , 95% confidence interval [CI]: 13.76-17.70 vs 5.96 mL/min/1.73 m² , 95% CI: 4.72-7.19; P < 0.001). The cumulative incidence of renal function deterioration was significantly higher in the TDF group (TDF vs ETV: 11.1%, 95% CI: 7.4-14.8 vs 1.7%, 95% CI: 1.0-2.4; P < 0.001). After adjusting for age, pre-existing CKD and diabetes, TDF was independently associated with an increased risk of renal function deterioration (HR 5.36, 95% CI: 2.16-13.35; P < 0.001). Pre-existing CKD (HR 6.71, 95% CI: 2.25-17.65), proteinuria (HR 3.39, 95% CI: 1.23-9.39), and haematuria (HR 4.25, 95% CI: 1.32-13.68) were also independent factors of renal dysfunction.

CONCLUSION

By following the KDIGO guidelines, we confirmed that TDF was associated with a higher risk of renal dysfunction as compared to ETV.

The unresolved problem of beta-2 microglobulin amyloid deposits in the intervertebral discs of long-term dialysis patients

BACKGROUND

Dialysis-related destructive spondyloarthropathy caused by beta-2 microglobulin (β2M) amyloid deposits in intervertebral discs is a major burden for patients undergoing long-term dialysis. This study aimed to quantify the presence of β2M amyloid deposits in the intervertebral disc tissue of such patients and analyze whether there was a significant correlation between β2M accumulation and the duration of dialysis.

METHODS

Two groups of patients who had undergone surgery for degenerative spinal pathologies were selected: the dialysis group (n = 29) with long-term dialysis and the control group (n = 10) with no renal impairment. Tissue sections were prepared from specimens of intervertebral disc tissue obtained during spinal surgery and analyzed via histological staining, including immunohistochemistry (IHC) and Congo red.

RESULTS

There was a statistically significant multifold increase of β2M expression in the disc tissue of long-term dialysis patients when compared to non-dialysis patients, as shown by both IHC (0.019 ± 0.023 μm² vs. 0.00020 ± 0.00033 μm², respectively; p = 0.012) and Congo red staining (0.027 ± 0.041 μm² vs. 9.240 × 10^-5 ± 5.261 × 10^-5 μm², respectively; p = 0.047). We also note a moderate strength positive correlation between the duration of dialysis and positive IHC (r = 0.39; p = 0.015) and Congo-red staining (r = 0.42; p = 0.007).

CONCLUSIONS

The problem of β2M amyloidosis in long-term dialysis patients remains unresolved even with predominant use of high-flux dialysis membranes. This highlights the insufficiency of current dialysis modalities to effectively filter β2M.

Blunt Abdominal Trauma with Left Kidney Dropped into Lower Retroperitoneal Cavity: A Case Report and Literature Review

Blunt abdominal injury with kidney laceration is not unusually seen in high-energy traffic accident. It can present with no symptoms and yet lead to fatal complications. High-grade lacerations of kidney (American Association for the Surgery of Trauma [AAST] grade IV to V) will show up with contrast extravasation and disrupted kidney/pelvicalyceal system morphology in computed tomography (CT). However, it is rare to see kidney dislocation from retroperitoneal space because of the presence of the Gerota's fascia. We present a case of a 16-year-old boy suffering from traffic accident with blunt truncal/abdominal injury. The contrast CT of abdomen revealed that his left kidney was dislocated from the original retroperitoneal space and sagged to the lower retroperitoneal cavity. We performed emergency left nephrectomy. He recovered well and there was no complication noted after the surgical intervention. We also review the literature of kidney laceration regarding diagnosis and treatment. (Hong Kong j.emerg.med. 2016;24:176-179)

Secondary polycythaemia in a Malay girl with homozygous Hb Tak

Hb Tak is one of more than 200 high affinity haemoglobin variants reported worldwide. It results from the insertion of two nucleotides (AC) at the termination codon, between codon 146 and codon 147 of the beta-globin gene [Beta 147 (+AC)]. Polycythaemia is the main clinical feature although affected carriers are usually asymptomatic and do not require intervention. Several case studies in this region have reported the co-inheritance of Hb Tak with Hb E, delta beta and beta thalassaemia with one case of homozygous Hb Tak in a Thai boy. In this case report, a cluster of haemoglobin Tak was found in a family of Malay ethnic origin. Cascade family screening was conducted while investigating a 4-year old girl who presented with symptomatic polycythaemia. She had 2 previous Hb analysis done, at 7-month and 2-year-old with the diagnosis of possible Hb Q Thailand and Homozygous Hb D, respectively. Both diagnosis did not fit her clinical presentations. She was plethoric, had reduced exercise tolerance as well as cardiomyopathy. Her parents were consanguineously married and later diagnosed as asymptomatic carriers of Hb Tak. Consequently, re-analysis of the girl's blood sample revealed a homozygous state of Hb Tak. In conclusion, high oxygen affinity haemoglobin like Hb Tak should be considered in the investigation of polycythaemic patients with abnormal Hb analyses. In this case, DNA analysis was crucial in determining the correct diagnosis.

Disruption of effective connectivity from the dorsolateral prefrontal cortex to the orbitofrontal cortex by negative emotional distraction in obsessive-compulsive disorder

BACKGROUND

Obsessive-compulsive disorder (OCD) has been associated with abnormal cognitive and emotional functions and these dysfunctions may be dependent on the disruption of dynamic interactions within neuronal circuits associated with emotion regulation. Although several studies have shown the aberrant cognitive-affective processing in OCD patients, little is known about how to characterize effective connectivity of the disrupted neural interactions. In the present study, we applied effective connectivity analysis using dynamic causal modeling to explore the disturbed neural interactions in OCD patients.

METHOD

A total of 20 patients and 21 matched healthy controls performed a delayed-response working memory task under emotional or non-emotional distraction while undergoing functional magnetic resonance imaging.

RESULTS

During the delay interval under negative emotional distraction, both groups showed similar patterns of activations in the amygdala. However, under negative emotional distraction, the dorsolateral prefrontal cortex (DLPFC) and the orbitofrontal cortex (OFC) exhibited significant differences between groups. Bayesian model averaging indicated that the connection from the DLPFC to the OFC was negatively modulated by negative emotional distraction in patients, when compared with healthy controls (p < 0.05, Bonferroni-corrected).

CONCLUSIONS

Exaggerated recruitment of the DLPFC may induce the reduction of top-down prefrontal control input over the OFC, leading to abnormal cortico-cortical interaction. This disrupted cortico-cortical interaction under negative emotional distraction may be responsible for dysfunctions of cognitive and emotional processing in OCD patients and may be a component of the pathophysiology associated with OCD.

A Longitudinal Study of Compensated Dating and Juvenile Prostitution Behaviors Among Adolescents in Hong Kong

STUDY OBJECTIVE

The purpose of this study was to examine longitudinal changes in compensated dating (CD) and juvenile prostitution (JP) behaviors and related psychosocial correlates among Hong Kong adolescents.

DESIGN, SETTING, AND PARTICIPANTS

In this study, adolescent CD and JP behaviors were examined in 3 waves (namely wave 2, 3, and 4) of a longitudinal study. At wave 2 (2010-2011), 3638 secondary 2 students (grade 8) from 28 schools participated in the study (mean age, 13.60 years; SD = 0.72). In the following 2 academic years (2011-2012 and 2012-2013), they were invited to respond to the same questionnaire. A total of 2921 students completed the questionnaire in 3 waves and their results were analyzed.

RESULTS

The number of CD cases was higher than JP cases. Although there was a decline in CD cases at wave 4, the number of JP cases increased at wave 4. Although there was some support for the influence of family intactness and positive youth development on CD and JP, the evidence was not strong. The effects of gender, economic disadvantage, and family functioning on CD and JP were not significant.

CONCLUSION

There was a decrease in CD but an increase in JP in the 3 waves of data. However, there was a fluctuation of CD over the years which made it difficult to identify a stable pattern. Some possible explanations for such a fluctuation and the related nonsignificant findings are proposed.

Cognitive functioning in obsessive-compulsive disorder: a meta-analysis

BACKGROUND

Substantial empirical evidence has indicated impairment in the cognitive functioning of patients with obsessive-compulsive disorder (OCD) despite inconsistencies. Although several confounding factors have been investigated to explain the conflicting results, the findings remain mixed. This study aimed to investigate cognitive dysfunction in patients with OCD using a meta-analytic approach.

METHOD

The PubMed database was searched between 1980 and October 2012, and reference lists of review papers were examined. A total of 221 studies were identified, of which 88 studies met inclusion criteria. Neuropsychological performance and demographic and clinical variables were extracted from each study.

RESULTS

Patients with OCD were significantly impaired in tasks that measured visuospatial memory, executive function, verbal memory and verbal fluency, whereas auditory attention was preserved in these individuals. The largest effect size was found in the ability to recall complex visual stimuli. Overall effect estimates were in the small to medium ranges for executive function, verbal memory and verbal fluency. The effects of potentially confounding factors including educational level, symptom severity, medication status and co-morbid disorders were not significant.

CONCLUSIONS

Patients with OCD appear to have wide-ranging cognitive deficits, although their impairment is not so large in general. The different test forms and methods of testing may have influenced the performance of patients with OCD, indicating the need to select carefully the test forms and methods of testing used in future research. The effects of various confounding variables on cognitive functioning need to be investigated further and to be controlled before a definite conclusion can be made.

Toward patient-tailored perfusion thresholds for prediction of stroke outcome

BACKGROUND AND PURPOSE

Multiple patient-specific clinical and radiologic parameters impact traditional perfusion thresholds used to classify/determine tissue outcome. We sought to determine whether modified baseline perfusion thresholds calculated by integrating baseline perfusion and clinical factors better predict tissue fate and clinical outcome.

MATERIALS AND METHODS

CTP within 4.5 hours of acute anterior circulation stroke onset and 5- to 7-day MR imaging were performed for 203 patients with stroke, divided into derivation (n = 114) and validation (n = 89) data bases. Affected regions were operationally classified as infarct and noninfarct according to baseline CTP and follow-up FLAIR imaging. Perfusion thresholds were derived for each of the infarct and noninfarct regions, without and with transformation by baseline clinical and radiologic variables by using a general linear mixed model. Performance of transformed and nontransformed perfusion thresholds for tissue fate and 90-day clinical outcome prediction was then tested in the derivation data base. Reproducibility of models was verified by using bootstrapping and validated in an independent cohort.

RESULTS

Perfusion threshold transformation by clinical and radiologic baseline parameters significantly improved tissue fate prediction for both gray matter and white matter (P < .001). Transformed thresholds improved the 90-day outcome prediction for CBF and time-to-maximum (P < .001). Transformed relative CBF and absolute time-to-maximum values demonstrated maximal GM and WM accuracies in the derivation and validation cohorts (relative CBF GM: 91%, 86%; WM: 86%, 83%; absolute time-to-maximum 88%, 79%, and 80%, 76% respectively).

CONCLUSIONS

Transformation of baseline perfusion parameters by patient-specific clinical and radiologic parameters significantly improves the accuracy of tissue fate and clinical outcome prediction.

Effects of whole body vibration on spinal proprioception in normal individuals

Low back pain (LBP) is a common health problem with high reoccurrence rate. While most LBP cases are classified as non-specific, patients in general often present impaired proprioception. Whole body vibration (WBV) has been proven to improve muscle function and proprioception in the lumbo-pelvic region. The aim of this study was to determine whether WBV would affect spinal proprioception. Eleven young normal individuals were recruited. Their body alignment, lumbar repositioning error and lumbo-pelvic coordination during dynamic motion were assessed before and after 5 minutes WBV (18 Hz, 6 mm amplitude). Assessments were conducted before, immediately after, 30 minutes after and 1 hour after WBV. Subjects were found to have improved lumbo-pelvic coordination and flexibility without any adverse effect on the neuromuscular system after WBV. However, WBV had no significant immediate effect on lumbar repositioning ability and body alignment. Future studies of the effects of different WBV protocols on LBP patients are recommended.

The efficacy of i-SCAN for detecting reflux esophagitis: a prospective randomized controlled trial

New imaging technologies have been applied in endoscopy to improve the detection and differentiation of subtle mucosal changes using a digital contrast method. Among them, i-SCAN technology is the most recently developed image-enhancing technology. We investigated whether i-SCAN could improve the detection rate of reflux esophagitis. Interobserver agreement between endoscopists was compared with conventional white light (WL) endoscopic examination. We performed a prospective randomized controlled trial. A consecutive series of 514 subjects that underwent an esophagogastroduodenoscopy for health inspection were enrolled and randomized into the i-SCAN group (n = 246) and WL group (n = 268). An esophagogastroduodenoscopy with video recording was used for detecting reflux esophagitis, and reflux esophagitis were categorized by the modified Los Angeles (LA) classification. The total number of reflux esophagitis identified by WL and i-SCAN was 58 (21.7%) and 74 (30.1%), respectively. The diagnostic yield of reflux esophagitis was significantly higher (P = 0.034) in the i-SCAN group (30.1%) as compared to the WL group (21.6%). Using the modified LA classification, the detection rate of minimal changes was significantly higher (P = 0.017) in the i-SCAN group (11.8%) as compared to the WL group (5.6%), but the detection rates of LA-A and LA-B were not significantly different between the two groups (P = 0.897 and P = 0.311, respectively). After comparison of the interobserver agreement using randomly selected video clips, the i-SCAN group showed better agreement than the WL group (Kappa value, 0.793 vs. 0.473). Compared to WL endoscopy, applying i-SCAN in daily practice can improve the diagnostic yield of reflux esophagitis by detecting more minimal changes in the squamo-columnar junction of the esophagus and can improve the interobserver agreement of the modified Los Angeles classification.

An assessment of three noncommercial DNA extraction methods from dried blood spots for beta-thalassaemia mutation identification

INTRODUCTION

Dried blood spots (DBS) are currently the recommended sample collection method for newborn screening programmes in America. Early diagnosis of beta-thalassaemia screening is essential as it provides an added advantage especially in sickle cell disease. Beta-thalassaemia frequency is high in many poor countries, and the cost of using commercial DNA extraction kits can be prohibitive. Our study assessed three methods that use minimal reagents and materials to extract DNA from DBS for beta-thalassaemia identification.

METHODS

The methods assessed in this study were Tris-EDTA (TE) buffer-based method by Bereczky et al. (American Journal of Tropical Medicine and Hygiene 72, 2005, 249), NaCL/NaOH/Sodium dodecyl sulphate (SDS) method by Huang et al. (Human Genetics 84, 1990, 129) and NaOH method by Zhou et al. (Analytical Biochemistry 354, 2006, 159). Extracted DNA was amplified for three common beta-thalassaemia mutations in Malaysia.

RESULTS

Amplicons derived from TE buffer-based method were very faint and almost nonexistent while the NaCl/NaOH/SDS method did not produce any visible amplicons. The extraction using NaOH method produced visible bands that were comparable to the standard method using extraction kit.

CONCLUSION

The NaOH method is a simple method that uses minimal equipment and reagents that make it labour- and cost-effective. This method could be adopted by poorer countries to extract DNA for beta-thalassaemia mutation characterization.

Early rate of contrast extravasation in patients with intracerebral hemorrhage

BACKGROUND AND PURPOSE

For patients with ICH, knowing the rate of CT contrast extravasation may provide insight into the pathophysiology of hematoma expansion. This study assessed whether the PCT-derived PS can measure different rates of CT contrast extravasation for admission CTA spot signs, PCCT, PCL, and regions without extravasation in patients with ICH.

MATERIALS AND METHODS

CT was performed at admission and at 24 hours for 16 patients with ICH with/without contrast extravasation seen on CTA and PCCT. PCT-PS was measured at admission. The Wilcoxon rank sum test with a Bonferroni correction was used to compare PS values from the following regions of interest: 1) spot sign lesions only (9 foci), 2) PCL lesions only (9 foci), 3) hematoma excluding extravasation, 4) regions contralateral to extravasation, 5) hematoma in patients without extravasation, and 6) an area contralateral to that in 5. Additionally, hematoma expansion was determined at 24 hours defined by NCCT.

RESULTS

PS was 6.5 ± 1.60 mL · min(-1) × (100 g)(-1), 0.95 ± 0.39 mL · min(-1) × (100 g)(-1), 0.12 ± 0.39 mL · min(-1) × (100 g)(-1), 0.26 ± 0.09 mL · min(-1) × (100 g)(-1), 0.38 ± 0.26 mL · min(-1) × (100 g)(-1), and 0.09 ± 0.32 mL · min(-1) × (100 g)(-1) for the following: 1) spot sign lesions only (9 foci), 2) PCL lesions only (9 foci), 3) hematoma excluding extravasation, 4) regions contralateral to extravasation, 5) hematoma in patients without extravasation, and 6) an area contralateral to that in 5. PS values from spot sign lesions and PCL lesions were significantly different from each other and all other regions, respectively (P < .05). Hematoma volume increased from 34.1 ± 41.0 mL to 40.2 ± 46.1 mL in extravasation-positive patients and decreased from 19.8 ± 31.8 mL to 17.4 ± 27.3 mL in extravasation-negative patients.

CONCLUSIONS

The PCT-PS parameter measures a higher rate of contrast extravasation for CTA spot sign lesions compared with PCL lesions and hematoma. Early extravasation was associated with hematoma expansion.

Comparison of transnasal small-caliber vs. peroral conventional esophagogastroduodenoscopy for evaluating varices in unsedated cirrhotic patients

BACKGROUND AND STUDY AIMS

We aimed to evaluate the accuracy of transnasal small-caliber esophagogastroduodenoscopy (TNSC-EGD) compared with peroral conventional EGD (POC-EGD) for evaluating varices in unsedated patients with liver cirrhosis. The success rate, safety, endoscopist satisfaction, and patient tolerability of TNSC-EGD were also addressed.

PATIENTS AND METHODS

One hundred patients with liver cirrhosis participated in this randomized crossover trial, and 84 subjects completed both procedures. Of the 84 patients, 28 had marked bleeding diathesis (platelet count ≤ 50000/mm (3) and/or prothrombin time ≥ 1.7 INR). Endoscopists and patients answered questionnaires using a 100-mm visual analog scale about, respectively, their satisfaction and their tolerance of the procedure.

RESULTS

The success rate of TNSC-EGD was comparable to that of POC-EGD (96% vs. 99%). Nasal mucosal hemorrhages induced by TNSC-EGD occurred in 5 patients (6%), but were easily controlled. Compared to the POC-EGD reference test, diagnostic accuracies of TNSC-EGD for detecting esophageal varices, gastric varices, and red color signs were 98%, 98%, and 96%, respectively. Concordance rates on grading esophageal varices and gastric varices were excellent at 93% (κ  =  0.85) and 96% (κ  = 0.87). Endoscopist satisfaction was not significantly different between TNSC-EGD and POC-EGD, whereas patient tolerance of TNSC-EGD was significantly greater than that of POC-EGD (79.0 ± 14.4 vs. 69.5 ± 16.1; P  = 0.001).

CONCLUSION

TNSC-EGD without sedation was found to be feasible, safe, and accurate for evaluating esophageal varices, gastric varices, and red color signs in patients with cirrhosis - even in those with marked bleeding diathesis. Furthermore, it was significantly better tolerated by patients, without altering endoscopist satisfaction. Our findings indicate that TNSC-EGD without sedation might be viewed as a potential alternative to POC-EGD for evaluation of varices.

An evolutionarily conserved nested gene pair - Mab21 and Lrba/Nbea in metazoan

The embedding of one gene in another as a nested gene pair is a unique phenomenon of gene clustering in the metazoan genome. A gene-centric paralogous genomic sequence comparison strategy was used in this study to align these paralogous nested pairs, Mab21l2-Lrba and Mab21l1-Nbea, to identify the associated paralogous non-coding elements (pNEs) they shared. A majority of these pNEs in the Mab21l2-Lrba locus display tissue-specific enhancer activities recapitulating the expression profiles of Mab21l2 and Mab21l1. Since these enhancers are spread into the introns of Lrba, dissociation of the two genes will likely disrupt the function of at least one of them. Phylogenetic analysis of this complex locus in different species suggests that Mab21 was probably locked in the Lrba/Nbea intron in the ancestral metazoan species, in which the cis-elements uncovered in this study may act as a selective force to prevent the dissociation of this gene pair in vertebrates.

Magnetism of FePt surface alloys

The complex correlation of structure and magnetism in highly coercive monoatomic FePt surface alloys is studied using scanning tunneling microscopy, x-ray magnetic circular dichroism, and ab initio theory. Depending on the specific lateral atomic coordination of Fe either hard magnetic properties comparable to that of bulk FePt or complex noncollinear magnetism due to Dzyaloshinski-Moriya interactions are observed. Our calculations confirm the subtle dependence of the magnetic anisotropy and spin alignment on the local coordination and suggest that 3D stacking of Fe and Pt layers in bulk L1_{0} magnets is not essential to achieve high-anisotropy values.

Nonlinear time series analysis of ground-level ozone dynamics in Southern Taiwan

The ozone pollution at ground level in rural and urban areas has been a long-standing problem in the world. This paper focuses on estimating self-affined nature of nonlinearity of ground-level peak ozone time series, which is analyzed by two nonlinear fractal statistical methods, including R/S analysis and BDS test. To explore the underlying structure of ozone observations at ground level and improve the forecasting capacity in urban region, practical implementation was assessed by a case study via collecting and analyzing the monitoring data at Chaojhou and Zenwu in the Kaohsiung metropolitan region, Taiwan. Based on R/S analysis, the time series can be identified as persistent and long-memory processes with Hurst exponents of both about 0.75. In addition, the V statistics specifies possible fluctuation cycle lengths of 32, 170, and 420 day simultaneously. Such results are consistent with the regional meteorological conditions leading to help characterize the regional scale ozone behavioral trend. Furthermore, the BDS test results confirm a strong nonlinearity of both time series associated with these two cities. Yet in both cases, nonlinearity implies chaos. The R/S analysis and BDS test provide strong evidence for nonlinearity and fractality of ozone time series due to noisy chaos, and we could not rule out the possibility of deterministic chaos in tropospheric ozone system.

Relationship between gamma-glutamyltransferase and metabolic syndrome in a Korean population

AIMS

To investigate associations between gamma-glutamyltransferase (GGT) and components of metabolic syndrome (MS), insulin resistance and inflammatory markers in the Korean population.

METHODS

The 3508 subjects enrolled in this survey participated in the Korean Rural Genomic Cohort (KRGC) study. Written consent was obtained from the local ethical committee. Of these participants, 1437 were men (mean age 56.9 +/- 7.9 years) and 2071 were women (mean age 55.8 +/- 8.1 years). We measured GGT levels and various biochemical markers. To examine insulin resistance status, we used the homeostasis assessment method for insulin resistance (HOMA-IR). For inflammatory marker, we used C-reactive protein (CRP) levels.

RESULTS

Serum GGT levels were significantly higher in the MS group compared to the healthy patient group [23 (5-1403) vs. 19 (5-1920) IU/l; P = 0.01]. The prevalence of MS and adjusted relative risk were both significantly increased from the lowest to highest GGT quartiles; these results persisted after adjustments for multiple confounders. Positive correlations were established between GGT and HOMA-IR or CRP.

CONCLUSION

These results suggest that GGT levels may be a surrogate marker of insulin resistance, inflammation and MS.

CT perfusion-derived mean transit time predicts early mortality and delayed vasospasm after experimental subarachnoid hemorrhage

BACKGROUND AND PURPOSE

There are limited indicators available to predict cerebral vasospasm in patients with subarachnoid hemorrhage (SAH). The purpose of this study was to determine if CT perfusion-derived hemodynamic parameters are predictors of vasospasm severity and outcome after experimental SAH.

MATERIALS AND METHODS

SAH was induced in 25 New Zealand white rabbits. Cerebral blood flow (CBF), cerebral blood volume (CBV), and mean transit time (MTT) were measured with CT perfusion before SAH, within 1 hour after SAH, and on days 2, 4, 7, 9, and 16 after SAH. Basilar artery diameter, measured with CT angiography and neurologic scoring, was also obtained on the same days. Differences between animals with moderate-severe delayed vasospasm (>/=24% basilar artery narrowing) and mild delayed vasospasm (<24% basilar artery narrowing) were investigated with repeated measures analysis of variance. Multiple linear regression analysis was used to investigate the relationship between CT perfusion parameters (CBF, CBV, MTT), basilar artery diameter, and neurologic score.

RESULTS

MTT increase <1 hour after SAH independently predicted mortality within 48 hours of SAH (P < .05). MTT and neurologic deficits were significantly greater with moderate-severe than with mild vasospasm (P < .05). MTT on day 2, but not CBF or CBV, was a significant predictor of subsequent moderate-severe delayed vasospasm (P < .05).

CONCLUSION

In the rabbit model of experimental SAH, the CT-derived hemodynamic parameter MTT on day 0 predicted early mortality, and MTT on day 2 predicted development of moderate-severe delayed vasospasm. MTT was also significantly correlated with arterial diameter and neurologic score.

Analysis of percutaneous transhepatic cholangioscopy-related complications and the risk factors for those complications

BACKGROUND AND STUDY AIMS

Percutaneous transhepatic cholangioscopy (PTC) is being increasingly used for patients with biliary tract diseases. The aim of this study was to assess the safety of this procedure, and we systematically analyzed PTC-related complications and the risk factors for those complications.

PATIENTS AND METHODS

A total of 364 patients who underwent PTC were included in the study. The initial diagnoses, the indications for PTC, the complications that occurred during the procedures, and the risk factors for these complications were retrospectively analyzed.

RESULTS

The overall incidence of complications was 12.9 % for percutaneous transhepatic biliary drainage (PTBD), 12.8 % for tract dilation, and 6.9 % for tract maturation. Complications developed in 58/848 PTC sessions (6.9 %). Cholangitis and bacteremia were associated with PTBD and tract dilation, catheter migration and blockage with tract maturation, and bile duct injury with PTC. Mild complications occurred in 80 patients (22.2 %) during the preparation stages and in 43 sessions (5.1 %) during the PTC itself. Severe complications, including severe hemobilia, hemoperitoneum, rupture of the sinus tract, and ductal injury developed in 17 patients (4.7 %) during the preparation period, and in 15 patients (4.1 %) during PTC. The overall incidence of severe complications along the entire course was 8.2 % (30/364 patients). No patient died or required surgery. Intraductal manipulations, such as electrohydraulic lithotripsy or balloon dilation, and the first session of PTC were risk factors for procedure-related complications.

CONCLUSIONS

PTC is a relatively safe and well-tolerated method for treating certain biliary tract diseases. Meticulous patient selection and a cooperative team approach are required in order to minimize the incidence of complications and to provide effective management.

Effects of tautomycetin on proliferation and fibronectin secretion in vascular smooth muscle cells and glomerular mesangial cells

Tautomycetin (TMC), a newly developed immunosuppressive agent, induces T-lymphocyte apoptosis through the inhibition of tyrosine kinase and protein phosphatase 1. We examined the effects of TMC on platelet-derived growth factor (PDGF)-induced proliferation and extracellular matrix synthesis in cultured vascular smooth muscle cells (VSMCs) and mesangial cells (MCs) of Sprague-Dawley rats, and investigated the molecular mechanisms involved. Different concentrations of TMC were administered 1 hour before the addition of 10 ng/mL PDGF into the growth-arrested and synchronized cells. Cell proliferation was assessed by methylthiazoletetrazolium (MTT) assay, fibronectin secretion, and the activation of Akt, ERK, and p38 MAPK by Western blot analysis. PDGF increased cell proliferation, fibronectin secretion, and the activation of Akt, ERK, and p38 MAPK in both VSMCs and MCs. In both cultured cells, TMC at >1 mug/mL significantly reduced basal MTT. TMC at 100 ng/mL significantly decreased the PDGF-induced VSMC and MC proliferation. However, fibronectin secretion and the activation of Akt, ERK, and p38 MAPK were not affected by this nontoxic concentration of TMC. The present data demonstrate that low-dose TMC reduced PDGF-induced VSMC and MC proliferation without affecting the fibronectin secretion and cellular kinase activation.

Hopelessness in Chinese adolescents in Hong Kong: demographic and family correlates

Chinese secondary school students (N = 3,017) responded to measures of adolescent hopelessness, perceived parental behavioral control (indexed by parental knowledge, expectation, monitoring, discipline, and demandingness, as well as Chinese parental control attributes), parental psychological control, and parent-child relational qualities (satisfaction with parental control, child's readiness to communicate with the parents and perceived mutual trust). Results showed that roughly one-fifth of Chinese adolescents displayed signs of hopelessness and adolescent hopelessness was related to adolescent age and gender as well as parental education and marital status. Although parental behavioral control was negatively related to adolescent hopelessness, parental psychological control was positively associated with adolescent hopelessness. Participants perceived parent-child relational qualities to be better showed lower levels of hopelessness.

Symptomatic giant Müllerian duct cyst in an infant: radiographic and CT findings

We report an unusual case of Müllerian duct cyst in an 8-month-old infant who presented with frequent vomiting and recurrent urinary tract infections. Computed tomography showed a midline giant cyst in the pelvic floor. Delayed enhanced computed tomography demonstrated contrast filling of the cyst, indicating a communication with the urotract. Subsequent cystourethrogram and surgery confirmed a giant Müllerian duct cyst.

Identity and conservation of mating type genes in geographically diverse isolates of Phaeosphaeria nodorum

Mating type idiomorphs (MAT1-1 and MAT1-2) were identified from the heterothallic loculoascomycete Phaeosphaeria nodorum (wheat biotype) using DNA from a pair of isolates from Poland and Georgia, USA that are known to mate. MAT predicted proteins of P. nodorum are similar in sequence and in phylogenetic relationship to those described for other loculoascomycetes such as Cochliobolus spp., Alternaria alternata, and Didymella zeae-maydis. The organization of the MAT locus of the P. nodorum differs from these species in that its idiomorph begins within an adjacent upstream conserved ORF of unknown function. MAT-specific primers were used to identify isolates of both mating types in field populations, demonstrating that an absence of either mating type is not the reason that the teleomorph has not been found in New York. Portions of MAT1-1 and MAT1-2 were sequenced from geographically diverse isolates, including those from regions where the teleomorph has been reported. MAT was highly conserved and no significant differences in sequence were found.

Effects of cryopreservation on meiotic spindles of oocytes and its dynamics after thawing: clinical implications in oocyte freezing--a review article

Embryo freezing has been a successful practice, but oocyte cryopreservation formerly achieved poorer results. This was mainly due to low rates of survival, fertilization, and development. The major dissimilarities for oocytes to embryos are the character of the plasma membrane, the presence of cortical granules, at the metaphase of meiosis II with the spindle system. In addition, the oocytes must be fertilized by sperm at the appropriate time. To improve the survival rate, a refined slow freezing method with increased sucrose concentration would dehydrate oocytes more sufficiently. Vitrification is another approach to prevent ice crystal formation. Intracytoplasmic sperm injection is used to overcome possible zona hardening from the release of cortical granules. The microtubules of meiotic spindles are vulnerable to the thermal changes and would depolymerize. Cryopreserved oocytes exhibited serious disturbances of the microtubules immediately after thawing. Fertilization of oocytes with disorganized spindles could lead to chromosomal aneuploidy, digyny, and arrest of cleavage. After incubation, the microtubules would repolymerize in a time-dependent way. Normal fertilization and development of cryopreserved oocytes improved after appropriate incubation and timing of insemination, compatible with recovery of the spindles. With the improvement of survival, fertilization, and cleavage, oocyte cryopreservation would gain an imperative role.

Studies of the central neural pathways to the stomach and Zusanli (ST36)

The purpose of this morphological study was to investigate the relation between the meridian, meridian points and viscera using neuroanatomical tracers. The common locations of the spinal cord and brain projecting to the stomach and Zusanli were observed following injection of CTB (cholera toxin B subunit) and pseudorabies viruses (PRV-Ba, Bartha strain and PRV-Ba-Gal, galactosidase insertion) into the stomach and Zusanli (ST36). After 4-5 days of survival following injection into twelve rats, they were perfused, and their spinal cords and brains were frozen sectioned (30 microm). These sections were stained by X-gal histochemical, CTB and PRV-Ba immunohistochemical staining methods, and examined with the light microscope. The results were as follows: Commonly labeled medulla oblongata regions were dorsal motor nucleus of vagus nerve (DMV), nucleus tractus solitarius (NTS) and area postrema (AP) following injection of CTB and PRV-Ba-Gal into stomach and Zusanli, respectively. In the spinal cord, commonly labeled neurons were found in thoracic, lumbar and sacral spinal segments. Densely labeled areas were found in lamina IV, V, VII (intermediolateral nucleus) and X of the spinal cord. In the brain, commonly labeled neurons were found in the Al noradrenalin cells/Cl adrenalin cells/caudoventrolateral reticular nucleus, dorsal motor nucleus of vagus nerve, nucleus tractus solitarius, area postrema, raphe obscurus nucleus, raphe pallidus nucleus, raphe magnus nucleus, gigantocellular nucleus, locus coeruleus, parabrachial nucleus, Kolliker-Fuse nucleus, A5 cell group, central gray matter, paraventricular hypothalamic nucleus, lateral hypothalamic nucleus, retrochiasmatic hypothalamic nucleus, bed nucleus of stria terminalis and amygdaloid nucleus. Thus central autonomic center project both to the stomach and Zusanli. These morphological results suggest that there is a commonality of CNS cell groups in brain controlling stomach (viscera) and Zusanli (limb).

Functional CT imaging of angiogenesis in rabbit VX2 soft-tissue tumour

Functional parameters such as blood flow (BF), microvessel permeability surface area product (PS), blood volume (BV) and mean transit time (MTT) are physiological markers related to the changes associated with angiogenesis. In the current study we present a functional CT technique for the simultaneous measurement of these four functional parameters and the display of each parameter as a functional image over an entire tissue slice. New Zealand White rabbits with implanted VX2 thigh tumours were scanned using CT with contrast media injection. The ex vivo method of radioactive microspheres was used to evaluate the accuracy of BF measurements with the functional CT technique. There was a significant linear correlation (R = 0.96) between regional CT and microsphere-measured BF values, with a slope not significantly different from unity (0.98 +/- 0.02, P < 0.0001). The precision of our CT technique was determined by the repeated scanning under steady-state conditions. The precision of CT-measured BF, PS. BV and MTT was 14%, 18%, 20% and 24%, respectively. In conclusion, BF can be measured accurately and BF, PS, BV and MTT reproducibly using our functional CT technique. Functional CT can be readily incorporated into existing imaging protocols to assess tumour angiogenesis.

Computer-aided prototype system for nose surgery

Rhinoplasty, or surgery to reshape the nose, is one of the most common of all plastic-surgery procedures. Rhinoplasty can enhance a patient's appearance and self-confidence, may also correct a birth defect or injury, or help relieve some breathing problem. In this paper, we present a three-dimensional (3-D) surgical simulation system, which can assist surgeons in planning rhinoplasty procedures. This system employs computer graphics and image-processing techniques for the simulation of a rhinoplasty. Although the presented algorithms themselves are not new, the proposed system exploits the new idea to apply 3-D morphing for rhinoplasty, and simulation results are useful for the physicians. According to patients' expectation of what they would like their noses to look like, our system simulates expected results. Our tools provide quantitative measurements of a nose structure. Using these quantitative results, surgeons can arrange appropriate preoperative plans for patients. Finally, experimental results and experiences are reported to evaluate the usefulness of the proposed system.

Single imaging modality evaluation of living donors in liver transplantation: magnetic resonance imaging

BACKGROUND

Liver graft size, anatomy of the bile duct and the vascular inflow and outflow are essential for living related liver transplantation (LRLT). Preoperative delineation of those variations that would change the operative procedure to achieve a successful result especially in an emergency condition.

PURPOSE

Our aim was to develop a rapid and noninvasive imaging diagnostic method for the detection of anatomical variants that is mandatory for a safe operation when selecting potential liver transplant living donors. We used a different magnetic resonance (MR) imaging technique, which enabled to us to exploit the anatomical landmark of the liver, signal enhancement of blood flow in the abdomen, and the intrahepatic biliary routes inside the liver. Then, with the help of Advantage Window workstation reconstruction, the reconstructed single vascular or biliary systems were displaced in a three-dimensional fashion and the whole examination finished within 30 min.

METHODS

Modification of the standard MR technique was performed on a superconductive 1.5T whole body image scanner, MR arteriogaphy, venography, and cholangiography with three-dimensional reconstruction in evaluating the anatomy of the hepatic arteries, hepatic veins, portal venous system, bile ducts, and liver size in potential liver transplant living donors. These anatomical structures were compared with traditional imaging methods.

RESULTS

In all 38 cases, as well as delineation of the portal vein detail to the segmental level was satisfactorily obtained in this MR study. The images were well displayed in a three-dimensional fashion, which had good correlation with images from traditional imaging modalities and operative findings. In 86.8% cases, the MR arteriography was well matched with the celiac angiography. Of those 17 operative cases, estimation of liver volume was well correlated with the liver graft within 3.9-12.5% variation. In the major hepatic vein, we obtained 100% accuracy and 88.2% in the minor branches. Of 12 donors received intraoperative cholangiography during liver donation, good correlation of biliary anatomy was achieved. One donor was excluded from graft donation due to the complicated arterial supply to the left liver. According to the anatomical variation, surgical procedures in graft harvesting and anastomosis were readjusted and no major complications were found in those donors and all recipients survived after liver transplantation.

CONCLUSION

MR volumetry, venography, angiography, and cholangiography with three-dimensional reconstruction is sufficient for all major imaging evaluation. It may replace the traditional conventional catheter angiography, computed tomography, sonography and endoscopic retrograde cholangiography as a single investigation in the evaluation of the potential liver transplant donors. Angiography is only valuable in suboptimal cases and intraoperative cholangiography is only performed in biliary ductile variants.

Direct DNA hybridization detection based on the oligonucleotide-functionalized conductive polymer

Electrochemical methods for DNA hybridization detection have many advantages that are very fast to detect hybridization and can be directly applied for a portable DNA sensor. In this paper, an electrochemical method to directly detect DNA hybridization was developed on the basis of a new conductive polymer, which was polymerized on the glassy carbon electrode with a terthiophene monomer having a carboxyl group (3'-carboxyl-5,2',5',2"-terthiophene). The ss-DNA probe was made by chemically bonding an amine-linked C6 alkyl group to the 5' terminus of oligonucleotide (19-mer). The probe moiety was immobilized on the polymer through covalent bonding with a catalyst, 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide. A difference in admittance was observed before and after hybridization as a result of the reduction of the resistance after hybridization. The highest difference in admittance was observed around 1 kHz before and after hybridization. Hybridization amounts of end two-base and center one-base mismatched sequences were obtained only in a 14.3% response when compared to that for the complementary matched sequence.