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Multimodality cardiac imaging of a left ventricular papillary fibroelastoma: a case report
No full textAbstract
Background
In the setting of an acute myocardial infarction (AMI), although the most common etiology of a left ventricular (LV) mass identified on multimodality cardiovascular imaging is a thrombus, other possibilities including a vegetation or tumor should be entertained within the differential diagnosis.
Case presentation
We describe a case of a 43-year-old Caucasian female post AMI diagnosed with a mid-cavitary mass within the LV. Although echocardiography and cardiovascular MRI (CMR) suggested that the mass was a thrombus, given the context of the recent AMI, exploration and surgical excision was completed by the surgeon due to the potential for the mass to embolize.
Conclusion
The final diagnosis of a papillary fibroelastoma was unique due to its unusual location and large size within the LV cavity. This unique case demonstrates shortcomings of multimodality cardiac imaging in the diagnosis of an atypical mass and the importance of obtaining tissue when clinically safe and feasible
A preliminary study of a novel emergency department nursing triage simulation for research applications
No full textAbstract
Background
Studying the effect on functioning of the emergency department of disasters with a potential impact on staff members themselves usually involves table top and simulated patient exercises. Computerized virtual reality simulations have the potential to configure a variety of scenarios to determine likely staff responses and how to address them without intensive utilization of resources. To decide whether such studies are justified, we determined whether a novel computer simulation has the potential to serve as a valid and reliable model of on essential function in a busy ED.
Methods
Ten experienced female ED triage nurses (mean age 51) mastered navigating a virtual reality model of triage of 4 patients in an ED with which they were familiar, after which they were presented in a testing session with triage of 6 patients whose cases were developed using the Emergency Severity Index to represent a range of severity and complexity. Attitudes toward the simulation, and perceived workload in the simulation and on the job, were assessed with questionnaires and the NASA task load index. Z-scores were calculated for data points reflecting subject actions, the time to perform them, patient prioritization according to severity, and the importance of the tasks. Data from questionnaires and scales were analyzed with descriptive statistics and paired t tests using SPSS v. 21. Microsoft Excel was used to compute a correlation matrix for all standardized variables and all simulation data.
Results
Nurses perceived their work on the simulation task to be equivalent to their workload on the job in all aspects except for physical exertion. Although they were able to work with written communications with the patients, verbal communication would have been preferable. Consistent with the workplace, variability in performance during triage reflected subject skill and experience and was correlated with comfort with the task. Time to perform triage corresponded to the time required in the ED and virtual patients were prioritized appropriately according to severity.
Conclusions
This computerized simulation appears to be a reasonable accurate proxy for ED triage. If future studies of this kind of simulation with a broader range of subjects that includes verbal communication between virtual patients and subjects and ..
Quantification of two isomeric flavones in rat colon tissue using reverse phase high performance liquid chromatography
No full textAbstract
Background
Antineoplastic activity has been previously shown for two isomeric flavones, 5,7-dihydroxy-3,6,8-trimethoxy flavone (flavone A) and 3,5-dihydroxy-6,7,8-trimethoxy flavone (flavone B), against colon cancer cell lines (Thomas et al. in PLoS ONE 7:e39806,
5
). Here, we present modified methods for the extraction and quantification of flavones A and B in rat colon tissue after intravenous dosing via high performance liquid chromatography, from the originally described procedure for extraction and quantification in rat plasma (Whitted et al. in J Chromatogr B Analyt Technol Biomed Life Sci 1001:150\u2013155,
7
).
Results
Modifications included tissue homogenization (1\ua0g tissue: 2\ua0mL water), filtration of the supernatant with a PVDF membrane, and the use of only one calibration curve to determine the concentration of each flavone in colon tissue. Good separation was achieved and representative equations were linear with r 2
\ua0\u2265\ua00.99 for both flavones. Precision and accuracy for flavone A ranged from 0.88\u201324.03 and 109\u2013116%. Precision and accuracy for flavone B ranged from 1.62\u201333.56 and 98\u2013113%. Concentrations of 1639\ua0\ub1\ua0601\ua0ng/g flavone A and 5975\ua0\ub1\ua02480\ua0ng/g of flavone B were detected in rat colon tissue 6\ua0h post dosing.
Conclusions
Modifications to the extraction methods for flavone A and flavone B from rat colon tissue\ua0had good separation, precision, and accuracy
Tau passive immunization inhibits not only tau but also A\u3b2 pathology
No full textAbstract
Background
Accumulation of hyperphosphorylated tau protein is a histopathological hallmark of Alzheimer\u2019s disease (AD) and related tauopathies. Currently, there is no effective treatment available for these progressive neurodegenerative diseases. In recent years, tau immunotherapy has shown great potential in animal models. We report the effect of immunization with tau antibodies 43D against tau 6\u201318 and 77E9 against tau 184\u2013195 on tau and amyloid-\u3b2 (A\u3b2) pathologies and cognition in triple-transgenic (3\ud7Tg)-AD mice at mild to moderate stages of the disease.
Methods
We immunized 12-month-old female 3\ud7Tg-AD mice with two to six or seven intravenous weekly doses of 15\ua0\u3bcg of mouse monoclonal antibody 43D, 77E9, a combination of one-half dose each of 43D and 77E9, or as control of mouse immunoglobulin G (IgG). Age-matched wild-type mice treated with mouse IgG or a mixture of 43D and 77E9 were also used as controls. The effect of immunization with tau antibodies on tau and A\u3b2 pathologies was assessed by Western blot and immunofluorescence analysis, and the effect on cognition was analyzed by using Morris water maze, one-trial novel object recognition, and novel object location tasks.
Results
We found that two doses of 43D and 77E9 reduced total tau but had no significant impact on hyperphosphorylation of tau. However, six doses of 43D reduced levels of both total tau and tau hyperphosphorylated at Ser262/356 and Ser396/404 sites in the hippocampus. Importantly, both 43D and 77E9 antibodies rescued spatial memory and short-term memory impairments in 3\ud7Tg-AD mice. The beneficial effect of 43D and 77E9 antibodies on cognitive performance was sustained up to 3\ua0months after the last dose. Six doses of immunization with 43D also decreased amyloid precursor protein (APP) level in CA1 and amyloid plaques in subiculum, and showed a trend toward reducing A\u3b240 and A\u3b242 in the forebrain. Immunization with 43D increased levels of complement components C1 and C9 and resulted in activation of microglia, especially surrounding A\u3b2 plaques.
Conclusions
These findings suggest the potential of passive immunization targeting proximal N-terminal domain tau 6\u201318 as a disease-modifying approach to AD and related tauopathies
Malignant transformation of a long-standing submental dermoid cyst to a carcinosarcoma: a case report
No full textAbstract
Background
Submental dermoid cysts are uncommon midline cysts which occur due to entrapment of ectoderm between the second and third branchial arches during embryogenesis. Most dermoid cysts of the head and neck are benign, but rarely malignant transformation may occur. To the best of our knowledge, this is the first report of a carcinosarcoma arising in a submental dermoid cyst.
Case presentation
A 42-year-old Sri Lankan Tamil man presented with a large cystic swelling in his submental region which was diagnosed as an extensive submental dermoid cyst. The cyst had been asymptomatic for 11 years but there was sudden enlargement and pain during the past 2 months. On surgical removal, a primary carcinosarcoma arising from part of the cyst wall was identified. After completion of radiotherapy, the disease was well controlled and he was disease free at 18 months.
Conclusions
Although extremely rare, a dermoid cyst of the submental region can undergo malignant transformation. It can be successfully treated with surgical excision and radiotherapy
Target parameter estimation for spatial and temporal formulations in MIMO radars using compressive sensing
No full textAbstract
Conventional algorithms used for parameter estimation in colocated multiple-input-multiple-output (MIMO) radars require the inversion of the covariance matrix of the received spatial samples. In these algorithms, the number of received snapshots should be at least equal to the size of the covariance matrix. For large size MIMO antenna arrays, the inversion of the covariance matrix becomes computationally very expensive. Compressive sensing (CS) algorithms which do not require the inversion of the complete covariance matrix can be used for parameter estimation with fewer number of received snapshots. In this work, it is shown that the spatial formulation is best suitable for large MIMO arrays when CS algorithms are used. A temporal formulation is proposed which fits the CS algorithms framework, especially for small size MIMO arrays. A recently proposed low-complexity CS algorithm named support agnostic Bayesian matching pursuit (SABMP) is used to estimate target parameters for both spatial and temporal formulations for the unknown number of targets. The simulation results show the advantage of SABMP algorithm utilizing low number of snapshots and better parameter estimation for both small and large number of antenna elements. Moreover, it is shown by simulations that SABMP is more effective than other existing algorithms at high signal-to-noise ratio
Some new lacunary statistical convergence with ideals
No full textAbstract
In this paper, the idea of lacunary
I
\u3bb
-statistical convergent sequence spaces is discussed which is defined by a Musielak-Orlicz function. We study relations between lacunary
I
\u3bb
-statistical convergence with lacunary
I
\u3bb
-summable sequences. Moreover, we study the
I
\u3bb
-lacunary statistical convergence in probabilistic normed space and discuss some topological properties
Effect of handrubbing using locally-manufactured alcohol-based handrubs in paediatric wards in Harare, Zimbabwe
No full textAbstract
We assessed bacterial contamination of hands of adults present in paediatric wards in two tertiary-care hospitals in Harare, Zimbabwe and the microbiologic efficacy of locally-manufactured alcohol-based hand rub (ABHR). During unannounced visits, samples were collected using hand-print and hand-rinse methods. Samples were collected from 152 individuals (16 nurses, 10 doctors, 28 students, 86 parents/guardians, 12 others). Contamination of hands with Gram-negative bacteria was found in 91% of adults tested with a mean of 14.6\ua0CFU (hand-rinse method; IQR 3\u201365), representing a high risk for transmission of pathogens potentially leading to nosocomial infections. A single application of ABHR under controlled conditions achieved an average of 82% (or 0.72 log) reduction in detectable counts. Amongst 49 Enterobacteriaceae isolates from hands, 53% were resistant to gentamicin and 63% were resistant to cefpodoxime. Use of ABHR represents an attractive intervention for reducing nosocomial infections in this setting
Integrating fisheries and agricultural programs for food security
No full textAbstract
Background
Despite the connections between terrestrial and marine/freshwater livelihood strategies that we see in coastal regions across the world, the contribution of wild fisheries and fish farming is seldom considered in analyses of the global food system and is consequently underrepresented in major food security and nutrition policy initiatives. Understanding the degree to which farmers also consume fish, and how fishers also grow crops, would help to inform more resilient food security interventions.
Results
By compiling a dataset for 123,730 households across 6781 sampling clusters in 12 highly food-insecure countries, we find that between 10 and 45% of the population relies on fish for a core part of their diet. In four of our sample countries, fish-reliant households are poorer than their counterparts. Five countries show the opposite result, with fish-reliant households having higher household asset wealth. We also find that in all but two countries, fish-reliant households depend on land for farming just as much as do households not reliant on fish.
Conclusions
These results highlight the need for food security interventions that combine terrestrial and marine/freshwater programming if we are going to be successful in building a more resilient food system for the world\u2019s most vulnerable people
Mutant HSPB1 causes loss of translational repression by binding to PCBP1, an RNA binding protein with a possible role in neurodegenerative disease
No full textAbstract
The small heat shock protein HSPB1 (Hsp27) is an ubiquitously expressed molecular chaperone able to regulate various cellular functions like actin dynamics, oxidative stress regulation and anti-apoptosis. So far disease causing mutations in HSPB1 have been associated with neurodegenerative diseases such as distal hereditary motor neuropathy, Charcot-Marie-Tooth disease and amyotrophic lateral sclerosis. Most mutations in HSPB1 target its highly conserved \u3b1-crystallin domain, while other mutations affect the C- or N-terminal regions or its promotor. Mutations inside the \u3b1-crystallin domain have been shown to enhance the chaperone activity of HSPB1 and increase the binding to client proteins. However, the HSPB1-P182L mutation, located outside and downstream of the \u3b1-crystallin domain, behaves differently. This specific HSPB1 mutation results in a severe neuropathy phenotype affecting exclusively the motor neurons of the peripheral nervous system. We identified that the HSPB1-P182L mutant protein has a specifically increased interaction with the RNA binding protein poly(C)binding protein 1 (PCBP1) and results in a reduction of its translational repressive activity. RNA immunoprecipitation followed by RNA sequencing on mouse brain lead to the identification of PCBP1 mRNA targets. These targets contain larger 3\u2032- and 5\u2032-UTRs than average and are enriched in an RNA motif consisting of the CTCCTCCTCCTCC consensus sequence. Interestingly, next to the clear presence of neuronal transcripts among the identified PCBP1 targets we identified known genes associated with hereditary peripheral neuropathies and hereditary spastic paraplegias. We therefore conclude that HSPB1 can mediate translational repression through interaction with an RNA binding protein further supporting its role in neurodegenerative disease