Astrocytes in functional recovery following central nervous system injuries.

Astrocytes are increasingly recognised as partaking in complex homeostatic mechanisms critical for regulating neuronal plasticity following central nervous system (CNS) insults. Ischaemic stroke and traumatic brain injury are associated with high rates of disability and mortality. Depending on the context and type of injury, reactive astrocytes respond with diverse morphological, proliferative and functional changes collectively known as astrogliosis, which results in both pathogenic and protective effects. There is a large body of research on the negative consequences of astrogliosis following brain injuries. There is also growing interest in how astrogliosis might in some contexts be protective and help to limit the spread of the injury. However, little is known about how astrocytes contribute to the chronic functional recovery phase following traumatic and ischaemic brain insults. In this review, we explore the protective functions of astrocytes in various aspects of secondary brain injury such as oedema, inflammation and blood-brain barrier dysfunction. We also discuss the current knowledge on astrocyte contribution to tissue regeneration, including angiogenesis, neurogenesis, synaptogenesis, dendrogenesis and axogenesis. Finally, we discuss diverse astrocyte-related factors that, if selectively targeted, could form the basis of astrocyte-targeted therapeutic strategies to better address currently untreatable CNS disorders.

MiR-182 Inhibition Protects Against Experimental Stroke in vivo and Mitigates Astrocyte Injury and Inflammation in vitro via Modulation of Cortactin Activity.

Ischemic stroke remains a devastating cerebrovascular disease that accounts for a high proportion of mortality and disability worldwide. MicroRNAs (miRNAs) are a class of small non-coding RNAs that are responsible for regulation of post-transcriptional gene expression, and growing evidence supports a role for miRNAs in stroke injury and recovery. The current study examined the role of miR-182 in experimental stroke using both in vitro and in vivo models of ischemic injury. Brain levels of miR-182 significantly increased after transient middle cerebral artery occlusion (MCAO) in mice and in primary astrocyte cultures subjected to combined oxygen-glucose deprivation/reperfusion (OGD/R) injury. In vivo, stroke volume and neurological score were significantly improved by pre-treatment with miR-182 antagomir. Astrocyte cultures stressed with OGD/R resulted in mitochondrial fragmentation and downregulation of cortactin, an actin-binding protein. Inhibition of miR-182 significantly preserved cortactin expression, reduced mitochondrial fragmentation and improved astrocyte survival after OGD/R. In parallel, lipopolysaccharide (LPS)-induced nitric-oxide release in astrocyte cultures was significantly reduced by miR-182 inhibition, translating to reduced injury in primary neuronal cultures subjected to conditioned medium from LPS-treated astrocytes. These findings identify miR-182 and/or cortactin as potential clinical targets to preserve mitochondrial structure and mitigate neuroinflammation and cell death after ischemic stroke.

The Application of Fractal Transform and Entropy for Improving Fault Tolerance and Load Balancing in Grid Computing Environments.

This paper applies the entropy-based fractal indexing scheme that enables the grid environment for fast indexing and querying. It addresses the issue of fault tolerance and load balancing-based fractal management to make computational grids more effective and reliable. A fractal dimension of a cloud of points gives an estimate of the intrinsic dimensionality of the data in that space. The main drawback of this technique is the long computing time. The main contribution of the suggested work is to investigate the effect of fractal transform by adding R-tree index structure-based entropy to existing grid computing models to obtain a balanced infrastructure with minimal fault. In this regard, the presented work is going to extend the commonly scheduling algorithms that are built based on the physical grid structure to a reduced logical network. The objective of this logical network is to reduce the searching in the grid paths according to arrival time rate and path's bandwidth with respect to load balance and fault tolerance, respectively. Furthermore, an optimization searching technique is utilized to enhance the grid performance by investigating the optimum number of nodes extracted from the logical grid. The experimental results indicated that the proposed model has better execution time, throughput, makespan, latency, load balancing, and success rate.

Tetramethylpyrazine inhibited hypoxia-induced expression of calcium-sensing receptors in pulmonary artery smooth muscle cells in chickens.

Tetramethylpyrazine (TMP) is a biologically active ingredient, which is isolated from a popularChinese medicinal plant. It has been used effectively to treat ischemic heart problems, cerebrovascular and thrombotic vascular diseases. This study was designed to evaluate the effect of TMP on calciumsensing receptors in pulmonary artery smooth muscle in chickens. For this purpose forty day-old chicks were distributed into five groups: the control group, the hypoxia group (kept under low Oxygen treatment), and TMP groups (kept under low Oxygen treatment along with treatment of different concentrations of TMP). The pulmonary artery smooth muscle cells were also cultured on 6-well plates in high glucose culture medium and divided into the same five groups. We used in vivo and in vitro study models by applying immunohistochemistry, RT-qPCR assay and Western blotting analysis. Our results showed that pre-incubation with hypoxia markedly stimulated the activation of calcium-sensing receptor (CaSR) in pulmonary artery smooth muscle cells (PASMCs). The TMP decreased the mRNA and protein levels of CaSR. Treatment with TMP clearly inhibited the activation of all CaSR in a dose-dependent manner. Our data demonstrated that TMP can down-regulate the expression of CaSR. Therefore, these findings provide a new target to treat pulmonary arterial hypertension (PAH) under hypoxic conditions.

Patient-specific finite element estimated femur strength as a predictor of the risk of hip fracture: the effect of methodological determinants.

UNLABELLED: A finite element modelling pipeline was adopted to predict femur strength in a retrospective cohort of 100 women. The effects of the imaging protocol and the meshing technique on the ability of the femur strength to classify the fracture and the control groups were analysed. INTRODUCTION: The clinical standard to estimate the risk of osteoporotic hip fracture is based on the areal bone mineral density (aBMD). A few retrospective studies have concluded that finite element (FE)-based femoral strength is a better classifier of fracture and control groups than the aBMD, while others could not find significant differences. We investigated the effect of the imaging protocol and of the FE modelling techniques on the discriminatory power of femoral strength. METHODS: A retrospective cohort of 100 post-menopausal women (50 with hip fracture, 50 controls) was examined. Each subject received a dual-energy absorptiometry (DXA) exam and a computed tomography (CT) scan of the proximal femur region. Each case was modelled a number of times, using different modelling pipelines, and the results were compared in terms of accuracy in discriminating the fracture and the control cases. The baseline pipeline involved local anatomical orientation and mesh morphing. Revised pipelines involved global anatomical orientation using a full-femur atlas registration and an optimised meshing algorithm. Minimum physiological (MPhyS) and pathological (MPatS) strengths were estimated for each subject. Area under the receiver operating characteristic (ROC) curve (AUC) was calculated to compare the ability of MPhyS, MPatS and aBMD to classify the control and the cases. RESULTS: Differences in the modelling protocol were found to considerably affect the accuracy of the FE predictors. For the most optimised protocol, logistic regression showed aBMDNeck, MPhyS and MPatS to be significantly associated with the facture status, with AUC of 0.75, 0.75 and 0.79, respectively. CONCLUSION: The study emphasized the necessity of modelling the whole femur anatomy to develop a robust FE-based tool for hip fracture risk assessment. FE-strength performed only slightly better than the aBMD in discriminating the fracture and control cases. Differences between the published studies can be explained in terms of differences in the modelling protocol and cohort design.

Natural Polyphenols in Cancer Chemoresistance.

Resistance to chemotherapy remains a major impediment to the management of most types of cancer. Both intrinsic and acquired drug resistance are mediated by several cellular and molecular mechanisms, including alternative growth-signaling pathways unaffected by specific therapies, alterations in the tumor microenvironment (e.g., hypoxia and angiogenesis), and active transport of drugs out of the cell. Epidemiological studies have validated an inverse correlation between the consumption of dietary polyphenols and the risk of cancer, which has been attributed to polyphenol antioxidant capacity and their potential to inhibit activation of procarcinogens, cancer cell proliferation, metastasis, and angiogenesis, and inhibition or downregulation of active drug efflux transporters. Moreover, polyphenols can induce apoptosis in cancer cells and modulate immune responses and inflammatory cascades. Augmentation of the efficacy of chemotherapy and prevention of multidrug resistance are other important effects of dietary polyphenols that deserve further research, especially after the discovery of tight "crosstalk" between aberrant growth signaling and metabolic dysfunction in cancer cells. In this review, we cover what is currently known about the role of natural polyphenolic compounds in overcoming cancer drug resistance mediated by diverse primary and secondary resistance mechanisms.

Identification and Fibrosis Staging of Hepatitis C Patients Using the Electronic Medical Record System.

BACKGROUND AND AIMS: The aim of this study was to noninvasively assess the severity of chronic hepatitis C virus (HCV) in large patient populations. It would be helpful if fibrosis scores could be calculated solely on the basis of data contained in the patients' electronic medical records (EMR). We performed a pilot study to identify all HCV-infected patients in a large health care system, and predict their fibrosis stage on the basis of demographic and laboratory data using common data from their EMR. MATERIALS AND METHODS: HCV-infected patients were identified using the EMR. The liver biopsies of 191 HCV patients were graded using the Ishak and Metavir scoring systems. Demographic and laboratory data were extracted from the EMR and used to calculate the aminotransferase to platelet ratio index, Fib-4, Fibrosis Index, Forns, Göteborg University Cirrhosis Index, Lok Index, and Vira-HepC. RESULTS: In total, 869 HCV-infected patients were identified from a population of over 1 million. In the subgroup of patients with liver biopsies, all 7 algorithms were significantly correlated with the fibrosis stage. The degree of correlation was moderate, with correlation coefficients ranging from 0.22 to 0.60. For the detection of advanced fibrosis (Metavir 3 or 4), the areas under the receiver operating characteristic curve ranged from 0.71 to 0.84, with no significant differences between the individual scores. Sensitivities, specificities, and positive and negative predictive values were within the previously reported range. All scores tended to perform better for higher fibrosis stages. CONCLUSIONS: Our study demonstrates that HCV-infected patients can be identified and their fibrosis staged using commonly available EMR-based algorithms.

Antimicrobial resistance among aerobic biofilm producing bacteria isolated from chronic wounds in the tertiary care hospitals of Peshawar, Pakistan.

OBJECTIVE: Chronic wound infections impose major medical and economic costs on health-care systems, cause significant morbidity, mortality and prolonged hospitalisation. The presence of biofilm producing bacteria in these wounds is considered as an important virulence factor that leads to chronic implications including ulceration. The undertaken study aimed to isolate and identify the biofilm aerobic bacterial pathogens from patients with chronic wound infections, and determine their antibiotics resistance profiles Method: During this study, swab specimens were collected from patients with chronic wounds at teaching hospitals of Peshawar, Pakistan between May 2013 and June 2014. The isolated aerobic bacterial pathogens were identified on the basis of standard cultural characteristics and biochemical tests. Antibiotics resistance profiles of biofilm producing bacteria against selected antibiotics were then determined. RESULTS: Among the chronic wound infections, diabetic foot ulcers were most common 37 (37%), followed by surgical ulcers 27 (27%). Chronic wounds were common in male patients older than 40 years. Among the total 163 isolated bacterial pathogens the most prevalent bacterial species were Pseudomonas aeruginosa 44 (27%), Klebsiella pneumoniae 26 (16%), Staphylococcus species 22 (14%) and Streptococcus spp. 21 (13%). The isolation rate of bacterial pathogens was high among patients with diabetic foot ulcers 83 (50.9%). Among bacterial isolates, 108 (66.2%) were observed as biofilm producers while 55 (33.8%) did not form biofilm in our model. The investigated biofilm producing bacterial isolates showed comparatively high resistance against tested antibiotics compared to non-biofilm producing bacterial isolates. The most effective antibiotics were amikacine and cefepime against all isolates. CONCLUSION: Increased multidrug resistance in biofilm producing bacteria associated with chronic wounds was observed in this study. Judicious use of antibiotics is needed to control the wound associated biofilm associated pathogens.

Stretchable liquid-crystal blue-phase gels.

Liquid-crystalline polymers are materials of considerable scientific interest and technological value. An important subset of these materials exhibit rubber-like elasticity, combining the optical properties of liquid crystals with the mechanical properties of rubber. Moreover, they exhibit behaviour not seen in either type of material independently, and many of their properties depend crucially on the particular mesophase employed. Such stretchable liquid-crystalline polymers have previously been demonstrated in the nematic, chiral-nematic, and smectic mesophases. Here, we report the fabrication of a stretchable gel of blue phase I, which forms a self-assembled, three-dimensional photonic crystal that remains electro-optically switchable under a moderate applied voltage, and whose optical properties can be manipulated by an applied strain. We also find that, unlike its undistorted counterpart, a mechanically deformed blue phase exhibits a Pockels electro-optic effect, which sets out new theoretical challenges and possibilities for low-voltage electro-optic devices.

Silver nanoparticles embedded mesoporous SiO2 nanosphere: an effective anticandidal agent against Candida albicans 077.

Candida albicans is a diploid fungus that causes common infections such as denture stomatitis, thrush, urinary tract infections, etc. Immunocompromised patients can become severely infected by this fungus. Development of an effective anticandidal agent against this pathogenic fungus, therefore, will be very useful for practical application. In this work, Ag-embedded mesoporous silica nanoparticles (mSiO2@AgNPs) have successfully been synthesized and their anticandidal activities against C. albicans have been studied. The mSiO2@AgNPs nanoparticles (d ∼ 400 nm) were designed using pre-synthesized Ag nanoparticles and tetraethyl orthosilicate (TEOS) as a precursor for SiO2 in the presence of cetyltrimethyl ammonium bromide (CTAB) as an easily removable soft template. A simple, cost-effective, and environmentally friendly approach has been adopted to synthesize silver (Ag) nanoparticles using silver nitrate and leaf extract of Azadirachta indica. The mesopores, with size-equivalent diameter of the micelles (d = 4-6 nm), were generated on the SiO2 surface by calcination after removal of the CTAB template. The morphology and surface structure of mSiO2@AgNPs were characterized through x-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), particle size analysis (PSA), atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), Brunauer-Emmett-Teller (BET) and high-resolution transmission electron microscopy (HRTEM). The HRTEM micrograph reveals the well-ordered mesoporous structure of the SiO2 sphere. The antifungal activities of mSiO2@AgNPs on the C. albicans cell have been studied through microscopy and are seen to increase with increasing dose of mSiO2@AgNPs, suggesting mSiO2@AgNPs to be a potential antifungal agent for C. albicans 077.

First Report of Fusarium oxysporum f. sp. cubense Tropical Race 4 Associated with Panama Disease of Banana outside Southeast Asia.

Fusarium wilt or Panama disease of banana, caused by Fusarium oxysporum f. sp. cubense (Foc), is among the most destructive plant diseases (3). Race 1 ravaged 'Gros Michel'-based export trades until the cultivar was replaced by resistant Cavendish cultivars. However, a new variant of Foc, tropical race 4 (TR4), was identified in Southeast Asia in 1992 and has spread throughout the region (3). Cavendish clones, which are most important in subsistence and export production, are among the wide range of cultivars that are affected, and there is a huge concern that TR4 will further disseminate in Africa since its presence was announced in November 2013 and move into Latin America, thereby threatening other vital banana-growing regions. In Jordan, Cavendish bananas are produced on 1,000 to 1,500 ha in the Jordan Valley (32°N, 35.5°E). In 2006, symptoms of Fusarium wilt were observed and sampled for the isolation of Foc. On half-strength PDA amended with 100-ppm streptomycin sulfate, pale salmon-colored colonies with floccose mycelia developed consistently from surface-disinfested xylem. Single microconidia from these colonies were transferred to half-strength PDA, and conidia and mycelia from these monospore colonies were stored at -80°C in 15% glycerol. On banana leaf agar (Co60-irradiated leaf tissue on water agar), isolates resembled F. oxysporum phenotypically by producing infrequent three- to five-celled macroconidia, copious, usually aseptate microconida on monophialides, and terminal and intercalary chlamydospores after 2 weeks (2). With nitrate-nonutilizing (nit) mutants and testers for different vegetative compatibility groups (VCGs), each of seven examined monospore isolates were placed in VCG 01213, which contains only strains of TR4 (3). Total DNA was extracted from six isolates and PCR analyses, which confirmed their identity as TR4 (1). Subsequently, one of the isolates (JV11) was analyzed for pathogenicity. Inoculum production and inoculation were according to (1) by dipping (30 min) root-wounded 10-week-old plants of the Cavendish cv. Grand Naine in 2 liters of spore suspension (1.0 × 106 spores/ml). Inoculated plants were then placed in sand in 3-liter pots under 28°C, 70% relative humidity, and a 16/8-h light/darkness photoperiod. Sets of three plants were each treated with either JV11 or two TR4 controls (isolate II-5 and a strain isolated from an affected Cavendish plant in Mindanao, Philippines, both of which were diagnosed as TR4 by PCR and pathogenicity analyses). Control sets were either treated with race 1 originating from Cruz das Almas, Bahia, Brazil (1), or water. After 2 weeks, plants inoculated with JV11 and TR4 controls produced typical symptoms of Fusarium wilt. After 4 weeks, tissue was collected from all plants and plated on Komada's medium. TR4 was directly confirmed by PCR (1), either directly from symptomatic plants (JV11 and TR4 controls), or from isolates that were recovered from these plants. Nothing was re-isolated from race 1 inoculated plants and water controls, which remained asymptomatic. This is the first report of TR4 affecting Cavendish outside Southeast Asia, is its northernmost outbreak, and represents a dangerous expansion of this destructive race. Currently, 80% of the Jordan Valley production area is affected by Fusarium wilt, and 20 to 80% of the plants are affected in different farms. References: (1) M. A. Dita et al. Plant Pathol. 59:348, 2010. (2) J. F. Leslie and B. A. Summerell. The Fusarium Lab Manual. Blackwell, Ames, 2006. (3) R. C. Ploetz. Phytopathology 96:653, 2006.

Socioeconomic status is associated with greater hazard of post-discharge mortality than race, gender, and ballistic injury mechanism in a young, healthy, orthopedic trauma population.

OBJECTIVES: To explore the utility of legacy demographic factors and ballistic injury mechanism relative to popular markers of socioeconomic status as prognostic indicators of 10-year mortality following hospital discharge in a young, healthy patient population with isolated orthopedic trauma injuries. METHODS: A retrospective cohort study was performed to evaluate patients treated at an urban Level I trauma center from January 1, 2003, through December 31, 2016. Current Procedure Terminology (CPT) codes were used to identify upper and lower extremity fracture patients undergoing operative fixation. Exclusion criteria were selected to yield a patient population of isolated extremity trauma in young, otherwise healthy individuals between the ages of 18 and 65 years. Variables collected included injury mechanism, age, race, gender, behavior risk factors, Area Deprivation Index (ADI), and insurance status. The primary outcome was post-discharge mortality, occurring at any point during the study period. RESULTS: We identified 2539 patients with operatively treated isolated extremity fractures. The lowest two quartiles of socioeconomic status (SES) were associated with higher hazard of mortality than the highest SES quartile in multivariable analysis (Quartile 3 HR: 2.2, 95% CI: 1.2-4.1, p = 0.01; Quartile 4 HR: 2.2, 95% CI: 1.1-4.3, p = 0.02). Not having private insurance was associated with higher mortality hazard in multivariable analysis (HR 2.0, 95% CI: 1.3-3.2, p = 0.002). The presence of any behavioral risk factor was associated with higher mortality hazard in univariable analysis (HR: 1.8, p < 0.05), but this difference did not reach statistical significance in multivariable analysis (HR: 1.4, 95%: 0.8-2.3, p = 0.20). Injury mechanism (ballistic versus blunt), gender, and race were not associated with increased hazard of mortality (p > 0.20). CONCLUSION: Low SES is associated with a greater hazard of long-term mortality than ballistic injury mechanism, race, gender, and medically diagnosable behavioral risk factors in a young, healthy orthopedic trauma population with isolated extremity injury.

Predicting Which Species of Bacteria Will Cause an Infection After Fracture Surgery.

The aim of this study was to develop and validate risk prediction models for deep surgical site infection (SSI) caused by specific bacterial pathogens after fracture fixation. A retrospective case-control study was conducted at a level I trauma center. Fifteen candidate predictors of the bacterial pathogens in deep SSI were evaluated to develop models of bacterial risk. The study included 441 patients with orthopedic trauma with deep SSI after fracture fixation and 576 control patients. The main outcome measurement was deep SSI cultures positive for methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S aureus (MRSA), gram-negative rods (GNRs), anaerobes, or polymicrobial infection within 1 year of injury. Prognostic models were developed for five bacterial pathogen outcomes. Mean area under the curve ranged from 0.70 (GNRs) to 0.74 (polymicrobial). Strong predictors of MRSA were American Society of Anesthesiologists (ASA) classification of III or greater (odds ratio [OR], 3.4; 95% CI, 1.6-8.0) and time to fixation greater than 7 days (OR, 3.4; 95% CI, 1.9-5.9). Gustilo type III fracture was the strongest predictor of MSSA (OR, 2.5; 95% CI, 1.6-3.9) and GNRs (OR, 3.4; 95% CI, 2.3-5.0). ASA classification of III or greater was the strongest predictor of polymicrobial infection (OR, 5.9; 95% CI, 2.7-15.5) and was associated with increased odds of GNRs (OR, 2.7; 95% CI, 1.5-5.5). Our models predict the risk of MRSA, MSSA, GNR, anaerobe, and polymicrobial infections in patients with fractures. The models might allow for modification of preoperative antibiotic selection based on the particular pathogen posing greatest risk for this patient population. [Orthopedics. 2024;47(1):e19-e25.].

Congenital colloid cyst with astigmatism in adult male patient: a rare case report.

Introduction and importance: Colloid cysts are rare brain tumors that can cause headaches, memory problems, and vision issues. Early diagnosis and treatment are crucial to prevent complications. Case presentation: The authors report a case of a patient in their 20s with a 2-year history of headaches and blurry vision. A computed tomography (CT) scan revealed a colloid cyst in the third ventricle. The patient was diagnosed with astigmatism and managed with corrective lenses and regular CT scans. Clinical discussion: The patient's astigmatism may be linked to the colloid cyst, potentially due to migraines triggered by the cyst's location. Further research is needed to understand this relationship. Conclusion: This case highlights the potential for colloid cysts to contribute to vision problems. Careful evaluation and individualized management are essential for patients with colloid cysts and vision disturbances.

Clinical Outcomes of Intravesical Prostatic Protrusion in Patients With Benign Prostatic Hyperplasia.

Background Benign prostatic hyperplasia (BPH) is a disorder that is characterized by the hyperplasia of the cellular elements of the prostate, leading to an enlarged prostate. One of the parameters affecting urinary outflow is intravesical prostatic protrusion (IPP). It is a phenomenon wherein the enlargement of the prostate protrudes into the bladder along the plane of least resistance. This condition can lead to various clinical effects, including symptoms such as the feeling of incomplete void and weak, interrupted urine stream. Hence, investigating the potential associations between different grades of IPP and clinical urological outcomes holds crucial implications for optimizing patient care, refining risk stratification, and enhancing treatment approaches. Methodology We examined patients who were following up at the urology outpatient clinics due to BPH between June 1, 2021, and December 31, 2022. All patients included in this study were required to undergo a transabdominal prostate ultrasound. Patient records were reviewed for various factors, including demographic stratification, the presence of urine routine or culture with evidence of urinary tract infection (UTI) within the past two years, and whether patients were scheduled for surgical intervention. The radiological parameters were recorded by viewing the midsagittal and transverse ultrasound images retrospectively by two specialist radiology physicians. The parameters measured included IPP Grade, prostate volume (PV), presence of bladder stones, anatomical abnormalities (such as bladder diverticulum), and post-void volume. Results The total sample size was 184 patients. Out of these, 53 (28.8%) had IPP Grade I, 72 (39.1%) were classified as Grade II, 42 (22.8%) had Grade III, and 17 (9.2%) were categorized as Grade IV. The data collected also showed that 12 (6.5%) patients had bladder stones on ultrasound examination. Additionally, 17 (9.2%) patients had bladder diverticulum. Furthermore, when controlled for age and PV, multivariate analysis using logistic regression models to calculate the odds ratio (OR) showed that increasing IPP Grade is associated with an increased risk of developing UTIs, acute urinary retention, and the need for surgical intervention. The highest risk group of patients is IPP Grade IV, with odds ratios (ORs) of 6.8, 7.2, and 6.4 for developing UTIs, experiencing acute urinary retention, and requiring surgical intervention, respectively. Conclusions The results provide compelling evidence of the adverse relationships between higher grades of IPP and worsening urological outcomes and patient morbidity. Hence, we recommend further studies be conducted on the clinical effects of IPP and that these measurements should be considered as part of routine ultrasound prostate imaging to aid in the management of BPH cases.

Blue-phase templated fabrication of three-dimensional nanostructures for photonic applications.

A promising approach to the fabrication of materials with nanoscale features is the transfer of liquid-crystalline structure to polymers. However, this has not been achieved in systems with full three-dimensional periodicity. Here we demonstrate the fabrication of self-assembled three-dimensional nanostructures by polymer templating blue phase I, a chiral liquid crystal with cubic symmetry. Blue phase I was photopolymerized and the remaining liquid crystal removed to create a porous free-standing cast, which retains the chiral three-dimensional structure of the blue phase, yet contains no chiral additive molecules. The cast may in turn be used as a hard template for the fabrication of new materials. By refilling the cast with an achiral nematic liquid crystal, we created templated blue phases that have unprecedented thermal stability in the range -125 to 125 °C, and that act as both mirrorless lasers and switchable electro-optic devices. Blue-phase templated materials will facilitate advances in device architectures for photonics applications in particular.

Bacteriophage Infection of the Marine Bacterium Shewanella glacialimarina Induces Dynamic Changes in tRNA Modifications.

Viruses are obligate intracellular parasites that, throughout evolution, have adapted numerous strategies to control the translation machinery, including the modulation of post-transcriptional modifications (PTMs) on transfer RNA (tRNA). PTMs are critical translation regulators used to further host immune responses as well as the expression of viral proteins. Yet, we lack critical insight into the temporal dynamics of infection-induced changes to the tRNA modification landscape (i.e., 'modificome'). In this study, we provide the first comprehensive quantitative characterization of the tRNA modificome in the marine bacterium Shewanella glacialimarina during Shewanella phage 1/4 infection. Specifically, we show that PTMs can be grouped into distinct categories based on modification level changes at various infection stages. Furthermore, we observe a preference for the UAC codon in viral transcripts expressed at the late stage of infection, which coincides with an increase in queuosine modification. Queuosine appears exclusively on tRNAs with GUN anticodons, suggesting a correlation between phage codon usage and PTM modification. Importantly, this work provides the basis for further studies into RNA-based regulatory mechanisms employed by bacteriophages to control the prokaryotic translation machinery.

Prevalence of Gram positive bacteria in the affected individuals of Otitis media with effusion from the indigenous population of Southern Punjab, Pakistan: first report.

Otitis media with effusion (OME) is a type of otitis media (OM) characterized by the presence of fluid behind intact tympanic membrane and is one of the most common diseases of early childhood. It is an infectious disease associated with the presence of many pathogenic bacteria in the middle ear of affected individuals. This study was aimed to determine the prevalence of Gram-positive bacteria from the middle ear of OME patients in the population of Southern Punjab, Pakistan. The incidence of OME under comprehensive healthcare setting was investigated in patients who consulted at the department of ear, throat and nose, Bahawal Victoria Hospital (BVH), Bahawalpur, from December, 2019 to May, 2021. Ear swabs were taken from affected and normal individuals. After culturing bacteria from the ear swabs, microscopic analysis and biochemical tests were performed to characterize the cultured Gram-positive bacteria. Out of 352 patients examined, 109 (30.9%) patients had OME. Age of the participants ranged from 14 to 50 years; individuals between the ages of 14 and 22 years had the highest infection rates, while individuals between 40 and 50 years had the lowest rate of infection. Tympanic membrane perforation, fever, cough, sore throat, ear pain and hearing problem showed association with symptoms of OME. Microscopic analysis and biochemical characterization showed the presence of streptococci and staphylococci in all the studied samples. The most frequently isolated bacteria were Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus with percentage of 53.3%, 20% and 13.3% respectively. Enterococcus faecalis (6.6%) and Staphylococcus epidermidis (6.6%) were also identified in the studied samples. This study will help in the better medical administration of OME affected individuals.

Quantitative structure-property relationship modelling for predicting retention indices of essential oils based on an improved horse herd optimization algorithm.

The horse herd optimization algorithm (HOA), one of the more contemporary metaheuristic algorithms, has demonstrated superior performance in a number of challenging optimization tasks. In the present work, the descriptor selection issue is resolved by classifying different essential oil retention indices using the binary form, BHOA. Based on internal and external prediction criteria, Z-shape transfer functions (ZTF) were tested to verify their efficiency in improving BHOA performance in QSPR modelling for predicting retention indices of essential oils. The evaluation criteria involved the mean-squared error of the training and testing datasets (MSE), and leave-one-out internal and external validation (Q2). The degree of convergence of the proposed Z-shaped transfer functions was compared. In addition, K-fold cross validation with k = 5 was applied. The results show that ZTF, especially ZTF1, greatly improves the performance of the original BHOA. Comparatively speaking, ZTF, especially ZTF1, exhibits the fastest convergence behaviour of the binary algorithms. It chooses the fewest descriptors and requires the fewest iterations to achieve excellent prediction performance.

QSAR classification model for diverse series of antifungal agents based on binary coyote optimization algorithm.

One of the recently developed metaheuristic algorithms, the coyote optimization algorithm (COA), has shown to perform better in a number of difficult optimization tasks. The binary form, BCOA, is used in this study as a solution to the descriptor selection issue in classifying diverse antifungal series. Z-shape transfer functions (ZTF) are evaluated to verify their efficiency in improving BCOA performance in QSAR classification based on classification accuracy (CA), the geometric mean of sensitivity and specificity (G-mean), and the area under the curve (AUC). The Kruskal-Wallis test is also applied to show the statistical differences between the functions. The efficacy of the best suggested transfer function, ZTF4, is further assessed by comparing it to the most recent binary algorithms. The results prove that ZTF, especially ZTF4, significantly improves the performance of the original BCOA. The ZTF4 function yields the best CA and G-mean of 99.03% and 0.992%, respectively. It shows the fastest convergence behaviour compared to other binary algorithms. It takes the fewest iterations to reach high classification performance and selects the fewest descriptors. In conclusion, the obtained results indicate the ability of the ZTF4-based BCOA to find the smallest subset of descriptors while maintaining the best classification accuracy performance.