An extract of the Chinese herbal root kudzu reduces alcohol drinking by heavy drinkers in a naturalistic setting

BACKGROUND: Of the available medications for treating alcohol-related problems, none are universally effective, and all have side effects that may limit their use. Extracts of kudzu containing a variety of isoflavones have been shown to reduce alcohol drinking in rats and hamsters. METHODS: The present study was designed to test the efficacy of a kudzu extract in a clinical population. Male and female "heavy" alcohol drinkers were treated with either placebo or a kudzu extract for 7 days and then given an opportunity to drink their preferred brand of beer while in a naturalistic laboratory setting. Participants served as their own controls, and order of treatment exposure was counterbalanced. Drinking behavior was monitored by a digital scale that was located in the top of an end table. RESULTS: Kudzu treatment resulted in significant reduction in the number of beers consumed that was paralleled by an increase in the number of sips and the time to consume each beer and a decrease in the volume of each sip. These changes occurred in the absence of a significant effect on the urge to drink alcohol. There were no reported side effects of kudzu treatment. CONCLUSION: These data suggest that an extract of this leguminous plant may be a useful adjunct in reducing alcohol intake in a naturalistic setting.     

Can We Reduce Negative Blood Cultures With Clinical Scores and Blood Markers? Results From an Observational Cohort Study

Only a small proportion of blood cultures routinely performed in emergency department (ED) patients is positive. Multiple clinical scores and biomarkers have previously been examined for their ability to predict bacteremia. Conclusive clinical validation of these scores and biomarkers is essential.This observational cohort study included patients with suspected infection who had blood culture sampling at ED admission. We assessed 5 clinical scores and admission concentrations of procalcitonin (PCT), C-reactive protein (CRP), lymphocyte and white blood cell counts, the neutrophil-lymphocyte count ratio (NLCR), and the red blood cell distribution width (RDW). Two independent physicians assessed true blood culture positivity. We used logistic regression models with area under the curve (AUC) analysis.Of 1083 patients, 104 (9.6%) had positive blood cultures. Of the clinical scores, the Shapiro score performed best (AUC 0.729). The best biomarkers were PCT (AUC 0.803) and NLCR (AUC 0.700). Combining the Shapiro score with PCT levels significantly increased the AUC to 0.827. Limiting blood cultures only to patients with either a Shapiro score of ≥4 or PCT > 0.1 μg/L would reduce negative sampling by 20.2% while still identifying 100% of positive cultures. Similarly, a Shapiro score ≥3 or PCT >0.25 μg/L would reduce cultures by 41.7% and still identify 96.1% of positive blood cultures.Combination of the Shapiro score with admission levels of PCT can help reduce unnecessary blood cultures with minimal false negative rates.The study was registered on January 9, 2013 at the ‘ClinicalTrials.gov’ registration web site ({"type":"clinical-trial","attrs":{"text":"NCT01768494","term_id":"NCT01768494"}}NCT01768494).     

Glycan modulation and sulfoengineering of anti–HIV-1 monoclonal antibody PG9 in plants

Broadly neutralizing anti–HIV-1 monoclonal antibodies, such as PG9, and its derivative RSH hold great promise in AIDS therapy and prevention. An important feature related to the exceptional efficacy of PG9 and RSH is the presence of sulfated tyrosine residues in their antigen-binding regions. To maximize antibody functionalities, we have now produced glycan-optimized, fucose-free versions of PG9 and RSH in Nicotiana benthamiana. Both antibodies were efficiently sulfated in planta on coexpression of an engineered human tyrosylprotein sulfotransferase, resulting in antigen-binding and virus neutralization activities equivalent to PG9 synthesized by mammalian cells (^CHOPG9). Based on the controlled production of both sulfated and nonsulfated variants in plants, we could unequivocally prove that tyrosine sulfation is critical for the potency of PG9 and RSH. Moreover, the fucose-free antibodies generated in N. benthamiana are capable of inducing antibody-dependent cellular cytotoxicity, an activity not observed for ^CHOPG9. Thus, tailoring of the antigen-binding site combined with glycan modulation and sulfoengineering yielded plant-produced anti–HIV-1 antibodies with effector functions superior to PG9 made in CHO cells.Monoclonal antibodies (mAbs) offer great promise for AIDS treatment (1). In particular, the recent discovery of broadly neutralizing anti–HIV-1 mAbs (bNAbs) with extraordinary potency as exemplified by the antibodies PG9, PG16 (2), or those of the PGT series (3) creates hope for effective therapy by passive antibody transfer. PG9 and its close relative PG16 neutralize ∼80% of HIV-1 isolates across all clades (2, 4). The recognized epitopes are within the hypervariable and heavily glycosylated V1/V2 loops of the viral envelope glycoprotein gp120 and preferentially displayed in its trimeric state (2). Both mAbs use their unusually long complementarity-determining region (CDR) H3 domains (4–6) to penetrate the glycan shield of the virus and make contact with the underlying protein backbone (7). In addition, PG9 and PG16 recognize two highly conserved gp120 N-glycans attached to Asn¹⁶⁰ and Asn^156/173, which flank the peptide epitope (7–9). Remarkably, the glycan-binding properties of the two antibodies could be combined by modification of the PG9 light chain with R^L94SH^L95A as found in PG16. This PG9 variant (here termed RSH) has a superior neutralization capacity and broader coverage of HIV-1 isolates than either wild-type PG9 or PG16, which makes it an excellent choice for additional drug development studies (7).Proper N-glycosylation is important for aspects of mAb functionality, because the oligosaccharides attached to Asn²⁹⁷ of the crystallizable fragment (Fc) are known to strongly affect binding to cellular Fc receptors and thus, in vivo functionalities (10). In particular, core α1,6-fucosylation, typically found on mAbs produced in mammalian cell lines, has been shown to hinder antibody-dependent, cell-mediated cytotoxicity (ADCC) and antibody-dependent, cell-mediated virus inactivation (11), key effector functions in the context of anti–HIV-1 immune responses (12–14). Hence, considerable efforts have been undertaken to establish mAb production systems generating human-type N-glycans lacking this modification. Plants, particularly Nicotiana benthamiana, are well-suited for glycan engineering processes. The advantages of plant-based expression platforms include a high extent of glycan homogeneity, the flexibility with which glycosylation can be modulated, high production speed, and ease of large-scale production (15). The superior efficiency of glycocengineered mAbs produced in plants has recently been highlighted by ZMapp, an mAb mixture developed for the treatment of Ebola patients (16). Similarly, improved effector potency has been observed for plant-made anti–HIV-1 bNAb 2G12 (17), rendering glycoengineered plants an interesting production system for mAbs.Another posttranslational modification, namely tyrosine sulfation of selected residues in the CDR H3 region of PG9 and PG16, has recently been shown to be critical for high-affinity interactions with their antigen (4, 6). In humans, tyrosine sulfation is carried out by two closely related type II transmembrane proteins: tyrosylprotein sulfotransferase 1 (TPST1) and TPST2 (reviewed in refs. 18 and 19). Although plants contain TPSTs, these proteins are phylogenetically unrelated to the human enzymes and could, therefore, exhibit different enzymatic properties (18, 20). Previous attempts to produce bioactive PG9 and PG16 in N. benthamiana have failed, possibly because of deficient tyrosine sulfation (21). Hence, it is currently uncertain whether plant-based expression platforms are naturally capable of sulfating tyrosine residues in recombinant proteins.Here, we aimed to maximize the potency of bNAbs against HIV-1 using a plant-based expression system. For this goal, PG9 and RSH were expressed in a xylosyltransferase (XT)- and fucosyltransferase (FT)-deficient N. benthamiana mutant (ΔXT/FT) supporting the synthesis of glycan-optimized, fucose-free mAbs (15). Whereas tyrosine sulfation of PG9 by endogenous plant enzymes was barely detectable, this additional posttranslational modification was efficiently introduced by coexpression of human TPST1 (hsTPST1) modified with a plant Golgi-targeting sequence. When sulfated, plant-derived PG9 had essentially the same antigen-binding and virus neutralization properties as its counterpart produced in CHO cells. Importantly, ADCC activity was displayed by fucose-free, plant-produced mAbs but not by CHO-derived PG9. Furthermore, the controlled production of both sulfated and unmodified PG9 in the same expression system enabled us to establish the impact of tyrosine sulfation on the functionality of this important bNAb.     

The Composites of Graphene Oxide with Metal or Semimetal Nanoparticles and Their Effect on Pathogenic Microorganisms

The present experiment describes a synthesis process of composites based on graphene oxide, which was tested as a carrier for composites of metal- or metalloid-based nanoparticles (Cu, Zn, Mn, Ag, AgP, Se) and subsequently examined as an antimicrobial agent for some bacterial strains (Staphylococcus aureus (S. aureus), methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). The composites were first applied at a concentration of 300 µM on all types of model organisms and their effect was observed by spectrophotometric analysis, which showed a decrease in absorbance values in comparison with the control, untreated strain. The most pronounced inhibition (87.4%) of S. aureus growth was observed after the application of graphene oxide composite with selenium nanoparticles compared to control. Moreover, the application of the composite with silver and silver phosphate nanoparticles showed the decrease of 68.8% and 56.8%, respectively. For all the tested composites, the observed antimicrobial effect was found in the range of 26% to 87.4%. Interestingly, the effects of the composites with selenium nanoparticles significantly differed in Gram-positive (G⁺) and Gram-negative (G⁻) bacteria. The effects of composites on bacterial cultures of S. aureus and MRSA, the representatives of G⁺ bacteria, increased with increasing concentrations. On the other hand, the effects of the same composites on G⁻ bacteria E. coli was observed only in the highest applied concentration.     

Distinguishing Neural Adaptation and Predictive Coding Hypotheses in Auditory Change Detection

The auditory mismatch negativity (MMN) component of event-related potentials (ERPs) has served as a neural index of auditory change detection. MMN is elicited by presentation of infrequent (deviant) sounds randomly interspersed among frequent (standard) sounds. Deviants elicit a larger negative deflection in the ERP waveform compared to the standard. There is considerable debate as to whether the neural mechanism of this change detection response is due to release from neural adaptation (neural adaptation hypothesis) or from a prediction error signal (predictive coding hypothesis). Previous studies have not been able to distinguish between these explanations because paradigms typically confound the two. The current study disambiguated effects of stimulus-specific adaptation from expectation violation using a unique stimulus design that compared expectation violation responses that did and did not involve stimulus change. The expectation violation response without the stimulus change differed in timing, scalp distribution, and attentional modulation from the more typical MMN response. There is insufficient evidence from the current study to suggest that the negative deflection elicited by the expectation violation alone includes the MMN. Thus, we offer a novel hypothesis that the expectation violation response reflects a fundamentally different neural substrate than that attributed to the canonical MMN.     

Comparison of short- with long-term regeneration results after digital nerve reconstruction with musclein-vein conduits

Muscle-in-vein conduits are used alternatively to nerve grafts for bridging nerve defects. The purpose of this study was to examine short- and long-term regeneration results after digital nerve reconstruction with muscle-in-vein conduits. Static and moving two-point discriminations and Semmes-Weinstein Monofilaments were used to evaluate sensory recovery 6–12 months and 14–35 months after repair of digital nerves with muscle-in-vein in 7 cases. Both follow-ups were performed after clinical signs of progressing regeneration disappeared. In 4 of 7 cases, a further recovery of both two-point discriminations and in another case of only the static two-point discrimination of 1–3 mm could be found between the short-term and long-term follow-up examination. Moreover, a late recovery of both two-point discriminations was demonstrated in another case. Four of 7 cases showed a sensory improvement by one Semmes-Weinstein Monofilaments. This pilot study suggests that sensory recovery still takes place even when clinical signs of progressing regeneration disappear.