Visualizing vibrational normal modes of a single molecule with atomically confined light.

The internal vibrations of molecules drive the structural transformations that underpin chemistry and cellular function. While vibrational frequencies are measured by spectroscopy, the normal modes of motion are inferred through theory because their visualization would require microscopy with ångström-scale spatial resolution-nearly three orders of magnitude smaller than the diffraction limit in optics1. Using a metallic tip to focus light and taking advantage of the surface-enhanced Raman effect2 to amplify the signal from individual molecules, tip-enhanced Raman spectromicroscopy (TER-SM)3,4 reaches the requisite sub-molecular spatial resolution5, confirming that light can be confined in picocavities6-10 and anticipating the direct visualization of molecular vibrations11-13. Here, by using TER-SM at the precisely controllable junction of a cryogenic ultrahigh-vacuum scanning tunnelling microscope14-16, we show that ångström-scale resolution is attained at subatomic separation between the tip atom and a molecule in the quantum tunnelling regime of plasmons6,8,9,17. We record vibrational spectra within a single molecule, obtain images of normal modes and atomically parse the intramolecular charges and currents driven by vibrations. Our analysis provides a paradigm for optics in the atomistic near-field.

Development of a certified reference material for the accurate analysis of the acrylamide content in infant formula.

A certified reference material (CRM), KRISS CRM 108-02-006, was developed for the accurate analysis of low levels of acrylamide in infant formula matrices. The CRM is an infant formula fortified with acrylamide at a similar level as that stipulated by the European Union regulation for baby food. Commercially available infant formulas were processed by freeze-drying, and the subsequent homogenization of the fortified material to produce 961 bottles of the CRM in one batch. The CRM bottles containing approximately 15 g of the material in each unit were stored in a storage room at - 70 ℃. High-purity acrylamide was used as the primary reference material, and its purity was assessed using an in-house mass-balance method to obtain results metrologically traceable to the International System of Units. The acrylamide content of the infant formula CRM was evaluated using isotope dilution-liquid chromatography/mass spectrometry as a reference method, which was established by our research group. An acrylamide content of 55.7 ± 2.1 µg/kg was assigned as the certified value of the CRM with the expanded uncertainty at a 95% confidence level. The homogeneity study showed good uniformity of the acrylamide content among units, providing a relative standard deviation of 1.2% of the mean value. A stability study was also performed by monitoring the CRM under different temperature conditions and periods. The stability results indicated that the acrylamide content in the CRM under the storage conditions of - 70 ℃ remained stable for up to 10 months.

Establishment and application of bioassay- and molecular marker-based methods for monitoring fluvalinate resistance of Varroa mites.

The Varroa mite, Varroa destructor, is an ectoparasite that infests honey bees. The extensive use of acaricides, including fluvalinate, has led to the emergence of resistance in Varroa mite populations worldwide. This study's objective is to monitor fluvalinate resistance in field populations of Varroa mites in Korea through both bioassay-based and molecular marker-based methods. To achieve this, a residual contact vial (RCV) bioassay was established for on-site resistance monitoring. A diagnostic dose of 200 ppm was determined based on the bioassay using a putative susceptible population. In the RCV bioassay, early mortality evaluation was effective for accurately discriminating mites with the knockdown resistance (kdr) genotype, while late evaluation was useful for distinguishing mites with additional resistance factors. The RCV bioassay of 14 field mite populations collected in 2021 indicated potential resistance development in four populations. As an alternative approach, quantitative sequencing was employed to assess the frequency of the L925I/M mutation in the voltage-gated sodium channel (VGSC), associated with fluvalinate kdr trait. While the mutation was absent in 2020 Varroa mite populations, it emerged in 2021, increased in frequency in 2022, and became nearly widespread across the country by 2023. This recent emergence and rapid spread of fluvalinate resistance within a span of three years demonstrate the Varroa mite's significant potential for developing resistance. This situation further underscores the urgent need to replace fluvalinate with alternative acaricides. A few novel VGSC mutations potentially involved in resistance were identified. Potential factors driving the rapid expansion of resistance were further discussed.

Peroxisome Proliferator Activated Receptor-γ Agonistic Compounds from the Jellyfish-Derived Fungus Cladosporium oxysporum.

In our search for peroxisome proliferator-activated receptor (PPAR) agonists, five undescribed compounds, namely two acyclic diterpenes (1 and 2; cladopsol A and cladopsol B), two sesquiterpenes (3 and 4; cladopsol C and cladopsol D), and one C21-ecdysteroid (5; cladopsol E), and 15 known compounds were isolated from the jellyfish-derived fungus - Cladosporium oxysporum. The structures of the undescribed compounds were defined using UV, NMR, HR-ESI-MS, and electronic circular dichroism (ECD) spectroscopy and a modified Mosher's method. Luciferase reporter assay and docking analysis suggested that cladopsol B may function as a PPAR-γ partial agonist with a potential antidiabetic lead which may evade the side effects of full agonists. Moreover, cladopsol B stimulated glucose uptake in HepG2 cells with an efficacy comparable to that of rosiglitazone, but with less side effect induced by lipid accumulation in 3T3-L1 cells. Therefore, cladopsol B could serve as a molecular skeleton in a study of advanced antidiabetic lead with less side effect.

Peptidomimetic Wet-Adhesive PEGtides with Synergistic and Multimodal Hydrogen Bonding.

The remarkable underwater adhesion of mussel foot proteins has long been an inspiration in the design of peptidomimetic materials. Although the synergistic wet adhesion of catechol and lysine has been recently highlighted, the critical role of the polymeric backbone has remained largely underexplored. Here, we present a peptidomimetic approach using poly(ethylene glycol) (PEG) as a platform to evaluate the synergistic compositional relation between the key amino acid residues (i.e., DOPA and lysine), as well as the role of the polyether backbone in interfacial adhesive interactions. A series of PEG-based peptides (PEGtides) were synthesized using functional epoxide monomers corresponding to catechol and lysine via anionic ring-opening polymerization. Using a surface force apparatus, highly synergistic surface interactions among these PEGtides with respect to the relative compositional ratio were revealed. Furthermore, the critical role of the catechol-amine synergy and diverse hydrogen bonding within the PEGtides in the superior adhesive interactions was verified by molecular dynamics simulations. Our study sheds light on the design of peptidomimetic polymers with reduced complexity within the framework of a polyether backbone.

Myelination defects in the medial prefrontal cortex of Fkbp5 knockout mice.

The hypothalamic-pituitary-adrenal (HPA) axis plays a principal role in stress response regulation and has been implicated in the etiology of stress-related disorders. The HPA axis regulates the normal synthesis and release of glucocorticoids; dysregulation of the HPA axis causes abnormal responses to stress. FK506-binding protein 5 (FKBP5), a co-chaperone of heat shock protein 90 in the glucocorticoid receptor (GR) molecular complex, is a key GR sensitivity regulator. FKBP5 single nucleotide polymorphisms are associated with dysregulated HPA axis and increased risk of stress-related disorders, including posttraumatic stress disorder (PTSD) and depression. In this study, we profiled the microRNAs (miRNAs) in the medial prefrontal cortex of Fkbp5 knockout (Fkbp5-/- ) mice and identified the target genes of differentially expressed miRNAs using sequence-based miRNA target prediction. Gene ontology analysis revealed that the differentially expressed miRNAs were involved in nervous system development, regulation of cell migration, and intracellular signal transduction. The validation of the expression of predicted target genes using quantitative polymerase chain reaction revealed that the expression of axon development-related genes, specifically actin-binding LIM protein 1 (Ablim1), lemur tyrosine kinase 2 (Lmtk2), kinesin family member 5c (Kif5c), neurofascin (Nfasc), and ephrin type-A receptor 4 (Epha4), was significantly decreased, while that of brain-derived neurotrophic factor (Bdnf) was significantly increased in the brain of Fkbp5-/- mice. These results suggest that axonal development-related genes can serve as potential targets in future studies focused on understanding the pathophysiology of PTSD.

Selection of stable reference genes for quantitative real-time PCR in the Varroa mite, Varroa destructor.

To investigate the acaricide toxicity and resistance mechanisms in the Varroa mite, it is essential to understand the genetic responses of Varroa mites to acaricides, which are usually evaluated by transcriptional profiling based on quantitative real-time polymerase chain reaction (qPCR). In this study, to select reference genes showing consistent expression patterns regardless of the acaricide treatment or the type of tissue, Varroa mites treated with each of the three representative acaricides (coumaphos, fluvalinate, and amitraz) were processed for transcriptomic analysis, from which eight genes (NADH dehydrogenase [NADHD], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], eukaryotic translation elongation factor 1 α 1 [eEF1A1], eukaryotic translation elongation factor 2 [eEF2], ribosomal protein L5 [RpL5], Actin, tubulin α-1D chain [α-tubulin], and Rab1) were selected as candidates. The transcription profiles of these genes, depending on the treatment of the three acaricides or across different tissues (cuticle, legs, gut/fat bodies, and synganglion), were analyzed using qPCR with four validation programs, BestKeeper, geNorm, NormFinder, and RefFinder. Following acaricide treatment, eEF1A1 and NADHD showed the least variation in their expression levels, whereas the expression levels of α-tubulin and RpL5 were the most stable across different tissue groups. Rab1/GAPDH and Actin/eEF2 showed the least stable expression patterns following acaricide treatments and across different tissues, respectively, requiring precautions for use. When vitellogenin gene expression was analyzed by different reference genes, its expression profiles varied significantly depending on the reference genes, highlighting the importance of proper reference gene use. Thus, it is recommended using eEF1A1 and NADHD as reference genes for the comparison of the effects of acaricide on the whole body, whereas α-tubulin and RpL5 are recommended for investigating the tissue-specific expression profiles of target genes.

Molecular and kinetic properties of three acetylcholinesterases in the Varroa mite, Varroa destructor.

The Varroa mite, Varroa destructor, poses one of the most serious threats to honey bees worldwide. Although coumaphos, an anticholinesterase pesticide, is widely used for varroa mite control, little information is available on the properties of Varroa mite acetylcholinesterases (VdAChEs). In this study, three putative VdAChEs were annotated and named VdAChE1, VdAChE2, and VdAChE3. All VdAChEs possessed most of the functionally important signature domains, suggesting that they are catalytically active. Phylogenetic analysis revealed that VdAChE1 was clustered into a clade containing most arthropod AChE1s, whereas VdAChE2 and VdAChE3 formed a unique clade with other arachnid AChEs. VdAChE1 was determined to be membrane-anchored, but both VdAChE2 and VdAChE3 are soluble, as judged by electrophoresis in conjunction with western blotting. Tissue-specific transcription profiling revealed that VdAChE1 was most predominantly expressed in the synganglion. In contrast, VdAChE2 was most predominantly expressed in the legs and cuticle. VdAChE3 showed negligible expression levels in all the tissues examined. In a kinetic analysis using recombinant VdAChEs, VdAChE1 exhibited the highest catalytic efficiency, followed by VdAChE2 and VdAChE3. Inhibition experiments revealed that VdAChE1 was most sensitive to all tested inhibitors. Taken together, VdAChE1 appears to be the major synaptic enzyme with a more toxicological relevance, whereas VdAChE2 is involved in other noncatalytic functions, including chemical defense against xenobiotics. Current findings contribute to a more detailed understanding of the evolutionary and functional traits of VdAChEs and to the design of novel anticholinesterase varroacides.

Fraxinol Stimulates Melanogenesis in B16F10 Mouse Melanoma Cells through CREB/MITF Signaling.

Melanin pigment produced in melanocytes plays a protective role against ultraviolet radiation. Selective destruction of melanocytes causes chronic depigmentation conditions such as vitiligo, for which there are very few specific medical treatments. Here, we found that fraxinol, a natural coumarin from Fraxinus plants, effectively stimulated melanogenesis. Treatment of B16-F10 cells with fraxinol increased the melanin content and tyrosinase activity in a concentration-dependent manner without causing cytotoxicity. Additionally, fraxinol enhanced the mRNA expression of melanogenic enzymes such as tyrosinase, tyrosinase-related protein-1, and tyrosinase-related protein-2. Fraxinol also increased the expression of microphthalmia-associated transcription factor at both mRNA and protein levels. Fraxinol upregulated the phosphorylation of cyclic adenosine monophosphate (cAMP) response element-binding protein (CREB). Furthermore, H89, a cAMP-dependent protein kinase A inhibitor, decreased fraxinol-induced CREB phosphorylation and microphthalmia-associated transcription factor expression and significantly attenuated the fraxinol-induced melanin content and intracellular tyrosinase activity. These results suggest that fraxinol enhances melanogenesis via a protein kinase A-mediated mechanism, which may be useful for developing potent melanogenesis stimulators.

Dual-Modulated Release of a Cytotoxic Photosensitizer Using Photogenerated Reactive Oxygen Species and Glutathione.

Reversible thiol-disulfide exchange chemistry is of particular interest in drug delivery systems. However, high levels of glutathione (GSH) in cancer cells are hard to distinguish from GSH in normal cells, resulting in unmanageable cytotoxic drug release. This study investigates the spatiotemporally-controlled irreversible degradation of Ir-based photosensitizer (TIr3)-encapsulating nanogels (IrNG) through the hyperoxidation of resulting intracellular thiols using reactive oxygen species (ROS). A highly cytotoxic TIr3 was stably encapsulated within IrNG through hydrophobic interactions and reversible crosslinking between its disulfide bonds and thiols in the absence of light, resulting in high biocompatibility under normal cellular conditions. However, upon photoirradiation, TIr3 generated high levels of ROS, irreversibly oxidizing the thiols to induce electrostatic repulsion between the polymer molecules, resulting in the TIr3 release and induction of cancer cell apoptosis.

Quorum sensing-dependent post-secretional activation of extracellular proteases in Pseudomonas aeruginosa.

Pseudomonas aeruginosa secretes multiple proteases that are implicated in its pathogenesis, and most of them are regulated by quorum sensing (QS). In this study, we found that the activities of three major extracellular proteases, protease IV (PIV), elastase A (LasA), and elastase B (LasB), are reduced considerably when expressed in a QS mutant (MW1). PIV and LasA expressed in MW1 exhibited little activity, even when purified, and their activities were inhibited by noncleavage or binding of their propeptides. LasB was activated by a QS-dependent factor, indicating that, unlike what has been proposed previously, LasB is not autoactivated. When LasB was relieved from inhibition, it activated PIV, which then sequentially processed pro-LasA to mature LasA. When activated, LasB was not inhibited by exogenous addition of its propeptide, but LasA and PIV were inhibited by their propeptides, even after prior activation. These differences may be explained by the fact that LasB can degrade its own propeptide but PIV and LasA cannot. We also found that, although PIV is the preferred LasA-activating factor, LasB can also partially activate LasA. Overall, LasB, PIV, and LasA were activated postsecretionally in a cascading manner in which the initial activation of LasB was controlled tightly by QS at the protein level in addition to the well-known transcriptional control of these proteases by QS. Interestingly, human elastase also activated LasA, indicating that the activation cascade is triggered by host factors during infection. In summary, a QS-induced proteolytic cascade activates secreted proteases from P. aeruginosa.

Thermoregulation of Pseudomonas aeruginosa Biofilm Formation.

We investigated the effect of temperature on the biofilm formation of Pseudomonas aeruginosa and revealed that the biofilm formation increased rapidly at temperatures lower than 25°C. P. aeruginosa formed the most robust biofilm of a conspicuous mushroom-like structure at 20°C. However, when the temperature increased to 25°C, the biofilm formation rapidly decreased. Above 25°C, as the temperature rose, the biofilm formation increased again little by little despite its less-structured form, indicating that 25°C is the low point of biofilm formation. The intracellular 3',5'-cyclic diguanylate (c-di-GMP) levels also decreased rapidly as the temperature rose from 20 to 25°C. The expression levels of pelA, algD, and pslA encoding Pel, alginate, and Psl, respectively, were also dramatically affected by temperature, with pelA being regulated in a pattern similar to that of the intracellular c-di-GMP levels, and the pattern seen for algD regulation was the most similar to the actual biofilm formation pattern. Total exopolysaccharide production was thermoregulated and followed the regulation pattern of c-di-GMP. Interestingly, the thermoregulation patterns in biofilm formation were different depending on the strain of P. aeruginosa Unlike PAO1, another strain, PA14, showed a gradual decrease in biofilm formation and c-di-GMP in the range of 20 to 37°C, and P. aeruginosa clinical isolates also showed slightly different patterns in biofilm formation in conjunction with temperature change, suggesting that different strains may sense different temperature ranges for biofilm formation. However, it is obvious that P. aeruginosa forms more biofilms at lower temperatures and that temperature is an important factor in determining the biofilm formation.IMPORTANCE Biofilm formation is an important protection mechanism used by most microorganisms and provides cells with many advantages, like high infectivity, antibiotic resistance, and strong survivability. Since most persistent bacterial infections are believed to be associated with biofilms, biofilm control is an important issue in medicine, environmental engineering, and industry. Biofilm formation is influenced by various environmental factors. Temperature is the most direct environmental cue encountered by microorganisms. Here, we investigated the effect of temperature on the biofilm formation of P. aeruginosa, a notorious pathogen, and found that temperature is an important factor determining the amount and structure of biofilms. Low temperatures greatly increase biofilm formation and give biofilms a highly conspicuous structure. Although thermoregulation of biofilm formation is mainly mediated by c-di-GMP, some c-di-GMP-independent regulations were also observed. This study shows how biofilms are formed at various temperatures and provides new insights to control biofilms using temperature.

Predicting the Depth of the Lumbar Plexus in Pediatric Patients: A Retrospective Magnetic Resonance Imaging Study.

BACKGROUND: The lumbar plexus (LP) block is commonly used for analgesia for lower extremities. If the depth of the LP (LPD) can be predicted, the performance time and procedure-related complications could be reduced. METHODS: Three hundred sixty-one magnetic resonance images of pediatric patients (<18 years of age) were analyzed. Simple linear regression and multiple linear regression analyses were performed to predict the LPD using patient age, weight, height, and the distance between the midline and posterior superior iliac spine (midline-PSIS). The ratio of the distance between the midline and the most lateral aspect of the LP (midline-LP) to midline-PSIS (midline-LP/midline-PSIS ratio) was calculated to suggest a needle insertion point at the L4/L5 intervertebral level. The presence of the kidney at the L4 level and the L4/L5 intervertebral level was determined. RESULTS: The LPD at the L4/L5 intervertebral levels was predicted using the equation LPD = 0.844 × weight (kg) + 25.8 (mm) in pediatric patients <18 years of age (r = 0.791; 95% confidence interval [CI] of r, 0.753-0.829). The overall midline-LP/midline-PSIS ratio was 0.87 (95% CI, 0.86-0.89), and the ratio was higher in neonates and infants (0.98 [95% CI, 0.95-1.02]) than in the other age groups. The presence of the lower kidney pole at the L4 level was common in pediatric patients (43.7% of neonates and infants and 13.7% of toddlers and preschool-aged children). The lower kidney pole was observed at the L4/L5 level in 6 patients (1.7%). CONCLUSIONS: When LP block is performed in pediatric patients, the LPD and risk of renal injury should be considered for successful and safe analgesic block.

Investigating multidimensional characteristics of noise signals with tones from building mechanical systems and their effects on annoyance.

This paper investigates multidimensional characteristics of tonal noise from heating, ventilation, and air-conditioning systems, besides loudness and tonality, to improve prediction of annoyance. Two studies were conducted: multidimensional scaling (MDS) analysis to determine what other perceptual signal characteristics are important and perceptual weight analysis (PWA) to understand the impact of multiple tones in a signal. In the MDS study, paired comparison tasks were conducted to gather similarity and annoyance data. Results show that the latent perceptual dimensions are related to the signal's tonality, loudness, sharpness, and roughness. Including metrics for these perceptions, except roughness, improves the performance of earlier annoyance prediction models. Including both sharpness and tonal audibility does not further improve prediction performance, though. In the PWA study, noise stimuli with five-tone complexes between 125 Hz and 2 kHz were generated for subjective testing to obtain a perceptual weighting function. The levels of each tone were randomly adjusted for every trial, and both harmonic and inharmonic tone complexes were utilized. The PWA result was applied as a spectral weighting function to calculate a proposed weighted-sum tonal audibility metric. Utilizing the proposed metric instead of the traditional tonal audibility metric improves annoyance prediction to a similar degree as including sharpness.

Quantitative assessment of the pivot shift test with smartphone accelerometer.

PURPOSE: The pivot shift (PS) test is commonly used to diagnose and evaluate the dynamic instability of the knee joint in cases of anterior cruciate ligament (ACL) tear. There is a need of a reliable and inexpensive tool which is easily available to measure PS objectively in a clinical setting. The purpose of this study was to evaluate the use of a smartphone, which is readily available, to assess the PS phenomenon. METHODS: Seventeen patients with unilateral ACL-injured knees, undergoing ACL reconstruction, were enrolled in the study. PS was initially graded according to the International Knee Documentation Committee classification by two observers. The PS test was then performed by them in normal and injured knees under anaesthesia using a smartphone attached to Gerdy's tubercle. Acceleration changes during the PS test were recorded using the smartphone accelerometer application. Intra-observer and inter-observer reliability of the test among the two observers were evaluated. Acceleration changes were compared between the injured and normal knees, and also between the clinical grades of PS. Diagnostic utility of the smartphone accelerometer was examined by a receiver operating characteristic curve analysis. RESULTS: Intra-observer and inter-observer reliability were high for the smartphone accelerometer. The acceleration change was higher in the ACL-injured knees than in normal knees. The mean acceleration change was 2.54 m/s2 (SD = 0.97) in ACL-injured knees and 0.73 m/s2 (SD = 0.19) in normal knees (p < 0.001). The mean acceleration change of Grade 1 knees was 1.89 m/s2 (SD = 0.57), and that of knees of Grade 2 and above were 2.99 m/s2 (SD = 0.95) (p < 0.05). Sensitivity was 94% and specificity was 100% for the acceleration change required to detect ACL injury, i.e., 1.24 m/s2. CONCLUSIONS: The results show that a smartphone can be used to evaluate the PS quantitatively and reliably, in the diagnosis of ACL injury. LEVEL OF EVIDENCE: II.

C5, A Cassaine Diterpenoid Amine, Induces Apoptosis via the Extrinsic Pathways in Human Lung Cancer Cells and Human Lymphoma Cells.

Apoptosis pathways in cells are classified into two pathways: the extrinsic pathway, mediated by binding of the ligand to a death receptor and the intrinsic pathway, mediated by mitochondria. Apoptosis is regulated by various proteins such as Bcl-2 (B-cell lymphoma 2) family and cellular FLICE (Fas-associated Death Domain Protein Interleukin-1ß-converting enzyme)-inhibitory protein (c-FLIP), which have been reported to inhibit caspase-8 activity. In this study, it was found that C5 (3ß-Acetyl-nor-erythrophlamide), a compound of cassaine diterpene amine from Erythrophleum fordii, induced cell apoptosis in a variety of types of cancer cells. Induction of apoptosis in cancer cells by C5 was inversely related to the level of Bcl-2 expression. Overexpression of Bcl-2 into cancer cells significantly decreased C5-induced apoptosis. It was also found that treatment of cancer cells with a caspase-8 inhibitor significantly suppressed C5-induced apoptosis; however, treatment with caspase-9 inhibitors did not affect C5-induced apoptosis, suggesting that C5 may induce apoptosis via the extrinsic pathway by activating caspase-8. It was confirmed that treatment with C5 alone induced an association of FADD with procaspase-8; however, overexpression of c-FLIP decreased C5-induced caspase-8 activation. In conclusion, C5 could be utilized as a new useful lead compound for the development of an anti-cancer agent that has the goal of apoptosis.

Initial Evidence on the Impact of Performance-Based Treadmill Training on Pulmonary Function and Physical Performance in a Child with Bronchopulmonary Dysplasia: Single-Subject Experimental Study.

Aim: This study aimed to demonstrate the initial evidence on the impact of performance-based treadmill training on pulmonary function and physical performance of a patient with bronchopulmonary dysplasia (BPD).Methods: This study used a single-subject pre-experimental (A-B) research design (5 and 10 data points during the baseline and intervention phases, respectively) with a 4-month follow-up measurement. The subjects were a 5-year-old child diagnosed with bronchopulmonary dysplasia. Outcome measures were pulmonary function (forced vital capacity [FVC] and peak expiratory flow [PEF]) and physical performance (6-min walk test [6MWT], sit-to-stand test [STS], pediatric balance scale [PBS], and goal attainment scaling).Results: Applying the 2 standard deviation method, the FVC, PEF, 6MWT, and STS test scores showed significant improvement compared to baseline values. In addition, the PBS and goal attainment scaling scores improved by 5.36% (42 points to 45 points) and 29.61% (37.6 points to 59.75 points) after the intervention, respectively. Gains were maintained at the 4-month follow-up.Conclusions: These findings suggest that performance-based treadmill training may be a possible treatment option to improve the pulmonary function and physical performance of children with BPD. Further rigorous studies are needed to establish evidence regarding the effectiveness of the training program among this population.

The investigation of combined ventilation-biofilter systems using recycled treated wastewater on odor reduction efficiency.

OBJECTIVE: The present study aimed to evaluate the performance of odor abatement by using two different ventilation-biofilter systems with recycled stablized swine wastewater. METHODS: The performance of odor removal efficiency was evaluated using two different ventilation-biofilter-recycled wastewater arrangements. A recirculating air-flow ventilation system connected to a vertical biofilter (M1) and a plug-flow ventilation system connected to a horizontal biofilter (M2) were installed. Water dripping over the surface of the biofilter was recycled at a flow rate of 0.83 L/h in summer and 0.58 L/h in winter to reduce odorous compounds and particulate matter (PM). The experiments were performed for 64 days with M1 and M2 to investigate how these two ventilation-biofilter systems influenced the reduction of odor compounds in the model houses. Odorous compounds, NH3 and volatile organic compounds (VOCs) were analyzed, and microclimatic variables such as temperature, humidity, and PM were monitored. RESULTS: Ammonia concentration inside M1 was about 41% higher on average than that in M2. PM and total suspended particles (TSPs) inside M1 were about 62.2% and 69.9%, respectively, higher than those in M2. TSPs in the model house were positively correlated with the concentration of NH3 and VOCs. CONCLUSION: M2 emitted lower concentration of odorous compounds than M1. Moreover, M2 could maintain the optimum temperature condition for a swine house during the cooler season. The plug-flow ventilation-horizontal biofilter system could be used for pig houses to minimize air pollution produced by swine farming activities and maintain optimum microclimate conditions for pigs.

Lumbosacral and thoracolumbosacral cerebrospinal fluid volume changes in neonates, infants, children, and adolescents: A retrospective magnetic resonance imaging study.

BACKGROUND: The volume of cerebrospinal fluid can affect the pharmacokinetics and pharmacodynamics of local anesthetics for spinal anesthesia and other intrathecal medications. AIMS: The objective of this study was to estimate the lumbosacral cerebrospinal fluid volume and thoracolumbosacral cerebrospinal fluid volume using magnetic resonance images in pediatric patients from neonates and infants to adolescents. METHODS: Spinal magnetic resonance images of 500 pediatric patients (age <18 years) were reviewed. The lumbosacral cerebrospinal fluid volumes of 418 patients and thoracolumbosacral cerebrospinal fluid volumes of 248 patients were measured. The relationship between cerebrospinal fluid volumes and age, height, and weight were evaluated. The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes per weight were calculated to elucidate developmental changes. RESULTS: The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes showed linear correlations with height (r2  = 0.730 and r2  = 0.661, respectively), whereas they showed curvilinear correlations with age (r2  = 0.752 and r2  = 0.717, respectively) and weight (r2  = 0.734 and r2  = 0.734, respectively). The mean lumbosacral cerebrospinal fluid volume per weight (mL/kg) was 0.85 (standard deviation [SD]: 0.19, 95% confidence interval [CI]: 0.81-0.90) in neonates and infants, 0.86 (SD: 0.22, 95% CI: 0.83-0.89) in toddlers and preschoolers, 0.71 (SD: 0.26, 95% CI: 0.66-0.76) in schoolers, and 0.54 (SD: 0.20, 95% CI: 0.49-0.60) in adolescents. The mean thoracolumbosacral cerebrospinal fluid volume per weight (mL/kg) was 1.95 (SD: 0.37, 95% CI: 1.86-2.04) in neonates and infants, 1.82 (SD: 0.41, 95% CI: 1.75-1.88) in toddlers and preschoolers, 1.38 (SD: 0.40, 95% CI: 1.23-1.52) in schoolers, and 0.99 (SD: 0.34, 95% CI: 0.45-1.53) in adolescents. CONCLUSION: The lumbosacral and thoracolumbosacral cerebrospinal fluid volumes in pediatric patients were much smaller than previously presented values, showing linear correlations with height, and demonstrate curvilinear correlations with age and weight.

Bacterial ornithine lipid, a surrogate membrane lipid under phosphate-limiting conditions, plays important roles in bacterial persistence and interaction with host.

Ornithine lipids (OLs) are bacteria-specific lipids that are found in the outer membrane of Gram (-) bacteria and increase as surrogates of phospholipids under phosphate-limited environmental conditions. We investigated the effects of OL increase in bacterial membranes on pathogen virulence and the host immune response. In Pseudomonas aeruginosa, we increased OL levels in membranes by overexpressing the OL-synthesizing operon (olsBA). These increases changed the bacterial surface charge and hydrophobicity, which reduced bacterial susceptibility to antibiotics and antimicrobial peptides (AMPs), interfered with the binding of macrophages to bacterial cells and enhanced bacterial biofilm formation. When grown under low phosphate conditions, P. aeruginosa became more persistent in the treatment of antibiotics and AMPs in an olsBA-dependent manner. While OLs increased persistence, they attenuated P. aeruginosa virulence; in host cells, they reduced the production of inflammatory factors (iNOS, COX-2, PGE2 and nitric oxide) and increased intracellular Ca2+ release. Exogenously added OL had similar effects on P. aeruginosa and host cells. Our results suggest that bacterial OL plays important roles in bacteria-host interaction in a way that enhances bacterial persistence and develops chronic adaptation to infection.