Miracle-dz/UniFAR-FTUs huggingface dataset:
Inactivation of DltA Modulates Virulence Factor Expression in Streptococcus pyogenes

Background D-alanylated lipoteichoic acid is a virtually ubiquitous component of Gram-positive cell walls. Mutations in the dltABCD operon of numerous species exhibit pleiotropic effects, including reduced virulence, which has been attributed to increased binding of cationic antimicrobial peptides to the more negatively charged cell surface. In this study, we have further investigated the effects that mutating dltA has on virulence factor expression in Streptococcus pyogenes. Methodology/Principal Findings Isogenic ΔdltA mutants had previously been created in two distinct M1T1 isolates of S. pyogenes. Immunoblots, flow cytometry, and immunofluorescence were used to quantitate M protein levels in these strains, as well as to assess their ability to bind complement. Bacteria were tested for their ability to interact with human PMN and to grow in whole human blood. Message levels for emm, sic, and various regulatory elements were assessed by quantitative RT-PCR. Cell walls of ΔdltA mutants contained much less M protein than cell walls of parent strains and this correlated with reduced levels of emm transcripts, increased deposition of complement, increased association of bacteria with polymorphonuclear leukocytes, and reduced bacterial growth in whole human blood. Transcription of at least one other gene of the mga regulon, sic, which encodes a protein that inactivates antimicrobial peptides, was also dramatically reduced in ΔdltA mutants. Concomitantly, ccpA and rofA were unaffected, while rgg and arcA were up-regulated. Conclusions/Significance This study has identified a novel mechanism for the reduced virulence of dltA mutants of Streptococcus pyogenes in which gene regulatory networks somehow sense and respond to the loss of DltA and lack of D-alanine esterification of lipoteichoic acid. The mechanism remains to be determined, but the data indicate that the status of D-alanine-lipoteichoic acid can significantly influence the expression of at least some streptococcal virulence factors and provide further impetus to targeting the dlt operon of Gram-positive pathogens in the search for novel antimicrobial compounds.
Expectations and outcomes in cataract surgery: a prospective test of 2 models of satisfaction.

OBJECTIVES To document patients' preoperative expectations for postoperative outcomes. To measure the relative contribution of patient understanding, expectations, outcome, and expectation-outcome discrepancy in determining patient satisfaction. METHODS One hundred twenty-one patients were surveyed just before and 1 month after cataract surgery regarding their understanding of the procedure, satisfaction with their vision, and both current and expected visual function for each of the items on the Visual Function Index (VF-14). RESULTS Sixty percent of patients expected to achieve a perfect VF-14 score. The average expected VF-14 score was 96.1, compared with an achieved VF-14 score of just 89.8. The most unrealistic expectations involved driving at night, reading small print, and doing fine handiwork. Surprisingly, improvement in visual function was not correlated with satisfaction in vision. While patient understanding, expectations, and achieved VF-14 score did correlate with satisfaction, when controlling for other factors, only achievement-expectation discrepancy was independently predictive. CONCLUSIONS This study provides support for the expectation-outcome discrepancy model of patient satisfaction. Further, it highlights the highly unrealistic expectations harbored by patients with cataract and emphasizes the importance for physicians to control their patients' expectations. Controlling patient expectations may be more effective than improving patients' postoperative outcome in terms of maximizing patient satisfaction.
A Three-Dimensional Finite Element Analysis of Restored Deciduous Canine

The literature reports that dental cavities are an international public health challenge and treatment of decays especially for young children is a medical problem of great importance. Early childhood caries progress rapidly and can cause functional, physical and dentofacial aesthetic impairment. Recent studies show that caries lesions can compromise children’s quality of life due to the pain and discomfort which could lead to disfigurement, acute and chronic infections and to alteration of meals and sleeping habits. Tooth decay occurs when acids in the mouth dissolve the outer layers of the tooth, stripping the tooth of important minerals. Because dental decay often goes untreated, the cavity grows and more tooth structure is lost. Restorative dentistry has the main purpose of rehabilitating the function and aesthetic of tooth. The structural integrity of the restored teeth depends on the state of stress in their different regions due to occlusal loads. The aim of this study performed with the finite element method is to evaluate the stress and strain distributions in bone structure-primary canine-restorative material assembly when a load of 120N is applied all over the upper surface of the model. Particular attention was given to an accurate computer reconstruction of the canine. Therefore with the aid of a CT scanner the tomography images obtained were processed with a special software (Mimics). Two dental restorative materials, commonly used in practice were chosen for the analysis and the results acquired are compared. Also the contact pressure at the interface bone-deciduous canine and deciduous canine-dental material is evaluated in both cases.
Effects of Plasma Membrane Cholesterol Level and Cytoskeleton F-Actin on Cell Protrusion Mechanics

Protrusions are deformations that form at the surface of living cells during biological activities such as cell migration. Using combined optical tweezers and fluorescent microscopy, we quantified the mechanical properties of protrusions in adherent human embryonic kidney cells in response to application of an external force at the cell surface. The mechanical properties of protrusions were analyzed by obtaining the associated force-length plots during protrusion formation, and force relaxation at constant length. Protrusion mechanics were interpretable by a standard linear solid (Kelvin) model, consisting of two stiffness parameters, k 0 and k 1 (with k 0>k 1), and a viscous coefficient. While both stiffness parameters contribute to the time-dependant mechanical behavior of the protrusions, k 0 and k 1 in particular dominated the early and late stages of the protrusion formation and elongation process, respectively. Lowering the membrane cholesterol content by 25% increased the k 0 stiffness by 74%, and shortened the protrusion length by almost half. Enhancement of membrane cholesterol content by nearly two-fold increased the protrusion length by 30%, and decreased the k 0 stiffness by nearly two-and-half-fold as compared with control cells. Cytoskeleton integrity was found to make a major contribution to protrusion mechanics as evidenced by the effects of F-actin disruption on the resulting mechanical parameters. Viscoelastic behavior of protrusions was further characterized by hysteresis and force relaxation after formation. The results of this study elucidate the coordination of plasma membrane composition and cytoskeleton during protrusion formation.
The role of melatonin in anaesthesia and critical care

Melatonin is a neurohormone secreted by the pineal gland. It is widely present in both plant and animal sources. In several countries, it is sold over the counter as tablets and as food supplement or additive. Currently, it is most often used to prevent jet lag and to induce sleep. It has been and is being used in several clinical trials with different therapeutic approaches. It has sedative, analgesic, anti-inflammatory, anti-oxidative and chronobiotic effects. In the present review, the potential therapeutic benefits of melatonin in anaesthesia and critical care are presented. This article aims to review the physiological properties of melatonin and how these could prove useful for several clinical applications in perioperative management, critical care and pain medicine. The topic was handsearched from textbooks and journals and electronically from PubMed, and Google scholar using text words.
Backward machine transliteration by learning phonetic similarity

In many cross-lingual applications we need to convert a transliterated word into its original word. In this paper, we present a similarity-based framework to model the task of backward transliteration, and provide a learning algorithm to automatically acquire phonetic similarities from a corpus. The learning algorithm is based on Widrow-Hoff rule with some modifications. The experiment results show that the learning algorithm converges quickly, and the method using acquired phonetic similarities remarkably outperforms previous methods using pre-defined phonetic similarities or graphic similarities in a corpus of 1574 pairs of English names and transliterated Chinese names. The learning algorithm does not assume any underlying phonological structures or rules, and can be extended to other language pairs once a training corpus and a pronouncing dictionary are available.
Anesthetic management with sevoflurane combined with alfaxalone-medetomidine constant rate infusion in a Thoroughbred racehorse undergoing a long-time orthopedic surgery

ABSTRACT A three-year old Thoroughbred racehorse was anesthetized with sevoflurane and oxygen inhalation anesthesia combined with constant rate infusion (CRI) of alfaxalone-medetomidine for internal fixation of a third metacarpal bone fracture. After premedication with intravenous (IV) injections of medetomidine (6.0 µg/kg IV), butorphanol (25 µg/kg IV), and midazolam (20 µg/kg IV), anesthesia was induced with 5% guaifenesin (500 ml/head IV) followed immediately by alfaxalone (1.0 mg/kg IV). Anesthesia was maintained with sevoflurane and CRIs of alfaxalone (1.0 mg/kg/hr) and medetomidine (3.0 µg/kg/hr). The total surgical time was 180 min, and the total inhalation anesthesia time was 230 min. The average end-tidal sevoflurane concentration during surgery was 1.8%. The mean arterial blood pressure was maintained above 70 mmHg throughout anesthesia, and the recovery time was 65 min. In conclusion, this anesthetic technique may be clinically applicable for Thoroughbred racehorses undergoing a long-time orthopedic surgery.
Short-term effect of ozone on the pulmonary function of children in primary school.

The objective of this study was to evaluate the short-term effect of ambient air pollution on the pulmonary function of schoolchildren. We sampled 941 children in primary school in three communities in Taiwan (Sanchun, Taihsi, and Linyuan). The nearby stations of the Taiwan air quality monitoring network provided the hourly ambient concentrations of sulfur dioxide, carbon monoxide, ozone, particulate matter < or = to 10 microm in aerodynamic diameter, and nitrogen dioxide. Spirometry was performed once for each sampled child. We also obtained the status of indoor air pollution and chronic respiratory disease history by using a structured questionnaire. Multivariate linear model analysis was used to evaluate pulmonary function effects of each pollutant in addition to determinants of indoor air pollution and meteorologic conditions. We found a significantly negative association of peak O(3) concentration on the day before spirometry with individual forced vital capacity and forced expiratory volume in 1 sec. The decrease in children's lung function can occur at peak hourly O(3) concentrations < 80 ppb. The slope of lung function decrease for Taiwanese children is approximately 1 mL/ppb for peak hourly O(3) exposure. ImagesFigure 1Figure 2
Antibacterial cotton fabric with in situ generated silver nanoparticles by one-step hydrothermal method

ABSTRACT The cotton fabrics were immersed in 1–5 mM aqueous silver nitrate solutions maintained at 80°C for 24 h to in situ generate silver nanoparticles. The presence of silver nanoparticles in the nanocomposite films was proved by microscopic observation. Fourier transform infrared spectra indicated the role of hydroxyl and carboxyl groups of cotton fabric in reducing the silver salt to nanosilver. The nanocomposite cotton fabrics showed good antibacterial activity against Gram-negative and Gram-positive bacteria. The antibacterial cotton fabrics can be considered for medical applications such as surgical aprons, wound cleaning, and dressing.
Capture of Neuroepithelial-Like Stem Cells from Pluripotent Stem Cells Provides a Versatile System for In Vitro Production of Human Neurons

Human embryonic stem cells (hESC) and induced pluripotent stem cells (iPSC) provide new prospects for studying human neurodevelopment and modeling neurological disease. In particular, iPSC-derived neural cells permit a direct comparison of disease-relevant molecular pathways in neurons and glia derived from patients and healthy individuals. A prerequisite for such comparative studies are robust protocols that efficiently yield standardized populations of neural cell types. Here we show that long-term self-renewing neuroepithelial-like stem cells (lt-NES cells) derived from 3 hESC and 6 iPSC lines in two independent laboratories exhibit consistent characteristics including i) continuous expandability in the presence of FGF2 and EGF; ii) stable neuronal and glial differentiation competence; iii) characteristic transcription factor profile; iv) hindbrain specification amenable to regional patterning; v) capacity to generate functionally mature human neurons. We further show that lt-NES cells are developmentally distinct from fetal tissue-derived radial glia-like stem cells. We propose that lt-NES cells provide an interesting tool for studying human neurodevelopment and may serve as a standard system to facilitate comparative analyses of hESC and hiPSC-derived neural cells from control and diseased genetic backgrounds.
Is ageing hard? A study of aged RO membranes and their integrity to remove virus surrogates

One of the major membrane technology applications is the production of high quality water by removing organic and inorganic contaminants. Reverse osmosis (RO) technology is the most efficient separation approach. Due to their high removal efficiency and the chemistry of the barrier layer, RO membranes become fouled over time which leads to significant negative impact on their performances and the operational cost. In order to limit biofouling, organic fouling and scaling, water treatment plants mostly use pre-treatment, antiscalants, monochloramine, acid and base chemical cleaning to prevent or to remove fouling. Up-todate, the impact of these chemical treatments on the integrity of the polyamide membrane is not well understood, especially regarding the impact on the virus removal efficiency. In the past, the virus removal efficiency of RO membranes has been monitored by measuring electrical conductivity, MS2 phage, rhodamine-WT (R-WT) or sulphate. Henderson et al [1] suggested the use of dissolved organic matter (DOM) for this purpose. Thus, the objective of our study was to determine the impact of aged membrane on virus rejection using five virus surrogates having different properties: electrical conductivity, sulphate, R-WT, DOM and MS2 phage.
Clemastine rescues myelination defects and promotes functional recovery in hypoxic brain injury

Hypoxia can injure brain white matter tracts, comprised of axons and myelinating oligodendrocytes, leading to cerebral palsy in neonates and delayed post-hypoxic leukoencephalopathy (DPHL) in adults. In these conditions, white matter injury can be followed by myelin regeneration, but myelination often fails and is a significant contributor to fixed demyelinated lesions, with ensuing permanent neurological injury. Non-myelinating oligodendrocyte precursor cells are often found in lesions in plentiful numbers, but fail to mature, suggesting oligodendrocyte precursor cell differentiation arrest as a critical contributor to failed myelination in hypoxia. We report a case of an adult patient who developed the rare condition DPHL and made a nearly complete recovery in the setting of treatment with clemastine, a widely available antihistamine that in preclinical models promotes oligodendrocyte precursor cell differentiation. This suggested possible therapeutic benefit in the more clinically prevalent hypoxic injury of newborns, and we demonstrate in murine neonatal hypoxic injury that clemastine dramatically promotes oligodendrocyte precursor cell differentiation, myelination, and improves functional recovery. We show that its effect in hypoxia is oligodendroglial specific via an effect on the M1 muscarinic receptor on oligodendrocyte precursor cells. We propose clemastine as a potential therapy for hypoxic brain injuries associated with white matter injury and oligodendrocyte precursor cell maturation arrest.
Automated embolic signal detection using Deep Convolutional Neural Network

This work investigated the potential of Deep Neural Network in detection of cerebral embolic signal (ES) from transcranial Doppler ultrasound (TCD). The resulting system is aimed to couple with TCD devices in diagnosing a risk of stroke in real-time with high accuracy. The Adaptive Gain Control (AGC) approach developed in our previous study is employed to capture suspected ESs in real-time. By using spectrograms of the same TCD signal dataset as that of our previous work as inputs and the same experimental setup, Deep Convolutional Neural Network (CNN), which can learn features while training, was investigated for its ability to bypass the traditional handcrafted feature extraction and selection process. Extracted feature vectors from the suspected ESs are later determined whether they are of an ES, artifact (AF) or normal (NR) interval. The effectiveness of the developed system was evaluated over 19 subjects going under procedures generating emboli. The CNN-based system could achieve in average of 83.0% sensitivity, 80.1% specificity, and 81.4% accuracy, with considerably much less time consumption in development. The certainly growing set of training samples and computational resources will contribute to high performance. Besides having potential use in various clinical ES monitoring settings, continuation of this promising study will benefit developments of wearable applications by leveraging learnable features to serve demographic differentials.
Treatment of sudden sensorineural hearing loss: I. A systematic review.

OBJECTIVE To identify, evaluate, and review randomized controlled trials (RCTs) on the treatment of sudden sensorineural hearing loss (SSHL). DATA SOURCES A MEDLINE search and hand search were conducted to identify RCTs published between January 1966 and February 2006 in the English language on the treatment of SSHL. Search terms included hearing loss, sensorineural (MeSH term), sensorineural hearing loss (text words), and sudden deafness (text words). STUDY SELECTION Prospective RCTs on the treatment of patients diagnosed as having SSHL. DATA EXTRACTION One independent observer extracted study data. Validity was evaluated using standard criteria. Characteristics and results were reviewed systematically. DATA SYNTHESIS A total of 21 RCTs were identified regarding various treatments, including systemic and intratympanic steroids; antiviral and hemodilution agents; mineral, vitamin, and herbal preparations; batroxobin; carbogen; and hyperbaric oxygen. All studies used audiometric outcome measures. Only 2 studies used identical criteria to define SSHL. The method of randomization was described in 2 studies. Validity scores ranged from 2 to 8 (of 9). Positive results were reported favoring systemic steroids, intratympanic steroids, batroxobin, magnesium, vitamin E, and hyperbaric oxygen, although there were serious limitations in each study with a positive finding. There was no difference in audiometric outcomes reported across all studies of antiviral and hemodilution agents and no difference in one study of systemic steroids vs placebo. CONCLUSIONS To our knowledge, no valid RCT exists to determine effective treatment of SSHL. Systemic steroids cannot be considered the gold standard of treatment of SSHL, given the severe limitations of the landmark study supporting their use.
Formation of the Giardia Cyst Wall: Studies on Extracellular Assembly Using Immunogold Labeling and High Resolution Field Emission SEM

Encystment of the intestinal protozoan, Giardia, is a key step in the life cycle that enables this parasite to be transmitted from host to host via either fecal oral, waterborne, or foodborne transmission. The process of encystment was studied by localizing cyst wall specific antigens with immunofluorescence for light microscopy and immunogold staining for field emission scanning electron microscopy. Chronological sampling of Giardia cultures stimulated with endogenous bile permitted identification of an intracellular and extracellular phase in cyst wall formation, a process which required a total of 14‐16 h. The intracellular phase lasted for 8‐10 h, while the extracellular phase, involved the appearance of cyst wall antigen on the trophozoite membrane, and the assembly of the filamentous layer, a process requiring an additional 4‐6 h for completion of mature cysts. The extracellular phase was initiated with the appearance of cyst wall antigen on small protrusions of the trophozoite membrane (‐15 nm), which became enlarged with time to caplike structures ranging up to 100 nm in diameter. Caplike structures involved with filament growth were detected over the entire surface of the trophozoite including the adhesive disc and flagella. Encysting cells rounded up, lost attachment to the substratum, and became enclosed in a layer of filaments. Late stages in encystment included a “tailed” cyst in which flagella were not fully retracted into the cyst. Clusters of cysts were seen in which filaments at the surface of one cyst were connected with the surface of adjacent cysts or the “tailed” processes of adjacent cysts, suggesting that the growth of cyst wall filaments may be at the terminal end. In conclusion, the process of encystment has been shown to consist of two morphologically different stages (intracellular and extracellular) which requires 16 h for completion. Further investigation of the extracellular stage with regard to assembly of the filamentous layer of the cyst wall may lead to innovative methods for interfering with production of an intact functional cyst wall, and thereby, regulation of viable Giardia cyst release from the host.