Distinguishing features of COVID-19 and non-COVID-19 febrile seizures in hospitalised children.

INTRODUCTION: Febrile seizures in children can be associated with various underlying conditions, including COVID-19. Differentiating COVID-19 and non-COVID-19 related febrile seizures is crucial for tailored patient management and for implementing appropriate infection control measures to prevent nosocomial transmission. This study aimed to describe the clinical features of children hospitalised for COVID-19 and non-COVID-19 febrile seizures and to identify factors that differentiate between the two groups. MATERIALS AND METHODS: This retrospective cross-sectional study involved children aged 6 months to 6 years who were hospitalised for febrile seizures in Hospital Tuanku Ja'afar Seremban (HTJS) from January 2021 to June 2022. Descriptive statistics were used to summarise the differences in demographics and clinical presentations. Logistic regression analyses were performed to identify factors associated with COVID-19 and non-COVID-19 febrile seizures. RESULTS: Of the 345 patients (median age 22 months, IQR 15- 32; 59.7% were males) included in the study, 130 (37.7%) tested positive for COVID-19, while 215 (62.3%) tested negative. There were no significant differences between both groups based on age, comorbidities, history of febrile seizures, seizure types, temperature on arrival, cough and rhinorrhoea. Multivariate analysis revealed that a family history of febrile seizures and leucocytosis were associated with increased odds of non-COVID-19 febrile seizures. In contrast, lymphopenia was associated with decreased odds. CONCLUSION: The clinical presentation of COVID-19 and non- COVID-19 febrile seizures are remarkably similar, highlighting the importance of including COVID-19 screening in febrile seizures workup. Full blood count readings may be potentially useful for differentiating between these conditions.

Bacterial valorization of agricultural-waste into a nano-sized cellulosic matrix for mitigating emerging pharmaceutical pollutants: An eco-benign approach.

For Bacterial Nanocellulose (BNC) production, standard methods are well-established, but there is a pressing need to explore cost-effective alternatives for BNC commercialization. This study investigates the feasibility of using syrup prepared from maize stalk as a valuable nutrient and sustainable carbon source for BNC production. Our study achieved a remarkable BNC production yield of 19.457 g L-1 by utilizing Komagataeibacter saccharivorans NUWB1 in combination with components from the Hestrin-Schramm (HS) medium. Physicochemical properties revealed that the obtained BNC exhibited a crystallinity index of 60.5 %, tensile strength of 43.5 MPa along with enhanced thermostability reaching up to 360 °C. N2 adsorption-desorption isotherm of the BNC displayed characteristics of type IV, indicating the presence of a mesoporous structure. The produced BNC underwent thorough investigation, focusing on its efficacy in addressing environmental concerns, particularly in removing emerging pharmaceutical pollutants like Metformin and Paracetamol. Remarkably, the BNC exhibited strong adsorption capabilities, aligning with the Langmuir isotherm and pseudo-second-order model. Thermodynamic analysis confirmed a spontaneous and endothermic adsorption process. Furthermore, the BNC showed potential for regeneration, enabling up to five recycling cycles. Cytotoxicity and oxidative stress assays validated the biocompatibility of BNC. Lastly, the BNC films displayed an impressive 88.73 % biodegradation within 21 days.

In-situ biofabrication of bacterial nanocellulose (BNC)/graphene oxide (GO) nano-biocomposite and study of its cationic dyes adsorption properties.

In the present study, bacterial nanocellulose/graphene oxide nano-biocomposites (BNC-GO-NBCs) were fabricated by Komagataeibacter saccharivorans NUWB1 using an in-situ method involving three time-dependent approaches. Physicochemical studies showed that the chosen dried BNC-GO-NBC possessed a three-dimensional interconnected porous structure of BNC with GO layers embedded within the BNC fibrils. BNC-GO-NBC had a crystallinity index of 74.21 %, higher thermostability up to 380 °C and could withstand a tensile load of 84.72 MPa. N2 adsorption-desorption isotherm of the BNC-GO-NBC was found to be of type IV, suggesting a mesoporous type structure with a total pore volume and surface area of 6.232e-04 cc g-1 and 10.498 m2. BNC-GO-NBC exhibited remarkable adsorption capacity for two cationic dyes, Rhodamine B (RhB) and Acridine Orange (AO), and the adsorption data conformed well to the Langmuir isotherm (R2 = 0.99) and pseudo-second-order model. Thermodynamic studies indicated that the adsorption process was spontaneous and endothermic. Additionally, the BNC-GO-NBC displayed the potential for regeneration, with the ability to be recycled up to five times. Further, the antibacterial activity, cell cytotoxicity and oxidative stress assays of the BNC-GO-NBC revealed its non-cytotoxic nature. The findings of the present investigation evidently suggest the potentiality of BNC-GO-NBC in the application of dye adsorption and other environmental applications.

Short-Term Aging of Pod-Derived Biochar Reduces Soil Cadmium Mobility and Ameliorates Cadmium Toxicity to Soil Enzymes and Tomato.

Contamination of agricultural soil with cadmium (Cd) has become a global concern because of its adverse effects on ecohealth and food safety. Soil amendment with biochar has become one of the phytotechnologies to reduce soil metal phyto-availability and its potential risks along the food chain. Biochar, derived from cocoa pod, was evaluated in soil Cd fractions (exchangeable, reducible, oxidizable, and residual) by modified Commission of the European Communities Bureau of Reference sequential extraction and its efficacy to ameliorate Cd toxicity to soil enzymes and leaf bioactive compounds. A pot experiment was conducted using Cd-spiked soil at 10 mg/kg with tomato (Solanum lycopersicum L.) at a biochar application rate of 1 and 3% (w/w) for 6 wk. The addition of biochar significantly reduced (p < 0.05) the exchangeable, reducible, and residual fractions by at least approximately 23%, with a consequential decrease in Cd root uptake and transport within tomato tissues. The activity of soil enzymes (catalase, dehydrogenase, alkaline phosphatase, and urease) was affected by Cd toxicity. However, with the exception of dehydrogenase, biochar application significantly enhanced the activity of these enzymes, especially at the 3% (w/w) rate. As for the secondary metabolites we studied, Cd toxicity was observed for glutathione, terpenoids, and total phenols. However, the biochar application rate of 1% (w/w) significantly ameliorated the effects of toxicity on the secondary metabolites. In conclusion, biochar demonstrated the potential to act as a soil amendment for Cd immobilization and thereby reduce the bioavailability of Cd in soil, mitigating food security risks. Environ Toxicol Chem 2021;40:3306-3316. © 2020 SETAC.

Designing of potential inhibitors against Staphylococcus aureus sortase A: Combined analogue and structure based approach with in vitro validation.

Staphylococcus aureus sortase A is an attractive target of Gram-positive bacteria that plays a crucial role in anchoring of surface proteins to peptidoglycan present in bacterial cell wall. Inhibiting sortase A is an elementary and essential effort in preventing the pathogenesis. In this context, in silico virtual screening of in-house database was performed using ligand based pharmacophore model as a filter. The developed pharmacophore model AAHR 11 consists of two acceptors, one hydrophobic and one ring aromatic feature. Top ranked molecule KKR1 was docked into the active site of the target. After profound analysis, it was analyzed and optimized based on the observations from its binding pose orientation. Upgraded version of KKR1 was KKR2 and has improved docking score, binding interactions and best fit in the binding pocket. KKR1 along with KKR2 were further validated using 100 ns molecular dynamic studies. Both KKR1 and KKR2 contain Indole-thiazolidine moiety and were synthesized. The disk diffusion assay has good initial results (ZI of KKR1, KKR2 were 24, 38 mm at 10 µg/mL and ZI of Ampicillin was 22 at 10 µg/mL) and calculated MICs of the molecules (KKR1 5.56±0.28 µg/mL, KKR2 1.32±0.12 µg/mL, Ampicillin 8±1.1 µg/mL) were in good agreement with standard drug Ampicillin. KKR1 has shown IC50 of 1.23±0.14 µM whereas the optimized lead molecule KKR2 show IC50 of 0.008±0.07 µM. Results from in silico were validated by in vitro studies and proved that indole-thiazolidine molecules would be useful for future development as lead molecules against S. aureus sortase A.

High dietary fat intake influences the activation of specific hindbrain and hypothalamic nuclei by the satiety factor oleoylethanolamide.

Chronic exposure to a diet rich in fats changes the gastrointestinal milieu and alters responses to several signals involved in the control of food intake. Oleoylethanolamide (OEA) is a gut-derived satiety signal released from enterocytes upon the ingestion of dietary fats. The anorexigenic effect of OEA, which requires intestinal PPAR-alpha receptors and is supposedly mediated by vagal afferents, is associated with the induction of c-fos in several brain areas involved in the control of food intake, such as the nucleus of the solitary tract (NST) and the hypothalamic paraventricular (PVN) and supraoptic nuclei (SON). In the present study we investigated whether the exposure to a high fat diet (HFD) alters the hindbrain and hypothalamic responses to OEA. To this purpose we evaluated the effects of OEA at a dose that reliably inhibits eating (10mg/kg i.p.) on the induction of c-fos in the NST, area postrema (AP), PVN and SON in rats maintained either on standard chow or a HFD. We performed a detailed analysis of the different NST subnuclei activated by i.p. OEA and found that peripheral OEA strongly activates c-fos expression in the AP, NST and in the hypothalamus of both chow and HFD fed rats. The extent of c-fos expression was, however, markedly different between the two groups of rats, with a weaker activation of selected NST subnuclei and stronger activation of the PVN in HFD-fed than in chow-fed rats. HFD-fed rats were also more sensitive to the immediate hypophagic action of OEA than chow-fed rats. These effects may be due to a decreased sensitivity of vagal afferent fibers that might mediate OEA's actions on the brain and/or an altered sensitivity of brain structures to OEA.

Studies of detailed biofilm characterization on fly ash concrete in comparison with normal and superplasticizer concrete in seawater environments.

In cooling water systems, many concrete structures in the form of tanks, pillars and reservoirs that come in contact with aggressive seawater are being deteriorated by chemical and biological factors. The nuclear industry has decided to partially replace the Portland cement with appropriate pozzolans such as fly ash, which could densify the matrix and make the concrete impermeable. Three types of concrete mixes, viz., normal concrete (NC), concrete with fly ash and superplasticizer (FA) and concrete with only superplasticizer (SP) were fabricated for short- and long-term exposure studies and for screening out the better concrete in seawater environments. Biofilm characterization studies and microscopic studies showed excellent performance of FA concrete compared to the other two. Laboratory exposure studies in pure cultures of Thiobacillus thiooxidans and Fusarium oxysporum were demonstrated for the inhibition of microbial growth on fly ash. Epifluorescence and scanning electron microscopic studies supported the better performance of the FA specimen. Thus, the present study clearly showed that FA concrete is less prone to biofilm formation and biodeterioration.

Phantom limbs and neural plasticity.

The study of phantom limbs has received tremendous impetus from recent studies linking changes in cortical topography with perceptual experience. Systematic psychophysical testing and functional imaging studies on patients with phantom limbs provide 2 unique opportunities. First, they allow us to demonstrate neural plasticity in the adult human brain. Second, by tracking perceptual changes (such as referred sensations) and changes in cortical topography in individual patients, we can begin to explore how the activity of sensory maps gives rise to conscious experience. Finally, phantom limbs also allow us to explore intersensory effects and the manner in which the brain constructs and updates a "body image" throughout life.

Psychophysical evidence for boundary and surface systems in human vision.

Psychophysical evidence is given for the existence of two distinct systems in human vision: a fast, sign-invariant system concerned with extracting contours and a slower, sign-sensitive system concerned with assigning surface color. A class of stimuli we developed seems to selectively activate the fast, contour system. This stimulus is formed by adjacent fields of black and white spots, which flicker in counterphase at 15 Hz, on a uniform gray field. Although subjects can not discriminate the temporal phase relationship between the fields of spots, they can, nevertheless see a "Phantom Contour" separating the two indiscriminable fields. The surface characteristics (temporal phase relationship of the spots) can only be seen when the stimulus is significantly slower (flicker < 7 Hz). In addition, phantom contours disappear with equiluminant spots but can be seen with very low contrast spots (< 10% contrast), and are enhanced with peripheral viewing. Taken together, the results suggest that the fast contour-extracting system may be the magnocellular system or a magno-recipient area. Implications for a stimulus which could isolate a contour extracting system, or a magno-recipient area are discussed.

Synaesthesia in phantom limbs induced with mirrors.

Although there is a vast clinical literature on phantom limbs, there have been no experimental studies on the effects of visual input on phantom sensations. We introduce an inexpensive new device--a 'virtual reality box'--to resurrect the phantom visually to study inter-sensory effects. A mirror is placed vertically on the table so that the mirror reflection of the patient's intact had is 'superimposed' on the felt position of the phantom. We used this procedure on ten patients and found the following results. 1. In six patients, when the normal hand was moved, so that the phantom was perceived to move in the mirror, it was also felt to move; i.e. kinesthetic sensations emerged in the phantom. In D.S. this effect occurred even though he had never experienced any movements in the phantom for ten years before we tested him. He found the return of sensations very enjoyable. 2. Repeated practice led to a permanent 'disappearance' of the phantom arm in patient D.S. and the hand became telescoped into the stump near the shoulder. 3. Using an optical trick, impossible postures--e.g. extreme hyperextension of the fingers--could be induced visually in the phantom. In one case this was felt as a transient 'painful tug' in the phantom. 4. Five patients experienced involuntary painful 'clenching spasms' in the phantom hand and in four of them the spasms were relieved when the mirror was used to facilitate 'opening' of the phantom hand; opening was not possible without the mirror. 5. In three patients, touching the normal hand evoked precisely localized touch sensations in the phantom. Interestingly, the referral was especially pronounced when the patients actually 'saw' their phantom being touched in the mirror. Indeed, in a fourth patient (R.L.) the referral occurred only if he saw his phantom being touched: a curious form of synaesthesia. These experiments lend themselves readily to imaging studies using PET and fMRI. Taken collectively, they suggest that there is a considerable amount of latent plasticity even in the adult human brain. For example, precisely organized new pathways, bridging the two cerebral hemispheres, can emerge in less than three weeks. Furthermore, there must be a great deal of back and forth interaction between vision and touch, so that the strictly modular, hierarchical model of the brain that is currently in vogue needs to be replaced with a more dynamic, interactive model, in which 're-entrant' signalling plays the main role.

Rapid adaptive camouflage in tropical flounders.

Despite the commonly held view that flatfish can change their surface markings to match their background pattern, there have been few systematic studies and it has recently been claimed that their capacity for such adaptive changes is minimal. Here we show that the tropical flatfish Bothus ocellatus can achieve pattern-matching with surprising fidelity. By adjusting the contrast of different sets of 'splotches' of different grain size (or spatial frequency) on the skin, the fish can blend into a wide range of background textures in just 2-8 seconds.

On the perception of illusory contours.

Illusory contours are invoked by the visual system to account for otherwise inexplicable gaps in the image. We report three sets of novel observations on illusory contours. First, when an illusory square is superimposed on a checkerboard pattern there is a considerable enhancement of the contours so long as they are exactly coincident with the borders of the checks. If the checks are misaligned, on the other hand, the illusory contours associated with the pacman edges disappear and a novel percept emerges: the contours of the checks nearest to the illusory square appear enhanced. This result implies that subjective contours are generated by intermediate-level contour interactions rather than the top-down processes of three-dimensional interpretation. Second, we find that steady fixation for as little as 4 sec leads to a complete disappearance of the enhanced illusory contours caused, presumably, by adaptation or "fatigue" of cells that signal these contours. Such adaptation occurred even when the illusory contours were rendered invisible by displaying them on a misaligned checkerboard, suggesting that the adaptation occurs prior to the vetoing of the signal by the checks. Third, we found that illusory contours persist for a surprisingly long time (0.3 sec) after the inducing elements have been switched off. These results suggest that the stimuli we have designed ("enhanced illusory contours") might provide a novel probe for dissecting different stages involved in the processing of illusory contours and for understanding how the visual system combines different types of contours to construct object boundaries.

Perceptual correlates of massive cortical reorganization.

Following long-term deafferentation of one upper limb in adult primates, the cortical areas corresponding to that limb become responsive to stimuli applied to the face. To explore this phenomenon, we studied some patients after upper limb amputation. In patient VQ, stimuli applied to the lower face or 7 cm above the stump evoked precisely localized referred sensations in individual digits which were often modality specific. Similarly, in another patient, WK several complete somatotopic representations of the phantom limb were found, on the face, chest and axilla, indicating the emergence of such maps in regions remote from the stump. These effects may be a direct perceptual correlate of the physiological observations of Merzenick et al (1984), Wall (1977) and Pons et al (1991).

Interocular torsional disparity and visual cortical development in the cat.

1. The present experiments were designed to assess the effects of relatively large optically induced interocular torsional disparities on the developing kitten visual cortex. Kittens were reared with restricted visual experience. Three groups viewed a normal visual environment through goggles fitted with small prisms that introduced torsional disparities between the left and right eyes' visual fields, equal but opposite in the two eyes. Kittens in the +32 degrees goggle rearing condition experienced a 16 degrees counterclockwise rotation of the left visual field and a 16 degrees clockwise rotation of the right visual field; in the -32 degrees goggle condition the rotations were clockwise in the left eye and counterclockwise in the right. In the control (0 degree) goggle condition, the prisms did not rotate the visual fields. Three additional groups viewed high-contrast square-wave gratings through Polaroid filters arranged to provide a constant 32 degrees of interocular orientation disparity. 2. Recordings were made from neurons in visual cortex around the border of areas 17 and 18 in all kittens. Development of cortical ocular dominance columns was severely disrupted in all the experimental (rotated) rearing conditions. Most cells were classified in the extreme ocular dominance categories 1, 2, 6, and 7. Development of the system of orientation columns was also affected: among the relatively few cells with oriented receptive fields in both eyes, the distributions of interocular disparities in preferred stimulus orientation were centered near 0 degree but showed significantly larger variances than in the control condition.(ABSTRACT TRUNCATED AT 250 WORDS)