Long-Term Evaluation of Drivers' Behavioral Adaptation to an Adaptive Collision Avoidance System.

OBJECTIVE: Taking human factors approach in which the human is involved as a part of the system design and evaluation process, this paper aims to improve driving performance and safety impact of driver support systems in the long view of human-automation interaction. BACKGROUND: Adaptive automation in which the system implements the level of automation based on the situation, user capacity, and risk has proven effective in dynamic environments with wide variations of human workload over time. However, research has indicated that drivers may not efficiently deal with dynamically changing system configurations. Little effort has been made to support drivers' understanding of and behavioral adaptation to adaptive automation. METHOD: Using a within-subjects design, 42 participants completed a four-stage driving simulation experiment during which they had to gradually interact with an adaptive collision avoidance system while exposed to hazardous lane-change scenarios over 1 month. RESULTS: Compared to unsupported driving (stage i), although collisions have been significantly reduced when first experienced driving with the system (stage ii), improvements in drivers' trust in and understanding of the system and driving behavior have been achieved with more driver-system interaction and driver training during stages iii and iv. CONCLUSION: While designing systems that take into account human skills and abilities can go some way to improving their effectiveness, this alone is not sufficient. To maximize safety and system usability, it is also essential to ensure appropriate users' understanding and acceptance of the system. APPLICATION: These findings have important implications for the development of active safety systems and automated driving.

Revisiting human-machine trust: a replication study of Muir and Moray (1996) using a simulated pasteurizer plant task.

This study aimed to replicate Muir and Moray that demonstrated operators' trust in automated machines developing from faith, then dependability, and lastly predictability. Following the procedure of Muir and Moray, we asked undergraduate participants to complete a training program in a simulated pasteuriser plant and an experimental program including various errors in the pasteuriser. Results showed that the best predictor of overall trust was not faith but dependability, and that dependability consistently governed trust throughout the interaction with the pasteuriser. Thus, the obtained data patterns were inconsistent with those reported in Muir and Moray. We observed that operators in the current study used automatic control more frequently than manual control to successfully produce performance scores contrary to the operators in Muir and Moray. The results imply that dependability is a critical predictor of human-machine trust, which automation designer may focus on. More extensive future research using more modern automated technologies is necessary for understanding what factors control human-autonomy trust in modern ages. Practitioner Summary: The results suggest that dependability is a key factor that shapes human-machine trust across the time course of the trust development. This replication study suggests a new perspective for designing effective human-machine systems for untrained users who do not go through extensive training programs on automated systems.

Receptor-destroying enzyme (RDE) from Vibrio cholerae modulates IgE activity and reduces the initiation of anaphylaxis.

IgE plays a key role in allergies by binding to allergens and then sensitizing mast cells through the Fc receptor, resulting in the secretion of proinflammatory mediators. Therefore, IgE is a major target for managing allergies. Previous studies have reported that oligomannose on IgE can be a potential target to inhibit allergic responses. However, enzymes that can modulate IgE activity are not yet known. Here, we found that the commercial receptor-destroying enzyme (RDE) (II) from Vibrio cholerae culture fluid specifically modulates IgE, but not IgG, and prevents the initiation of anaphylaxis. RDE (II)-treated IgE cannot access its binding site on bone marrow-derived mast cells, resulting in reduced release of histamine and cytokines. We also noted that RDE (II)-treated IgE could not induce passive cutaneous anaphylaxis in mouse ears. Taken together, we concluded that RDE (II) modulates the IgE structure and renders it unable to mediate allergic responses. To reveal the mechanism by which RDE (II) interferes with IgE activity, we performed lectin microarray analysis to unravel the relationship between IgE modulation and glycosylation. We observed that RDE (II) treatment significantly reduced the binding of IgE to Lycopersicon esculentum lectin, which recognizes poly-N-acetylglucosamine and poly-N-acetyllactosamine. These results suggest that RDE (II) specifically modulates branched glycans on IgE, thereby interfering with its ability to induce allergic responses. Our findings may provide a basis for the development of drugs to inhibit IgE activity in allergies.

Human-Automation Trust to Technologies for Naïve Users Amidst and Following the COVID-19 Pandemic.

OBJECTIVE AND BACKGROUND: Trust is a critical factor that influences the success or failure of human-automation interaction in a variety of professional domains such as transportation, military, and healthcare. The unprecedented COVID-19 crisis will likely accelerate the implementation of automation and create unique problems involving human-automation trust for naïve users of automated technologies in the future. METHOD: We briefly review factors that can influence the development of human-automation trust amidst and following the COVID-19 pandemic. We focus on two theories on human-automation trust and how naïve users develop and maintain their trust in unfamiliar technologies. RESULTS: The current review identifies user workload and perceived risk as critical factors that will impact human-automation trust during the COVID-19 pandemic. Both theories predict that it is important for naïve users to accumulate and analyze behavioral evidence of automated technologies to maintain appropriate trust levels as the pandemic progresses. CONCLUSION AND APPLICATION: Theories of human-automation trust inform trajectories of trust development toward unfamiliar technologies for naïve users. In application, manufacturers and distributers should focus on communicating system information effectively to retain users who may be "forced" to use unfamiliar technologies during the COVID-19 pandemic.

Clinical outcome of definitive radiation therapy for superficial esophageal cancer.

OBJECTIVE: To analyze the clinical outcome of concurrent chemoradiotherapy in superficial esophageal cancer patients. METHODS: We retrospectively analyzed data for 123 patients with superficial esophageal cancer who received external beam radiotherapy without intracavitary brachytherapy plus systemic chemotherapy during 1998-2015. Elective nodal irradiation was not performed. The dosage to planning treatment volume was 60 Gy in 30 fractions. The main outcome measure was overall survival. RESULTS: Patient characteristics were as follows: median age, 66 (41-83) years; male/female ratio, 106/17; squamous cell carcinoma/other, 122/1; cT1a/cT1b, 27/96; cervical esophagus/upper thoracic esophagus/middle thoracic esophagus/lower thoracic esophagus, 7/9/66/41 and concurrent chemoradiotherapy/radiotherapy alone, 100/23. Cisplatin and 5-fluorouracil were the most commonly used agents (85%). At the last follow-up (median 60.5 months), 91 (74%) patients were alive. Complete response was achieved in 116 (94.4%) patients. The 5-year overall survival, progression-free survival and local control rates were 77.0, 46.9 and 62.7%, respectively, similar to that in the elderly patients (P = 0.878, 0.754 and 0.648, respectively). There were 55 failures: 42 local, 10 regional and 3 distant failures. Nine local and seven regional failures developed out-of-field. Thirty-eight local failures (90%) were successfully salvaged, of which 30 (71%) were salvaged via endoscopic removal; only 2 regional failures (20%) were salvaged. Fifteen G3 acute toxicities occurred. One pneumonitis (G3), one pneumothorax (G3) and two pericardial effusion (G2) were the late toxicities observed. There were no G4 toxicities or treatment-related deaths. CONCLUSIONS: Concurrent chemoradiotherapy without intracavitary brachytherapy was effective and safe for superficial esophageal cancer, even in elderly patients.

Effect of Dexmedetomidine on Mortality and Ventilator-Free Days in Patients Requiring Mechanical Ventilation With Sepsis: A Randomized Clinical Trial.

Importance: Dexmedetomidine provides sedation for patients undergoing ventilation; however, its effects on mortality and ventilator-free days have not been well studied among patients with sepsis. Objectives: To examine whether a sedation strategy with dexmedetomidine can improve clinical outcomes in patients with sepsis undergoing ventilation. Design, Setting, and Participants: Open-label, multicenter randomized clinical trial conducted at 8 intensive care units in Japan from February 2013 until January 2016 among 201 consecutive adult patients with sepsis requiring mechanical ventilation for at least 24 hours. Interventions: Patients were randomized to receive either sedation with dexmedetomidine (n = 100) or sedation without dexmedetomidine (control group; n = 101). Other agents used in both groups were fentanyl, propofol, and midazolam. Main Outcomes and Measures: The co-primary outcomes were mortality and ventilator-free days (over a 28-day duration). Sequential Organ Failure Assessment score (days 1, 2, 4, 6, 8), sedation control, occurrence of delirium and coma, intensive care unit stay duration, renal function, inflammation, and nutrition state were assessed as secondary outcomes. Results: Of the 203 screened patients, 201 were randomized. The mean age was 69 years (SD, 14 years); 63% were male. Mortality at 28 days was not significantly different in the dexmedetomidine group vs the control group (19 patients [22.8%] vs 28 patients [30.8%]; hazard ratio, 0.69; 95% CI, 0.38-1.22; P = .20). Ventilator-free days over 28 days were not significantly different between groups (dexmedetomidine group: median, 20 [interquartile range, 5-24] days; control group: median, 18 [interquartile range, 0.5-23] days; P = .20). The dexmedetomidine group had a significantly higher rate of well-controlled sedation during mechanical ventilation (range, 17%-58% vs 20%-39%; P = .01); other outcomes were not significantly different between groups. Adverse events occurred in 8 (8%) and 3 (3%) patients in the dexmedetomidine and control groups, respectively. Conclusions and Relevance: Among patients requiring mechanical ventilation, the use of dexmedetomidine compared with no dexmedetomidine did not result in statistically significant improvement in mortality or ventilator-free days. However, the study may have been underpowered for mortality, and additional research may be needed to evaluate this further. Trial Registration: clinicaltrials.gov Identifier: NCT01760967.

Comparative evaluation of Strongyloides ratti and S. stercoralis larval antigen for diagnosis of strongyloidiasis in an endemic area of opisthorchiasis.

The use of Strongyloides ratti as heterologous antigen for serodiagnosis of strongyloidiasis is preferable to Strongyloides from humans due to the ease and safety of antigen preparation. In Southeast Asia where Opisthorchis viverrini coexists with Strongyloides stercoralis, there has been no report in using S. ratti for serodiagnosis of S. stercoralis. In this study, performance of an enzyme-linked immunosorbent assay (ELISA) based on S. ratti was compared with that based on S. stercoralis for diagnosis of strongyloidiasis in areas where O. viverrini is co-endemic in Thailand. Of the 107 individuals, 50 (46.7 %) were positive for S. stercoralis by agar culture method and by ELISA; 82 (76.6 %) and 81 (75.7 %) were seropositive using S. ratti and S. stercoralis antigens, respectively. The levels of parasite-specific IgG to S. ratti and S. stercoralis antigen were significantly proportionally correlated (P < 0.001). Mixed infections with O. viverrini have little effect on diagnosis of strongyloidiasis. Of 42 subjects who were infected with other parasites, there were no cross-reaction with Angiostrongylus cantonensis, Taenia spp., hookworms, Paragonimus spp., Clonorchis sinensis, Ascaris lumbricoides except for Fasciola spp. (1 of 5), and Opisthorchis viverrini (5 of 20). In spite of cross-reactivities, the results suggest that the S. ratti antigen provides an useful option for diagnosis of strongyloidiasis in an endemic area of opisthorchiasis with high sensitivity comparable to the S. stercoralis antigen and provide a basis for effective control strategies for strongyloidiasis.

Design and evaluation of steering protection for avoiding collisions during a lane change.

This paper discusses the design of a driver assistance system for avoiding collisions with vehicles in blind spots. The following three types of support systems are compared: (1) a warning system that provides the driver with an auditory alert, (2) a 'soft' protection system that makes the steering wheel stiffer to tell the driver that a lane-change manoeuvre is not recommended and (3) a 'hard' protection system that cancels the driver's input and controls the tyre angle autonomously to prevent lane departure. The results of an experiment showed that the hard protection system was more effective for collision avoidance than either the warning or the soft protection system. The warning and soft protection systems were almost the same in terms of collision avoidance. The results suggest that the human-centred automation principle, which requires the human to have the final authority over the automation, can be violated depending on the context.

A real-time PCR for quantification of parasite burden and its correlations with clinical characteristics and anti-rKRP42 IgG level in cutaneous leishmaniasis in Sri Lanka.

In visceral and mucocutaneous leishmaniasis, humoral immune response can reflect disease severity and parasite burden. Cutaneous leishmaniasis (CL) in Sri Lanka is caused by a usually visceralizing parasite, Leishmania donovani. We assessed the parasite burden (relative quantity-RQ) in 190 CL patients using quantitative real-time PCR (qPCR-with primers designed for this study) and smear microscopy, then correlated it with clinical parameters and IgG response. RQ of parasite DNA was determined with human-specific glyceraldehyde 3-phosphate dehydrogenase (GAPDH) as the internal control. The qPCR sensitivity was tested with serially diluted DNA from cultured L. donovani parasites. Smears were assigned a score based on number of parasites per high power field. Data from previous studies were used for comparison and correlation; nested Internal Transcribed Spacer 1 (ITS1) PCR as reference standard (RS) and IgG antibody titers to the Leishmania rKRp42 antigen as the immune response. The qPCR amplified and quantified 86.8% of the samples while demonstrating a fair and significant agreement with ITS1-PCR and microscopy. Parasite burden by qPCR and microscopy were highly correlated (r = 0.76; p = 0.01) but showed no correlation with the IgG response (r = 0.056; p = 0.48). Corresponding mean RQs of IgG titers grouped by percentiles, showed no significant difference (p = 0.93). Mean RQ was higher in early lesions (p = 0.04), decreased with lesion size (p = 0.12) and slightly higher among papules, nodules and wet ulcers (p = 0.72). Our study established qPCR's efficacy in quantifying parasite burden in Sri Lankan CL lesions but no significant correlation was observed between the parasite burden and host IgG response to the Leishmania rKRP42 antigen.

Female pond frog vocalisation deters sexual coercion by males.

Avoiding sexual-conflict-induced sexual coercion is crucial for females, especially in anurans, where the necessity of sexual coercion counterstrategies is increased because of their strong male-male competition and external fertilisation. In this study, we tested the hypothesis that the recently discovered female Pelophylax nigromaculatus calls prevent male courtship and prevented sexual coercion. By observing the reproductive behaviour of anurans, this study examined when females emitted calls and how males responded to them, while comparing the reproductive conditions of call-emitting and non-call-emitting females. The results of this study revealed that females without eggs which were assumed to finish spawning emitted calls in response to male approaches, and the males subsequently moved away from the females obediently. This suggests that female P. nigromaculatus calls work as a counterstrategy against male sexual coercion. This countermeasure communication was first identified in anurans, suggesting that they engage in more complex bidirectional vocal communication during the breeding season than previously assumed.

Effects of brand and brand trust on initial trust in fully automated driving system.

Before Automated Driving Systems (ADS) with full driving automation (SAE Level 5) are placed into practical use, the issue of calibrating drivers' initial trust in Level 5 ADS to an appropriate degree to avoid inappropriate disuse or improper use should be resolved. This study aimed to identify the factors that affected drivers' initial trust in Level 5 ADS. We conducted two online surveys. Of these, one explored the effects of automobile brands and drivers' trust in automobile brands on drivers' initial trust in Level 5 ADS using a Structural Equation Model (SEM). The other identified drivers' cognitive structures regarding automobile brands using the Free Word Association Test (FWAT) and summarized the characteristics that resulted in higher initial trust among drivers in Level 5 ADS. The results showed that drivers' trust in automobile brands positively impacted their initial trust in Level 5 ADS, which showed invariance across gender and age. In addition, the degree of drivers' initial trust in Level 5 ADS was significantly different across different automobile brands. Furthermore, for automobile brands with higher trust in automobile brands and Level 5 ADS, drivers' cognitive structures were richer and varied, which included particular characteristics. These findings suggest the necessity of considering the influence of automobile brands on calibrating drivers' initial trust in driving automation.

Task difficulty, risk feeling, and safety margin in the determination of driver behavior to prepare for traffic conflicts.

Unpredictable pedestrian and cyclist behavior associated with their appearance on the road in blind spots contributes to traffic near-misses or crashes. When experienced drivers are confronted with uncertainty, they take defensive measures called hazard-anticipatory driving, such as decreasing the vehicle velocity and/or increasing the lateral distance. Our research sought to understand the motivational determinants and perceptual processes that determine driver behavior in preparation for traffic conflicts with covert hazards. This study aimed to investigate the influence of driving experience on drivers' perceptions and behaviors to prepare for traffic conflicts. Two experiments were designed with 8 experienced and 13 inexperienced participants. In Experiment 1, participants were asked to provide their subjective impressions of task difficulty, feeling of risk, and statistical risk pertaining to assess their perceptions of the separation between task demand and capability after viewing animation clips of road scenes with blind intersections under different forced speeds. In Experiment 2, participants drove using a driving simulator in scenes with blind intersections, similar to those in Experiment 1. We sought to explore the motivational determinants of behavior regarding the relationship between subjective feelings and objective safety margins. The results showed that the driver's perception of task difficulty correlated with their driving speed, and inexperienced participants tended to underestimate task difficulty compared to experienced participants. The task difficulty and the feeling of risk were strongly correlated regardless of experience, and estimation of statistical risk differed depending on experience. The subjective task difficulty (and/or risk feeling) and objective safety margin were strongly correlated for experienced participants. Experienced participants who perceived a higher degree of difficulty in the forced-paced driving task tended to have greater safety margins in the self-paced driving task. These findings suggest that experienced participants with individually tolerable safety margins adjust their driving velocity and/or lateral distance in the control of task difficulty (and/or risk feeling) to prepare for traffic conflicts. Therefore, the underestimation of task difficulty should be considered when designing effective measures, such as driver assistance systems, to guide inexperienced drivers toward normative behaviors.

The effect of risedronate (17.5 mg/week) treatment on quality of life in Japanese women with osteoporosis: a prospective observational study.

A prospective observational study to test the effects of risedronate 17.5 mg/week treatment on quality of life (QOL) of 1,363 Japanese female patients with osteoporosis showed QOL improvement after 12 weeks of administration. Comorbid factors such as ischemic heart disease, hip osteoarthritis, and higher values of FRAX blunted the effects of QOL of the treatment. Few studies have investigated the effect of osteoporosis treatment on QOL in relationship to comorbid factors other than osteoporosis and fracture. Efficacy was determined by changes over time in EQ-5D at baseline, at 12 and 24 weeks, and at the final assessment. Factors affecting changes in EQ-5D were evaluated with a multivariate analysis. Safety was determined by assessing the incident rate of adverse events. The improvement of EQ-5D compared to baseline was observed as significant after 12 weeks of treatment (p < 0.001). The greatest improvement was observed in the dimension of "pain/discomfort" by the multivariate analysis (p < 0.001). Factors affecting QOL improvement were FRAX value without BMD, age, glucocorticoid use, ischemic heart disease, hip osteoarthritis, and pain. The incidence rate of drug-related adverse events was 4.72 % (95 % confidence interval 3.63-6.02 %). Risedronate at 17.5 mg/week improved the QOL in patients with osteoporosis among Japanese women, and comorbidity factors decreased the effects.

Time-dependent power laws in the oxidation and corrosion of metals and alloys.

Using the equations which describe the oxide thickness as a function of the oxidation time and temperature in the thermal oxidation of Si, various experimental results on the oxidation and corrosion of metals and alloys available in the literature are analyzed. By the analyses, it is found that the weight loss of copper by atmospheric corrosion and the weight gains of austenitic stainless steel and Ni-Cr alloy by high temperature oxidation follow a time-dependent power law in which both diffusion and reaction are involved. It is also found that the pitting corrosion of aluminum alloys by the immersion with seawater and the high-temperature oxidation of Al(431) follow a time-dependent power law of a reaction-limited kind. In addition, an estimation is given of the activation energy for the pitting corrosion of mild steel by the immersion with seawater.

Design and evaluation of cooperative human-machine interface for changing lanes in conditional driving automation.

This study analyzes the impact of cooperative human-machine interface designs on drivers' trust in and interaction with automated driving systems (ADSs) during lane changes on highways. While drivers' inappropriate trust in ADSs can affect their behavior toward the system, capability to detect inadequate system performance, and perception of surrounding traffic disturbances, their engagement in the automated process can improve their comprehension of the system and traffic conditions, which is necessary for the safe practice of automated driving. Forty drivers practiced conditional driving automation in a driving simulator and encountered traffic congestion on the main lane of a two-lane highway. Four ADS designs were proposed to bypass the congestion. ADS-1 detects the congestion and synchronizes the speed accordingly. ADS-2 requests the driver to resume manual control and overtake the congestion. ADS-3 requests the driver to push a button to let the system overtakes the congestion automatically. ADS-4 overtakes the congestion automatically after informing the driver, while the driver can cancel it by pushing a button within 6 s. In all these conditions, driver intervention was optional. Although the drivers preferred and trusted ADS-1 and ADS-2 more than ADS-3 and ADS-4, the results indicate significant improvements in the driving performance and system usage under ADS-3 and ADS-4. Driving with ADS-3 improved drivers' engagement and reduced the requirement for control transfer compared with other systems. However, the time headway between the subject and adjacent vehicles indicated that lane changes were more critical under ADS-3 and ADS-4 than ADS-1 and ADS-2. Such deficiency of alignment between driver perception and safe behaviors has implications for the design of future studies and systems that need to balance satisfaction and safety. These observations are likely to improve driver interaction with automated vehicles.

Does automation trust evolve from a leap of faith? An analysis using a reprogrammed pasteurizer simulation task.

Trust is a critical factor that drives successful human-automation interaction in a myriad of modern professional environments. One seminal work on human-automation trust is Muir and Moray (1996) showing that human-machine trust evolves from faith, then dependability, and finally predictability in a simulated supervisory control task. However, our recent work failed to replicate the finding of the original study, calling for further replication efforts. Experiment 1 aimed to fully replicate Muir and Moray (1996) where participants performed a simulated pasteurizer task. Experiment 2 attempted to replicate Experiment 1 using participants who major in Engineering as used in the original study. Both experiments showed that dependability was the best initial predictor of trust, building later to predictability and faith. Two experiments consistently failed to support both the hypothesis proposed by Muir and Moray (1996), that trust develops from predictability to dependability to faith, and their original findings that trust develops initially from faith. The results of the current experiments challenge this widely cited view of how human-machine trust develops. Modern automation designers should be aware that dependability might control initial trust development for general users and incorporate dependability information into their designs.

Validation of an In-House ELISA Method in the Diagnosis of Cutaneous Leishmaniasis Caused by Leishmania donovani in Hambantota District, Sri Lanka.

Clinical diagnosis has become a challenge amidst a surge of cutaneous leishmaniasis in Southern Sri Lanka. The routine diagnostic method, slit-skin smear (SSS), has variable sensitivity, leading to undiagnosed cases. Improved diagnostics are urgently needed. We assessed a new in-house ELISA method for its diagnostic capabilities against ITS-1 nested PCR (gold standard­Gs). A cohort of 190 clinical CL cases was examined by SSS microscopy, anti-rKRP42 IgG ELISA (serum- and urine-based), and rK39-Immunochromatographic strip test. Validation was done using non-endemic sera, and cutoffs were developed using the receiver operating curve. The sensitivity of SSS for case detection was 77.9% (authors) and 76.3% (technicians). ELISA vs. Gs demonstrated sensitivity (Sn) = 94.4%; specificity (Sp) = 50.0%; positive predictive value (PPV) = 97.1%; negative predictive value (NPV) = 33.3%; Kappa agreement (Kp) = 0.39/p < 0.01. Comparison of the combination method (SSS by technicians and ELISA) vs. Gs showed: Sn = 98.9%; Sp = 30.0; PPV = 96.2; NPV 60.0%; Kp = 0.378/p < 0.01. All methods performed better compared to SSS (29.4%) where the clinical diagnosis was doubtful (PCR = 94.15%; serum ELISA = 88.2%; combination = 94.1%; p < 0.01 for all). High serum anti-rKRP42 titers were seen in those with multiple lesions. Anti-rKRP42 urine ELISA was suboptimal as a diagnostic test. A 9% rate of positivity was seen for rk39-ICT, and positives recorded high anti-rKRP42 titers. The diagnostic accuracy can be increased above the level of the Gs by combining SSS and ELISA. Advanced studies are required to understand the association between rk39-ICT positivity and high anti-rKRP42 titers.

Development of a Highly Sensitive Nested PCR and Its Application for the Diagnosis of Cutaneous Leishmaniasis in Sri Lanka.

The recent surge in cutaneous leishmaniasis (CL) in Sri Lanka has rendered clinical diagnosis difficult; thus, laboratory confirmation is indispensable. A modified (two novel inner primers to detect CL caused by Leishmania donovani) nested Internal Transcribed Spacer-1 (ITS1) PCR-Restriction Fragment Length Polymorphism (RFLP) method was developed and tested. The sensitivity of the modified nested PCR was tested using serial dilutions (103 to 10−2) of the DNA extract of a cultured L. donovani DD8 strain. Patients (n = 194) from Southern Sri Lanka were examined clinically, microscopically (Slit Skin Smear-SSS) and using the modified nested PCR. The modified nested PCR detected 2.55 fg of parasite DNA compared to ITS1 PCR (25 fg) and detected more cases than SSS (94.3% vs. 77.3%; p < 0.01). The RFLP pattern was L. donovani in all cases. The modified nested PCR performed well in clinically doubtful lesions (95% by PCR vs. 60% by SSS; p < 0.01), ulcerated nodules (91% vs. 71.8%; p < 0.01) and plaques (100% vs. 66.7%; p < 0.01). SSS demonstrated sensitivity (80.9%), specificity (81.8%), PPV (98.7%) and NPV (20.5%) against modified PCR. Low parasite loads and atypical lesions can be diagnosed by the proposed method with higher accuracy.

Comparison between gradient and spin-echo (GRASE) and compressed sensing sequences for single breath-hold three-dimensional magnetic resonance cholangiopancreatography in patients with T1 hyperintense bile.

PURPOSE: To compare image quality and the detectability of gallstones in patients with T1 hyperintense bile between single breath-hold three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP) with gradient and spin-echo (GRASE) and with compressed sensing (CS). METHODS: We retrospectively evaluated patients who underwent MRCP using GRASE and CS and had hyperintense bile on T1-weighted fat-suppressed images. The relative duct-to-periductal contrast ratios (RCs) of each bile duct segment were calculated. Pancreaticobiliary duct visibility, motion artifacts, background suppression, and overall image quality were scored on a 5-point scale. The Wilcoxon signed-rank test was used to analyze differences in qualitative and quantitative results. Diagnostic performance in detecting common bile duct (CBD) and gallbladder stones was assessed using receiver operating characteristic (ROC) curves. RESULTS: In total, 96 patients were included in the study. RCs of all bile duct segments in GRASE MRCP were significantly lower than those in CS MRCP (p < 0.001). All biliary duct visibility and overall image quality had significantly higher scores in GRASE MRCP than in CS MRCP (p < 0.001-0.003). Area under ROC curves of GRASE MRCP and CS MRCP were 1.00 and 0.88 for CBD stone (p = 0.14) and 0.93 and 0.82 for gallbladder stone (p = 0.08), respectively. CONCLUSIONS: GRASE MRCP provides better image quality than CS MRCP in patients with hyperintense bile on T1-weighted images. The detectability of biliary stones was also higher in GRASE MRCP than in CS MRCP, although not significantly.

Survey of domestic cattle for anti-Leishmania antibodies and Leishmania DNA in a visceral leishmaniasis endemic area of Bangladesh.

BACKGROUND: Visceral leishmaniasis (VL), caused by an intracellular parasite Leishmania donovani in the Indian subcontinent, is considered to be anthroponotic. The role of domestic animals in its transmission is still unclear. Although cattle are the preferred blood host for Phlebotomus argentipes, the sandfly vector of VL in the Indian subcontinent, very little information is available for their role in the disease transmission. In this study, we examined domestic cattle for serological and molecular evidence of Leishmania infection in a VL-endemic area in Bangladesh. Blood samples from 138 domestic cattle were collected from houses with active or recently-treated VL and post-kala-azar dermal leishmaniasis patients. The presence of anti-leishmanial antibodies in serum was investigated using enzyme-linked immunosorbent assay (ELISA) and then with direct agglutination tests (DAT). Nested PCR (Ln PCR) was performed to amplify the ssu-rRNA gene using the DNA extracted from Buffy coat. Recently-developed molecular assay loop-mediated isothermal amplification (LAMP) was also performed for further sensitive detection of parasite DNA. RESULTS: In this study, 9.4% (n=13) of the cattle were found to be positive by ELISA. Of the 13 ELISA-positive cattle, only four (30.8%) were positive in DAT. Parasite DNA was not detected in either of the molecular assays (Ln PCR and LAMP). CONCLUSIONS: The study confirmed the presence of antibodies against Leishmania parasite in cattle. However, the absence of Leishmania DNA in the cattle indicates clearly that the cattle do not play a role as reservoir host. Similar study needs to be undertaken in the Indian subcontinent to determine the role of other domestic animals on which sandflies feed.