Degradation of pristine and oxidized single wall carbon nanotubes by CYP3A4

Carbon nanotubes (CNTs) are a class of carbon based nanomaterials which have attracted substantial attention in recent years as they exhibit outstanding physical, mechanical and optical properties. In the last decade many studies have emerged of the underlying mechanisms behind CNT toxicity including malignant transformation, the formation of granulomas, inflammatory responses, oxidative stress, DNA damage and mutation. In the present investigation, we studied the biodegradation of single-walled carbon nanotubes (SWCNTs) by Cytochrome P450 enzymes (CYP3A4) through using Raman spectroscopy. CYP3A4 is known isozyme accountable for metabolizing various endogenous and exogenous xenobiotics. CYP3A4 is expressed dominantly in the liver and other organs including the lungs. Our results suggest that CYP3A4 has a higher affinity for p-SWNTs compared to c-SWNTs. HEK293 cellular viability was not compromised when incubated with SWNT. However, CYP3A4 transfected HEK293 cell line showed no digestion of c-SWNTs after incubation for 96 h. Cellular uptake of c-SWNTs was observed by electron microscopy and localization of c-SWNTs was confirmed in endosomal vesicles and in the cytoplasm. This is the first study CYP3A4 degrading both p-SWNTs and c-SWNTs in an in vitro setup. Interestingly, our results show that CYP3A4 is more proficient in degrading p-SWNTs than c-SWNTs. We also employed computational modeling and docking assessments to develop a further understanding of the molecular interaction mechanism.

Development and validation of TaqMan real-time PCR for the detection of Burkholderia pseudomallei isolates from Malaysia

Rapid detection of Burkholderia pseudomallei, the etiologic agent of melioidosis, allows for timely initiation of appropriate treatment and better clinical outcomes. In the current gold standard, the culture method is time consuming and suffers from low sensitivity. Meanwhile, previously reported molecular assays are fast and sensitive, but their performance on isolates from Malaysia, an endemic region of melioidosis is under reported. This study designed oligonucleotides targeting orf2 of Type III secretion system (TTSS) genes cluster for the detection of Malaysian B. pseudomallei isolates and evaluated the assay on 95 local B. pseudomallei strains, 58 other microorganisms and 71 clinical specimens from patients. The developed assay exclusively detected all tested B. pseudomallei isolates with a detection limit of 20 fg per reaction (equivalent to ~2.5 copies). Subsequent testing on clinical samples showed that the assay detected all confirmed specimens with the growth of B. pseudomallei (n = 10/10). None of the negative specimens had a detectable signal of our TTSS-orf2 assay (n = 0/61). In conclusion, the present study provides crucial preliminary data for a subsequent study and should be considered as a potential alternative to current time-consuming culture method for the detection of B. pseudomallei.

New Routes for Novel Pyrazolo[3,4-b][1,6]-naphthyridine, Pyrazolo[3,4-b]pyridine and Pyrazolo[3,4:2,3]pyrido[6,1-a]benzimidazole Derivatives

Pyrazolo[3,4- b] [1,6] naphthyridine, pyrazolo[3,4- b] pyridine and pyrazolo[3,4:2,3] pyrido [6,1 -a] benzimidazole derivatives are synthesized starting from the isomeric 3-substituted 5-chloro-1-phenylpyrazole-4-carbaldehyde.

Facilitating patient-centered care: the development of illustrated multidimensional patient-reported outcome measures for children/adolescents with juvenile idiopathic arthritis

OBJECTIVES

To assess the validity, reliability, comprehensibility, and responsiveness to change of an illustrated child/parent multidimensional patient-reported outcome measures (PROMs) questionnaire which can assess construct outcome measures of children with juvenile inflammatory arthritis.

METHODS

A total of 122 children with juvenile idiopathic arthritis were included in this work in a multicenter study. The questionnaire included seven categories: (1) functional ability; (2) health-related quality of life; (3) disease activity measures: pain, global assessment, fatigue, and morning stiffness; (4) self-reported joint tenderness; (5) current medication, side effects, and adherence to therapy; (6) comorbidities; and (7) patient motivation. All the items were supported by illustrations to provide children with a visual impression of what was meant by the questions. The questionnaire has parent and patient versions. The disease activity status was assessed using JADAS-27.

RESULTS

The questionnaire was reliable as demonstrated by a high-standardized alpha (0.890-0.978). The questionnaire items correlated significantly (p < 0.01) with clinical parameters of disease activity. The patient-reported tender joints correlated significantly with the physician's scores (0.842). Changes in functional disability, quality of life, and the motivation score showed significant variation (p < 0.01) with disease activity status in response to therapy. The illustrated PROMs questionnaire showed also a high degree of comprehensibility (9.6).

CONCLUSIONS

Integrating PROMs into standard clinical practice is feasible and applicable. The illustrated questionnaire was valid and reliable. It provides an informative, quantitative measure for the disease activity score set data, and in the meantime, facilitates the assessment of the children's adherence to therapy, comorbidities, and motivation on an individual basis.

Cortical recruitment and functional dynamics in postural control adaptation and habituation during vibratory proprioceptive stimulation

OBJECTIVE

Maintaining upright posture is a complex task governed by the integration of afferent sensorimotor and visual information with compensatory neuromuscular reactions. The objective of the present work was to characterize the visual dependency and functional dynamics of cortical activation during postural control.

APPROACH

Proprioceptic vibratory stimulation of calf muscles at 85 Hz was performed to evoke postural perturbation in open-eye (OE) and closed-eye (CE) experimental trials, with pseudorandom binary stimulation phases divided into four segments of 16 stimuli. 64-channel EEG was recorded at 512 Hz, with perturbation epochs defined using bipolar electrodes placed proximal to each vibrator. Power spectra variation and linearity analysis was performed via fast Fourier transformation into six frequency bands (Δ, 0.5-3.5 Hz; θ, 3.5-7.5 Hz; α, 7.5-12.5 Hz; β, 12.5-30 Hz; [Formula: see text], 30-50 Hz; and [Formula: see text], 50-80 Hz). Finally, functional connectivity assessment was explored via network segregation and integration analyses.

MAIN RESULTS

Spectra variation showed waveform and vision-dependent activation within cortical regions specific to both postural adaptation and habituation. Generalized spectral variation yielded significant shifts from low to high frequencies in CE adaptation trials, with overall activity suppressed in habituation; OE trials showed the opposite phenomenon, with both adaptation and habituation yielding increases in spectral power. Finally, our analysis of functional dynamics reveals novel cortical networks implicated in postural control using EEG source-space brain networks. In particular, our reported significant increase in local θ connectivity may signify the planning of corrective steps and/or the analysis of falling consequences, while α band network integration results reflect an inhibition of error detection within the cingulate cortex, likely due to habituation.

SIGNIFICANCE

Our findings principally suggest that specific cortical waveforms are dependent upon the availability of visual feedback, and we furthermore present the first evidence that local and global brain networks undergo characteristic modification during postural control.

PI3K/Akt and Nrf2/HO-1 pathways involved in the hepatoprotective effect of verapamil against thioacetamide toxicity in rats

Liver is a precious organ to maintain body life. Hepatotoxicity is a worldwide health problem that is still a challenge for research. Although countless pharmaceutical drugs and herbal compounds were screened for their hepatoprotective effects, the death from hepatotoxicity is increasing. Thus, there is continuous necessity of searching for the hepatoprotective effect of commonly used drugs. Accordingly, our aim was to examine a hepatoprotective potential for the antihypertensive drug, verapamil, and searching for new insights underlie its protective mechanism. Four groups of adult male rats were randomly arranged as controls, thioacetamide (TAA) hepatotoxic, and TAA + verapamil treated. Serum liver enzyme, hepatic antioxidant, lipid peroxidation, and inflammatory parameters were assessed. Gene relative expression for heme oxygenase-1 (HO-1), nuclear factor-erythroid 2-related factor 2 (Nrf2), phosphoinositide 3-kinase (PI3K), and serine/threonine-specific protein kinase (Akt) were quantified in hepatic tissue. TAA caused hepatic injury evident both histopathologically and biochemically by a decrease in all gene expressions. Verapamil alleviated the injury via its antioxidant and anti-inflammatory effects that were suggested to be via upregulation of the previous gene expressions. In conclusion, the calcium channel blocker, verapamil, that is used widely as antihypertensive exhibits a valuable hepatoprotective effect. The protection partially rests on activation of Nrf2/HO-1 and PI3K/Akt pathways.

Perception and utilization of tetanus toxoid immunization among pregnant women attending a tertiary centre in North-West Nigeria

Background: Despite the availability of inexpensive and effective tetanus-toxoid-containing vaccines, elimination of maternal and neonatal tetanus worldwide has become a herculean task, particularly in low-income countries, due to poor immunization coverage. This study aimed to assess the perception and utilization of tetanus toxoid immunization among pregnant women attending a tertiary centre in North-West Nigeria. Materials and Methods: A cross-sectional study was conducted among 254 pregnant women (selected by systematic sampling technique) attending the antenatal clinic of Specialist Hospital, Sokoto, Nigeria. A structured interviewer-administered questionnaire was used to collect data on the research variables. Data were analyzed using IBM SPSS version 20 statistical computer software package. Results: Most, 221 (87.0%) of the 254 respondents had heard of tetanus toxoid immunization. Of these, only about half (51.1%) believed that it protects both mother and newborn baby from tetanus. Majority of respondents considered TT immunization to be effective in protecting against tetanus infection (73.3%) and also safe for both mother and baby (79.2%). About two-thirds of respondents (68.8%) had the misconception that a single dose of TT immunization protects from tetanus infection. Less than a quarter of respondents (23.6%) had received two or more doses of the vaccine. The main barriers to utilization of vaccines were lack of awareness of the vaccine (41.8%), not being aware of its benefits (36.7%), and fear of side effects (21.5%) Conclusion: Despite high levels of perception of the effectiveness and safety of TT immunization, the respondents in this study had low levels of perception and utilization of the protective doses of the vaccine. Government and healthcare workers should scale-up education of the populace on TT immunization schedule and implement community based vaccination of women of child bearing age in North-West Nigeria. Keywords: Perception, utilization, tetanus toxoid immunization, pregnant women

Finding Novel Anti-carcinomas Compounds by Targeting SFRP4 Through Molecular Modeling, Docking and Dynamic Simulation Studies

BACKGROUND

Secreted Frizzled-Related Protein 4 (SFRP4) is a glycoprotein that acts as a competitor of both canonical and non-canonical Wnt pathways. SFRP4 is mostly expressed in ovary and plays a significant role as a target molecule to cure ovarian carcinoma.

OBJECTIVE

Multiple chemical agonists are being used to cure ovary melanoma. We are interested in theoretically analyzing the compounds through computational approaches for their potential inhibitory effects against SFRP4.

METHODS

Compounds were sketched in Chemsketch drawing tool and minimized through chimera tool. Because the crystal structure of SFRP4 is not available in Protein Data Bank, homology modeling approach was used to predict Three-Dimensional (3D) crystal structure of SFRP4. Moreover, multiple computational approaches such as molecular docking and Molecular Dynamic (MD) simulations along with various online tools were employed to screen the best inhibitor against ovary melanoma.

RESULTS

The docking results showed that 1d and 1e compounds revealed significant binding energy values (-9.10 and -9.00 kcal/mol, respectively) compared with the standard drugs such as cis-platin and docetaxel (-3.30, -10.80 kcal/mol), respectively. Moreover, MD simulation results showed that 1d has little fluctuations throughout the simulation period as depicted by the root mean square deviation and root mean square fluctuation graphs.

CONCLUSION

The present in-silico study provides a deeper insight into the structural attributes of 1d compound and its overall molecular interactions against SFRP4 and gives a hypothetical gateway to use this compound as a potential inhibitor against ovarian carcinoma.

Dynamic reshaping of functional brain networks during visual object recognition

OBJECTIVE

Emerging evidence shows that the modular organization of the human brain allows for better and efficient cognitive performance. Many of these cognitive functions are very fast and occur in a sub-second time scale such as the visual object recognition.

APPROACH

Here, we investigate brain network modularity while controlling stimuli meaningfulness and measuring a participant's reaction time. We particularly raised two questions: i) does the dynamic brain network modularity change during the recognition of meaningful and meaningless visual images? And (ii) is there a correlation between network modularity and the reaction time of the participants? To tackle these issues, we collected dense-electroencephalography (EEG, 256 channels) data from 20 healthy human subjects performing a cognitive task consisting of naming meaningful (tools, animals…) and meaningless (scrambled) images. Functional brain networks in both categories were estimated at the sub-second time scale using the EEG source connectivity method. By using multislice modularity algorithms, we tracked the reconfiguration of functional networks during the recognition of both meaningful and meaningless images.

MAIN RESULTS

Results showed a difference in the module's characteristics of both conditions in term of integration (interactions between modules) and occurrence (probability on average of any two brain regions to fall in the same module during the task). Integration and occurrence were greater for meaningless than for meaningful images. Our findings revealed also that the occurrence within the right frontal regions and the left occipito-temporal can help to predict the ability of the brain to rapidly recognize and name visual stimuli.

SIGNIFICANCE

We speculate that these observations are applicable not only to other fast cognitive functions but also to detect fast disconnections that can occur in some brain disorders.

Identification of epileptogenic networks from dense EEG: A model-based study

Epilepsy is a network disease. Identifying the epileptogenic networks from noninvasive recordings is a challenging issue. In this context, M/EEG source connectivity is a promising tool to identify brain networks with high temporal and spatial resolution. In this paper, we analyze the impact of the two main factors that intervene in EEG source connectivity processing: i) the algorithm used to solve the EEG inverse problem and ii) the method used to measure the functional connectivity. We evaluate three inverse solutions algorithms (dSPM, wMNE and cMEM) and three connectivity measures (r(2), h(2) and MI) on data simulated from a combined biophysical/physiological model able to generate realistic interictal epileptic spikes reflected in scalp EEG. The performance criterion used here is the similarity between the network identified by each of the inverse/connectivity combination and the original network used in the source model. Results show that the choice of the combination has a high impact on the identified network. Results suggest also that nonlinear methods (nonlinear correlation coefficient and mutual information) for measuring the connectivity are more efficient than the linear one (the cross correlation coefficient). The dSPM as inverse solution shows the lowest performance compared to cMEM and wMNE.

Classification of pregnancy and labor contractions using a graph theory based analysis

In this paper, we propose a new framework to characterize the electrohysterographic (EHG) signals recorded during pregnancy and labor. The approach is based on the analysis of the propagation of the uterine electrical activity. The processing pipeline includes i) the estimation of the statistical dependencies between the different recorded EHG signals, ii) the characterization of the obtained connectivity matrices using network measures and iii) the use of these measures in clinical application: the classification between pregnancy and labor. Due to its robustness to volume conductor, we used the imaginary part of coherence in order to produce the connectivity matrix which is then transformed into a graph. We evaluate the performance of several graph measures. We also compare the results with the parameter mostly used in the literature: the peak frequency combined with the propagation velocity (PV +PF). Our results show that the use of the network measures is a promising tool to classify labor and pregnancy contractions with a small superiority of the graph strength over PV+PF.

Correlation of Troponin-I Level with Left Ventricular Ejection Fraction and In-hospital outcomes after First Attack of Non-ST Segment Elevation Myocardial Infarction

Coronary heart disease (CHD) is the most common cause of heart disease and is the single most important cause of premature death in developed world. Recognizing a patient with ACS is important because the diagnosis triggers both triage and management. cTnI is 100% tissue-specific for the myocardium and it has been shown to be a very sensitive and specific marker for acute myocardial infarction (AMI). Ventricular function is the best predictor of death after an acute coronary syndrome. It serves as a marker of myocardial damage, provides information on systolic function as well as diagnosis and prognosis. The study aimed at investigating the impact of elevated Troponin-I level on LV ejection fraction and in-hospital outcomes in patients with first attack of Non ST-segment Elevation Myocardial Infarction (NSTEMI). This prospective analytical study was conducted in the Department of Cardiology in Mymensingh Medical College Hospital from December 2015 to November 2016. Total 130 first attack of NSTEMI patients were included considering inclusion and exclusion criteria. The sample population was divided into two groups: Group I - Patients with first attack of NSTEMI with good LV function (LVEF: ≥55%). Group II - Patients with first attack of NSTEMI with LV systolic dysfunction (LVEF: <55%). Then Troponin-I and LVEF levels were correlated using Pearson's correlation coefficient test. In this study mean Troponin-I of Group I and Group II were 5.53±7.43 and 16.46±15.79ng/ml respectively. It was statistically significant (p<0.05). Echocardiography showed that patients with high Troponin-I level had low ejection fraction (LVEF) and patients with low Troponin-I level had preserved ejection fraction (LVEF). Analysis showed that patients with severe left ventricular systolic dysfunction (LVEF <35%) had the highest level of Troponin-I with worse in-hospital outcomes and vice versa-the patients with the preserved systolic function (LVEF ≥55%) had the lowest levels of Troponin-I with better in-hospital outcomes. In our study, it also showed that the levels of Troponin-I had negative correlation with LV ejection fraction levels, with medium strength of association (r= -0.5394, p=0.001). The study enabled us to conclude that, the higher was the Troponin-I level, the lower was the LV ejection fraction level and thus worse in-hospital outcomes in first attack of NSTEMI patients.

A predictive model of inflammatory markers and patient-reported symptoms for cachexia in newly diagnosed pancreatic cancer patients

BACKGROUND

Cachexia is a frequent manifestation of pancreatic cancer, can limit a patient's ability to take chemotherapy, and is associated with shortened survival. We developed a model to predict the early onset of cachexia in advanced pancreatic cancer patients.

METHODS

Patients with newly diagnosed, untreated metastatic or locally advanced pancreatic cancer were included. Serum cytokines were drawn prior to therapy. Patient symptoms were recorded using the M.D. Anderson Symptom Inventory (MDASI). Our primary endpoint was either 10% weight loss or death within 60 days of the start of therapy.

RESULTS

Twenty-seven of 89 patients met the primary endpoint (either having lost 10% of body weight or having died within 60 days of the start of treatment). In a univariate analysis, smoking, history symptoms of pain and difficulty swallowing, high levels of MK, CXCL-16, IL-6, TNF-a, and low IL-1b all correlated with this endpoint. We used recursive partition to fit a regression tree model, selecting four of 26 variables (CXCL-16, IL-1b, pain, swallowing difficulty) as important in predicting cachexia. From these, a model of two cytokines (CXCL-16 > 5.135 ng/ml and IL-1b < 0.08 ng/ml) demonstrated a better sensitivity and specificity for this outcome (0.70 and 0.86, respectively) than any individual cytokine or tumor marker.

CONCLUSIONS

Cachexia is frequent in pancreatic cancer; one in three patients met our endpoint of 10% weight loss or death within 60 days. Inflammatory cytokines are better than conventional tumor markers at predicting this outcome. Recursive partitioning analysis suggests that a model of CXCL-16 and IL-1B may offer a better ability than individual cytokines to predict this outcome.

A node-wise analysis of the uterine muscle networks for pregnancy monitoring

The recent past years have seen a noticeable increase of interest in the correlation analysis of electrohysterographic (EHG) signals in the perspective of improving the pregnancy monitoring. Here we propose a new approach based on the functional connectivity between multichannel (4×4 matrix) EHG signals recorded from the women's abdomen. The proposed pipeline includes i) the computation of the statistical couplings between the multichannel EHG signals, ii) the characterization of the connectivity matrices, computed by using the imaginary part of the coherence, based on the graph-theory analysis and iii) the use of these measures for pregnancy monitoring. The method was evaluated on a dataset of EHGs, in order to track the correlation between EHGs collected by each electrode of the matrix (called `node-wise' analysis) and follow their evolution along weeks before labor. Results showed that the strength of each node significantly increases from pregnancy to labor. Electrodes located on the median vertical axis of the uterus seemed to be the more discriminant. We speculate that the network-based analysis can be a very promising tool to improve pregnancy monitoring.

Functional connectivity disruptions correlate with cognitive phenotypes in Parkinson's disease

Cognitive deficits in Parkinson's disease are thought to be related to altered functional brain connectivity. To date, cognitive-related changes in Parkinson's disease have never been explored with dense-EEG with the aim of establishing a relationship between the degree of cognitive impairment, on the one hand, and alterations in the functional connectivity of brain networks, on the other hand.

This study was aimed at identifying altered brain networks associated with cognitive phenotypes in Parkinson's disease using dense-EEG data recorded during rest with eyes closed. Three groups of Parkinson's disease patients (N = 124) with different cognitive phenotypes coming from a data-driven cluster analysis, were studied: G1) cognitively intact patients (63), G2) patients with mild cognitive deficits (46) and G3) patients with severe cognitive deficits (15). Functional brain networks were identified using a dense-EEG source connectivity method. Pairwise functional connectivity was computed for 68 brain regions in different EEG frequency bands. Network statistics were assessed at both global (network topology) and local (inter-regional connections) level.

Results revealed progressive disruptions in functional connectivity between the three patient groups, typically in the alpha band. Differences between G1 and G2 (p < 0.001, corrected using permutation test) were mainly frontotemporal alterations. A statistically significant correlation (ρ = 0.49, p < 0.001) was also obtained between a proposed network-based index and the patients' cognitive score. Global properties of network topology in patients were relatively intact.

These findings indicate that functional connectivity decreases with the worsening of cognitive performance and loss of frontotemporal connectivity may be a promising neuromarker of cognitive impairment in Parkinson's disease.

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We test the use of dense-EEG to identify altered brain networks associated with cognitive phenotypes in Parkinson's disease.

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The functional connectivity decreases with the worsening of cognitive performance

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The loss of frontotemporal connectivity may be a promising neuromarker of cognitive impairment in Parkinson's disease.

Long-tract ileocolic intussusception due to mucinous adenocarcinoma of the ileocecal valve: a case report and literature review

Intussusception in adults lacks specific symptoms and is often diagnosed emergently when they present with obstruction. Though intussusception certainly varies in size and location, the increased likelihood of ischemia or obstruction make large intussusceptions very rare in the literature. A patient admitted to our facility for small bowel obstruction was found to have extensive intussusception from the right lower quadrant to the splenic flexure, where a lead point was identified. Histopathology revealed multiple satellite lesions surrounding the lead point tumor, which was found to be invasive mucinous adenocarcinoma of the ileocecal valve. While malignancy is found in 60% of lead point identifiable adult intussusceptions, a malignancy is always found in the case of an exceptionally large intussusception.

Electrochemical synthesis of diverse sulfonamide derivatives depending on the potential electrode and their antimicrobial activity evaluation

Electrochemical synthesis of two different series of sulfonamides was performed using the same precursors, 4-(4-nitrophenyl)urazole and arylsulfinic acids, by controlling the potential during electrolysis.