Discovery of a novel antibacterial protein CB6-C to target methicillin-resistant Staphylococcus aureus

Given a serious threat of multidrug-resistant bacterial pathogens to global healthcare, there is an urgent need to find effective antibacterial compounds to treat drug-resistant bacterial infections. In our previous studies, Bacillus velezensis CB6 with broad-spectrum antibacterial activity was obtained from the soil of Changbaishan, China. In this study, with methicillin-resistant Staphylococcus aureus as an indicator bacterium, an antibacterial protein was purified by ammonium sulfate precipitation, Sephadex G-75 column, QAE-Sephadex A 25 column and RP-HPLC, which demonstrated a molecular weight of 31.405 kDa by SDS-PAGE. LC–MS/MS analysis indicated that the compound was an antibacterial protein CB6-C, which had 88.5% identity with chitosanase (Csn) produced by Bacillus subtilis 168. An antibacterial protein CB6-C showed an effective antimicrobial activity against gram-positive bacteria (in particular, the MIC for MRSA was 16 μg/mL), low toxicity, thermostability, stability in different organic reagents and pH values, and an additive effect with conventionally used antibiotics. Mechanistic studies showed that an antibacterial protein CB6-C exerted anti-MRSA activity through destruction of lipoteichoic acid (LTA) on the cell wall. In addition, an antibacterial protein CB6-C was efficient in preventing MRSA infections in in vivo models. In conclusion, this protein CB6-C is a newly discovered antibacterial protein and has the potential to become an effective antibacterial agent due to its high therapeutic index, safety, nontoxicity and great stability.

Balanoposthitis: issues of classification, diagnosis and approaches to therapy

Objective. To present a variant of the modern classification of the processes occurring with lesions of the genitals, to draw specialists’ attention to the peculiarities and variety of causes leading to inflammation of the glans and foreskin, as well as to discuss topical issues of external therapy of balanopostitis.Material and methods. Data from modern studies and clinical guidelines were used in the preparation of the publication.Results. The variety of variants of lesions of the glans and foreskin can be due to a number of reasons and can be either an independent local process or a fragment of dermatosis, where it is possible to be affected in the form of balanoposthitis. Also, when examining and selecting therapy options, it is important to consider the possible role of microorganisms, whose spectrum as a cause of balanoposthitis varies from aerobic and anaerobic, to viral and fungal microflora. Treatment approaches are determined by the etiological factors.Conclusions. Balanoposthitis is a heterogeneous group of nosologies. The choice of treatment is based on the identified cause or empirically when possible. External therapy and hygiene constitute an essential part of treatment. When choosing drugs for topical glucocorticosteroids, preferenceshould be given to drugs with a high therapeutic index and low atrophogenic potential. Dysplastic processes of the penis are associated with human papillomavirus infection, the treatment of which can be both conservative and destructive.

Ameliorative Role of Nutraceutical Quercetin and its Derivatives Against Cognitive Impairment Process Induced by Lead Exposure in Drosophila melanogaster(Fruit Fly)

Cumulative lifetime lead (Pb) exposure has been associated with accelerated declines in cognition through the free radical generation and epigenetic effects. Several pieces of literature have identified a correlation between exposure to lead and neurodegenerative disorders. Harwich strain Drosophila melanogaster was exposed to lead acetate for two weeks, and changes in pulse transmission by acetylcholinesterase and systemic redox were evaluated. Besides, molecular docking studies of acetylcholinesterase against Quercetin and its most common derivatives contained in food have been performed. Pharmacokinetic studies on Quercetin and its derivatives have also been performed in silico toxicity. The data obtained showed alterations in antioxidant enzymes and molecules such as catalase, glutathione-S-transferase, and glutathione. Upregulation of acetylcholinesterase activity was observed after treatment with Quercetin. In molecular docking tests, Quercetin and its derivatives were found to bind to acetylcholinesterase's active and peripheral pockets. Pharmacokinetic studies demonstrate moderate solubility, high therapeutic index, excellent absorption potential, hepatoprotective and non-mutagenic properties. With other antioxidant molecules, Quercetin may also play a crucial role in avoiding the development of Alzheimer's and associated antioxidant disorders.

Discovery of a Novel Antibacterial Protein CB6-C to Target Methicillin-Resistant Staphylococcus Aureus

Given the serious threat of multidrug-resistant bacterial pathogens to global healthcare, there is an urgent need to find effective antibacterial compounds to treat drug-resistant bacterial infections. In our previous studies, Bacillus velezensis CB6 with broad-spectrum antibacterial activity was obtained from the soil of Changbaishan, China. In this study, with MRSA as an indicator bacterium, an antibacterial protein was purified by ammonium sulfate precipitation, a Sephadex G-75 column, a QAE-Sephadex A 25 column and RP-HPLC, which demonstrated a molecular weight of 31405.48 Da by SDS-PAGE. LC-MS/MS analysis indicated that the compound was an antibacterial protein CB6-C, which had 88.5% homology with chitosanase Csn produced by Bacillus subtilis 168. An antibacterial protein CB6-C showed an effective antimicrobial activity against gram-positive bacteria (in particular, the MIC for MRSA was 16 μg/mL), low toxicity, thermostability, stability in different organic reagents and pH values, and an additive effect with conventionally used antibiotics. Mechanistic studies showed that an antibacterial protein CB6-C exerted anti-MRSA activity through destruction of lipoteichoic acid (LTA) on the cell wall. In addition, an antibacterial protein CB6-C was efficient in preventing MRSA infections in In Vivo models. In conclusion, this protein CB6-C is a newly discovered antibacterial protein and has the potential to become an effective antibacterial agent due to its high therapeutic index, safety, nontoxicity and great stability.

Serenoa Repens (Saw Palmetto) for Lower Urinary Tract Symptoms (LUTS): The Evidence for Efficacy and Safety of Lipidosterolic Extracts. Part II

Part I of this 3-part series provided the groundwork for understanding the role of a standardized lipidosterolic extract of Serenoa repens (LSESr) in the treatment of LUTS. It documented that a treatment having a high therapeutic index (i.e., a ratio of benefit to adverse reactions) is a critical need in the demographic context of a rapidly growing elder population. Part I described the clinical symptomatology of LUTS and how it is quantified. A critique of the reports from four authoritative bodies: the European Scientific Cooperative on Phytotherapy (ESCOP), Cochrane 2012, the European Medicines Agency (EMA), and the AUA (American Urological Association) was presented. The foundation above then fine-tuned our search to require (a) consistent evaluability criteria, (b) the quantification of clinical findings, (c) the need to focus on studies employing a standardized LSESr product meeting the fatty acid profile set forth by the European Medicines Agency (EMA) and the US Pharmacopeia and (d) a global assessment of scientific investigations published in all languages and not limited to only English. With the above four constraints, “new” findings about LSESr vs. LUTS are presented. How did the search strategy and selection criteria lead to new understandings about the role of LSESr vs. LUTS? How safe is LSESr in contrast to its counterpart prescription drugs? Of the proposed major mechanisms of action of LSESr (e.g., 5-alpha reductase inhibition and anti-inflammatory activity), what are the key points? After initiating treatment with LSESr, when is clinical improvement seen? How durable is LSESr in ameliorating LUTS? Can LSESr prevent the progression of BPH?

Site-Specific Antibody Conjugation to Engineered Double Cysteine Residues

Site-specific antibody conjugations generate homogeneous antibody-drug conjugates with high therapeutic index. However, there are limited examples for producing the site-specific conjugates with a drug-to-antibody ratio (DAR) greater than two, especially using engineered cysteines. Based on available Fc structures, we designed and introduced free cysteine residues into various antibody CH2 and CH3 regions to explore and expand this technology. The mutants were generated using site-directed mutagenesis with good yield and properties. Conjugation efficiency and selectivity were screened using PEGylation. The top single cysteine mutants were then selected and combined as double cysteine mutants for expression and further investigation. Thirty-six out of thirty-eight double cysteine mutants display comparable expression with low aggregation similar to the wild-type antibody. PEGylation screening identified seventeen double cysteine mutants with good conjugatability and high selectivity. PEGylation was demonstrated to be a valuable and efficient approach for quickly screening mutants for high selectivity as well as conjugation efficiency. Our work demonstrated the feasibility of generating antibody conjugates with a DAR greater than 3.4 and high site-selectivity using THIOMABTM method. The top single or double cysteine mutants identified can potentially be applied to site-specific antibody conjugation of cytotoxin or other therapeutic agents as a next generation conjugation strategy.

Serenoa repens (Saw Palmetto) for Lower Urinary Tract Symptoms (LUTS): The Evidence for Efficacy and Safety of Lipidosterolic Extracts. Part II

Part I of this 3-part series provided the groundwork for understanding the role of a standardized lipidosterolic extract of Serenoa repens (LSESr) in the treatment of LUTS. It documented that a treatment having a high therapeutic index (i.e., a ratio of benefit to adverse reactions) is a critical need in the demographic context of a rapidly growing elder population. Part I described the clinical symptomatology of LUTS and how it is quantified. A critique of the reports from four authoritative bodies: the European Scientific Cooperative on Phytotherapy (ESCOP), Cochrane 2012, the European Medicines Agency (EMA), and the AUA (American Urological Association) was presented. The foundation above then fine-tuned our search to require (a) consistent evaluability criteria, (b) the quantification of clinical findings, (c) the need to focus on studies employing a standardized LSESr product meeting the fatty acid profile set forth by the European Medicines Agency (EMA) and the US Pharmacopeia and (d) a global assessment of scientific investigations published in all languages and not limited to only English. Part II details the following “new” findings when LSESr vs. LUTS is examined with the above constraints.

Clinical evaluation of labor: an evidence- and experience-based approach

During labor mother and fetus are evaluated at intervals to assess their well-being and determine how the labor is progressing. These assessments require skillful physical diagnosis and the ability to translate the acquired information into meaningful prognostic decision-making. We describe a coordinated approach to the assessment of labor. Graphing of serial measurements of cervical dilatation and fetal station creates “labor curves,” which provide diagnostic and prognostic information. Based on these curves we recognize nine discrete labor abnormalities. Many may be related to insufficient or disordered contractile mechanisms. Several factors are strongly associated with development of labor disorders, including cephalopelvic disproportion, excess analgesia, fetal malpositions, intrauterine infection, and maternal obesity. Clinical cephalopelvimetry involves assessing pelvic traits and predicting their effects on labor. These observations must be integrated with information derived from the labor curves. Exogenous oxytocin is widely used. It has a high therapeutic index, but is easily misused. Oxytocin treatment should be restricted to situations in which its potential benefits clearly outweigh its risks. This requires there be a documented labor dysfunction or a legitimate medical reason to shorten the labor. Normal labor and delivery pose little risk to a healthy fetus; but dysfunctional labors, especially if stimulated excessively by oxytocin or terminated by complex operative vaginal delivery, have the potential for considerable harm. Conscientiously implemented, the approach to the evaluation of labor outlined in this review will result in a reasonable cesarean rate and minimize risks that may accrue from the labor and delivery process.

Nanoparticle-based Drug Delivery Systems for Targeted Epigenetics Cancer Therapy

This review summarizes the epigenetic mechanisms of deoxyribonucleic acid (DNA) methylation, histone modifications in cancer and the epigenetic modifications in cancer therapy. Due to their undesired side effects, the use of epigenetic drugs as chemo-drugs in cancer therapies is limited. The drug delivery system opens a door for minimizing these side effects and achieving greater therapeutic benefits. The limitations of current epigenetic therapies in clinical cancer treatment and the advantages of using drug delivery systems for epigenetic agents are also discussed. Combining drug delivery systems with epigenetic therapy is a promising approach to reaching a high therapeutic index and minimizing the side effects.