Expression of Recombinant pET22b-LysK-Cysteine/Histidine-Dependent Amidohydrolase/Peptidase Bacteriophage Therapeutic Protein in Escherichia coli BL21 (DE3)

Production of mannooligosaccharides from orange peel waste with β-mannanase expressed in Trichosporonoides oedocephalis

A large quantity of orange peel waste (OPW) is generated per year, yet effective biorefinery methods are lacking. In this study, Trichosporonoides oedocephalis ATCC 16958 was employed for hydrolyzing OPW to produce soluble sugars. Glycosyl hydrolases from Paenibacillussp.LLZ1 which can hydrolyze cellulose and hemicellulose were mined and characterized, with the highest β-mannanase activity of 39.1 U/mg at pH 6.0 and 50 ℃. The enzyme was overexpressed in T. oedocephalis and the sugar production was enhanced by 16 %. The accumulated sugar contains 57 % value-added mannooligosaccharides by the hydrolysis of mannans. The process was intensified by a pretreatment combining H2O2 submergence and steam explosion to remove potential inhibitors. The mannooligosaccharides yield of 6.5 g/L was achieved in flask conversion and increased to 9.7 g/L in a 5-L fermenter. This study improved the effectiveness of orange peel waste processing, and provided a hydrolysis-based methodology for the utilization of fruit wastes.

Production of Egg Yolk Antibody (IgY) Against Vibrio Cholerae O1: Protective Effect in Mice

BACKGROUND

Cholera is an acute intestinal infection caused by Vibrio cholera (V. cholera). The development of antibodies against specific V. cholerae may have a therapeutic effect. In the present research, we investigated the protective effect of egg yolk Immunoglobulin (IgY), which was produced by immunizing hens with formaldehyde-killed V. cholerae O1 and subsequently the isolated IgY was orally administrated to the V. cholerae O1 infected mice for evaluation of its immunizing capability.

METHODS

In the current study, hens were immunized three times with formaldehyde-killed V. cholerae O1 (1.5×107 CFU/ml) and an equal volume of adjuvant. The IgY was isolated from egg yolk by polyethylene glycol method. The validity and activity of isolated IgY were confirmed with SDS-PAGE and ELISA methods, respectively. Subsequently IgY was orally administered to suckling mice following challenge with V. cholerae O1. ELISA results showed high antibody titer in the serum and egg yolk. Also, SDS-PAGE analysis showed successful purification of IgY and anti-V. cholerae IgY prevented the death of mice infected with V. cholerae O1. The anti-V. cholera IgY was administered at 2, 4, 6 hr intervals after 3 hr of inoculation of mice with V. cholerae O1.

RESULTS

Results showed that the rate of surviving mice (2 mg/ml of IgY) were 60% after 4 hr and 40% after 6 hr and the rate of surviving mice (5 mg/ml of IgY) was 70% after 4 hr and 60% after 6 hr.

CONCLUSION

The findings suggested the egg yolk-driven IgY as a natural antibacterial protein, could be effective in the prevention and treatment of cholera disease.

Chemotherapeutic Strategies for Combating Staphylococcus aureus Infections

Staphylococcus aureus is a prominent human pathogen that causes nosocomial and community acquired infections. The accelerating emergence and prevalence of staphylococcal infections have grotesque health consequences which are mostly due to its anomalous capability to acquire drug resistance and scarcity of novel classes of antibacterials. Many combating therapies are centered on primary targets of S. aureus which are cell envelope, ribosomes and nucleic acids. This review describes various chemotherapeutic strategies for combating S. aureus infections which includes monotherapy, combination drug therapy, phage endolysin therapy, lysostaphins and antibacterial drones. Monotherapy has dwindled in due course of time but combination therapy, endolysin therapy, lysostaphin and antibacterial drones are emerging alternatives which efficiently conquer the shortcomings of monotherapy. Combinations of more than one antibiotic agents or combination of adjuvant with antibiotics provide a synergistic approach to combat infections causing pathogenic strains. Phage endolysin therapy and lysostaphin are also presents as possible alternatives to conventional antibiotic therapies. Antibacterial Drones goes a step further by specifically targeting the virulence genes in bacteria giving them a certain advantage over existing antibacterial strategies. But the challenge remains on the better understanding of these strategies for executing and implementing them in health sector. In this day and age, most of the S. aureus strains are resistant to ample number of antibiotics, so there is an urgent need to overcome such multidrug resistant strains for the welfare of our community.

Effect of intraoperative dexmedetomidine infusion during functional endoscopic sinus surgery: a prospective cohort study

Background

Dexmedetomidine, an α2 agonist, has well-known anesthetic and analgesic-sparing effects. We designed this study to evaluate the effect of intraoperative dexmedetomidine infusion on intra operative blood loss and postoperative pain in functional endoscopic sinus surgery.

Methods

This prospective cohort study included 90 patients planning to undergo endoscopic sinus surgery, who were randomly divided into three groups. 2 to 2.5 mg/kg of propofol was used in all groups to induce anesthesia. One group received dexmedetomidine 0.2 μg/kg per hour infusion whereas the other group received dexmedetomidine 0.5 μg/kg per hour infusion. The control group received normal saline infusion.

Results

The mean age of patients was 41.02 ± 11.93. 33 patients in the dexmedetomidine 0.2 μg/kg/h group, 30 patients in the dexmedetomidine 0.5 μg/kg/h group and 27 patients in the placebo group. The lowest amount of bleeding was related to the dexmedetomidine 0.5 μg/kg/h group. The volume of bleeding between the three groups was significantly different (p = 0.012). The satisfaction of the surgeon in the dexmedetomidine 0.5 μg/kg/h group was more than other groups. There was a significant relationship between the satisfaction of the surgeon and the treatment groups (p < 0.001). The lowest duration of surgery was related to the dexmedetomidine 0.2 μg/kg/h group. The most Trinitroglycerin (TNG) consumption was in the placebo group and the highest dose of labetalol was in the dexmedetomidine 0.5 μg/kg/h group. There was no significant difference in the TNG and labetalol consumption between three groups. The lowest consumption of morphine and pethidine in the dexmedetomidine 0.5 μg/kg/h group.

Conclusions

Infusion of dexmedetomidine 0.5 μg/kg/h decreased blood loss and consumption of morphine and pethidine in patients who underwent endoscopic sinus surgery.

Antimicrobial peptides of the vaginal innate immunity and their role in the fight against sexually transmitted diseases

Some antimicrobial peptides (AMPs) are produced in the vaginal innate immune system and play an important role in protecting this organ against pathogenic agents. Moreover, sexually transmitted diseases have become a major problem in human societies and are rapidly spreading. The emergence of antibiotic-resistant microbes (superbugs) can pose a major threat to human societies and cause rapid spread of these diseases. Finding new antimicrobial compounds to fight superbugs is therefore essential. It has been shown that AMPs have good potential to become new antibiotics. The most important AMPs in the vaginal innate immune system are defensins, secretory leucocyte protease inhibitors, calprotectin, lysozyme, lactoferrin and elafin, which play an important role in host defence against sexually transmitted infections, modulation of immune responses and anticancer activities. Some AMPs, such as LL-37, magainin 2 and nisin, show both spermicidal and antimicrobial effects in the vagina. In this summary, we will discuss vaginal AMPs and continue to address some of the challenges of using peptides to control pathogens that are effective in sexually transmitted diseases.

Evaluation of Cisplatin Efficacy on HepG2 and E. coli Cells under Acidic Conditions

Background: Cisplatin (Cispt) is a common anticancer drug for the treatment of several malignancies, including hepatocarcinoma. However, this drug suffers from instability in aqueous solutions. The study aimed to evaluate cisplatin efficacy on HepG2 and E. coli cells under an acidic condition. Methods: Acidic Cispt was prepared via incubation in acidic condition (pH=2) for a month duration. The chemical structure of the acidic Cispt was evaluated by using Fourier Transform Infrared Spectroscopy (FTIR) method. The cytotoxicity of the standard and acidic Cispt were then determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and minimum inhibitory concentration (MIC) assays on HepG2 and E. coli cells, respectively. Results: After preparing of acidic Cispt, its chemical structure was determined by FTIR method. In addition, cytotoxicity effects of Cispt in the standard and acidic forms were calculated 58 ± 2.9 and 65 ± 3.25 μM, respectively. MIC results also confirmed the results of MTT assay. MIC results for the standard and acidic Cispt were estimated 9.5 ± 0.47 and 9.8 ± 0.49 μM, respectively. Conclusion: Preparing Cispt in acidic condition not only did not degrade the drug, but also kept the potency of the drug approximately equal to parent drug. Regarding the instability issues of Cispt, keeping Cispt in acidic condition could be a promising approach to preserve its efficacy.

The Role of Probiotics in the Treatment of Dysentery: a Randomized Double-Blind Clinical Trial

Diarrhea is considered as an important cause of morbidity and mortality, even though one of the main reasons of death following diarrhea is initiated by dysentery. In recent years, the consumption of probiotics has been proposed for the treatment of infectious diarrhea. Despite most of the studies on probiotics have focused on acute watery diarrhea, few studies in the field of dysentery have found beneficial effects of probiotics. This study is a randomized double-blind clinical trial. The patients were randomly placed into control and case groups. In the intervention group, the patients received probiotics in the form of Kidilact® sachet, which contained high amounts of 7-strain friendly bacteria strains of Lactobacillus casei, Lactobacillus acidophilus, Lactobacillus rhamnosus, Lactobacillus bulgaricus, Bifidobacterium infantis, Bifidobacterium breve, and Streptococcus thermophiles. On the other hand, the patients in the control group received placebo sachets on a daily basis for 5 days. It is notable that the treatment protocol of acute dysentery was done on both groups. The results of this study showed significant differences in the duration of blood in diarrhea between probiotic consumers (2.62 days) and the control group (3.16 days) (P value = 0.05). Additionally, significant differences in the average length of hospitalization in probiotic consumers (3.16 days) and control (3.66 days), (P value = 0.02) could be claimed that the consumption of probiotics is effective in reducing the duration of dysentery and diarrhea. The results of this study suggest that the use of probiotics can be effective in reducing the duration of blood in diarrhea. This study was also recorded in the Iran center of clinical trials registration database (IRCT2014060617985N1).

Purification of Antibacterial CHAPK Protein Using a Self-Cleaving Fusion Tag and Its Activity Against Methicillin-Resistant Staphylococcus aureus

Therapeutic LysK-CHAP is a potent anti-staphylococcal protein that could be utilized as an antibiotic substitute. Intein-mediated protein purification is a reasonable and cost-effective method that is most recently used for recombinant therapeutic protein production. Intein (INT) is the internal parts of the protein that can be separated from the immature protein during protein splicing process. This sequence requires no specific enzyme or cofactor for separation. INT sequence and their characteristic of self-cleavage by thiol induction, temperature, and pH changes are used for protein purification. The current study presents the expression of CHAP_K262 domain of LysK gene that is fused with INT/chitin-binding sequence while evaluating its purification procedure and antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA). The coding gene sequence of LysK-CHAP (CHAP_K262) in pET22-b was amplified with polymerase chain reaction (PCR); the digested product was then cloned into the pTXB1 vector. Electrophoresis confirmed the cloning accuracy of the gene. The pTXB1-CHAP_K262 plasmid was transformed to the Escherichia coli ER₂₅₆₆ (E. coli ER₂₅₆₆) expression strain and analyzed for expression of the recombinant protein by SDS-PAGE and Western blotting methods. Finally, CHAP_K262 was purified by chitin affinity column using INT tag technology and confirmed by SDS-PAGE. Lytic activity of the purified protein was investigated by disk diffusion method. Cloning of CHAP_K262 into the pTXB1 vector, which comprised INT/chitin-binding sequence, was successfully achieved. The SDS-PAGE data also revealed successful expression of the CHAP_K262-INT fusion protein and Western blotting method validated the accuracy of the protein. Moreover, purification of CHAP_K262 protein was induced by dithiothreitol (DTT) and confirmed by SDS-PAGE. Finally, inhibition zone in MRAS culture medium confirmed antibacterial activity of the protein. Application of intein-mediated antibacterial protein is an appropriate and streamlined method for one-step purification of CHAP_K262 as a therapeutic and antibacterial protein. Self-cleaving tags like intein are cost-effective and could be used as a proper purification method for industrial purposes.

Dengue viruses and promising envelope protein domain III-based vaccines

Dengue viruses are emerging mosquito-borne pathogens belonging to Flaviviridae family which are transmitted to humans via the bites of infected mosquitoes Aedes aegypti and Aedes albopictus. Because of the wide distribution of these mosquito vectors, more than 2.5 billion people are approximately at risk of dengue infection. Dengue viruses cause dengue fever and severe life-threatening illnesses as well as dengue hemorrhagic fever and dengue shock syndrome. All four serotypes of dengue virus can cause dengue diseases, but the manifestations are nearly different depending on type of the virus in consequent infections. Infection by any serotype creates life-long immunity against the corresponding serotype and temporary immunity to the others. This transient immunity declines after a while (6 months to 2 years) and is not protective against other serotypes, even may enhance the severity of a secondary heterotypic infection with a different serotype through a phenomenon known as antibody-depended enhancement (ADE). Although, it can be one of the possible explanations for more severe dengue diseases in individuals infected with a different serotype after primary infection. The envelope protein (E protein) of dengue virus is responsible for a wide range of biological activities, including binding to host cell receptors and fusion to and entry into host cells. The E protein, and especially its domain III (EDIII), stimulates host immunity responses by inducing protective and neutralizing antibodies. Therefore, the dengue E protein is an important antigen for vaccine development and diagnostic purposes. Here, we have provided a comprehensive review of dengue disease, vaccine design challenges, and various approaches in dengue vaccine development with emphasizing on newly developed envelope domain III-based dengue vaccine candidates.

Effect of melatonin in reducing second-generation antipsychotic metabolic effects: A double blind controlled clinical trial

INTRODUCTION

The use of second-generation atypical antipsychotics has an increasing role in the development of metabolic syndrome. However, these medications due to metabolic disorders can lead to an increased risk of cardiovascular disease and subsequently mortality as well as reduced adherence to treatment. The main objective of current study was to determine the ability of melatonin to reduce the metabolic effects of second-generation antipsychotics.

METHODS

This double blind controlled clinical trial was conducted on 100 patients aged 18-64 years old were treated with the second-generation antipsychotics for the first time. The patients were divided randomly into two groups of 50. The case group received slow-release melatonin at a dose of 3mg and the control group was given oral placebo at 8 p.m.

RESULTS

The findings in melatonin group indicated significantly increase of HDL and decreased fasting blood sugar and systolic blood pressure, as well as had statistically significant increase in waist circumference, weight and BMI compared with placebo group.

CONCLUSION

According to the findings, it can be claimed that the addition of melatonin to atypical antipsychotics has led to a reduction in some of the metabolic effects of these drugs. In this study, HDL level was increased, and the mean systolic blood pressure and FBS were decreased in the melatonin group. Considering that these factors are contributing to cardiovascular disease as a leading cause of mortality in psychiatric patients, so the use of melatonin can reduce some of the medical effects of long-term treatment of atypical antipsychotics.

Recombinant Endolysins as Potential Therapeutics against Antibiotic-Resistant Staphylococcus aureus: Current Status of Research and Novel Delivery Strategies

Staphylococcus aureus is one of the most common pathogens of humans and animals, where it frequently colonizes skin and mucosal membranes. It is of major clinical importance as a nosocomial pathogen and causative agent of a wide array of diseases. Multidrug-resistant strains have become increasingly prevalent and represent a leading cause of morbidity and mortality. For this reason, novel strategies to combat multidrug-resistant pathogens are urgently needed. Bacteriophage-derived enzymes, so-called endolysins, and other peptidoglycan hydrolases with the ability to disrupt cell walls represent possible alternatives to conventional antibiotics. These lytic enzymes confer a high degree of host specificity and could potentially replace or be utilized in combination with antibiotics, with the aim to specifically treat infections caused by Gram-positive drug-resistant bacterial pathogens such as methicillin-resistant S. aureus. LysK is one of the best-characterized endolysins with activity against multiple staphylococcal species. Various approaches to further enhance the antibacterial efficacy and applicability of endolysins have been demonstrated. These approaches include the construction of recombinant endolysin derivatives and the development of novel delivery strategies for various applications, such as the production of endolysins in lactic acid bacteria and their conjugation to nanoparticles. These novel strategies are a major focus of this review.

A Novel Chimeric Endolysin with Antibacterial Activity against Methicillin-Resistant Staphylococcus aureus

Cysteine/histidine-dependent amidohydrolase/peptidase (CHAP) and amidase are known as catalytic domains of the bacteriophage-derived endolysin LysK and were previously reported to show lytic activity against methicillin-resistant Staphylococcus aureus (MRSA). In the current study, the in silico design and analysis of chimeric CHAP-amidase model was applied to enhance the stability and solubility of protein, which was achieved through improving the properties of primary, secondary and tertiary structures. The coding gene sequence of the chimeric CHAP-amidase was synthesized and subcloned into the pET-22(+) expression vector, and the recombinant protein was expressed in E. coli BL21 (DE3) strain. Subsequent affinity-based purification yielded ~12 mg soluble protein per liter of E. coli culture. Statistical analysis indicated that concentrations of ≥1 μg/mL of the purified protein have significant antibacterial activity against S. aureus MRSA₂₅₂ cells. The engineered chimeric CHAP-amidase exhibited 3.2 log reduction of MRSA₂₅₂ cell counts at the concentration of 10 μg/mL. A synergistic interaction between CHAP-amidase and vancomycin was detected by using checkerboard assay and calculating the fractional inhibitory concentration (FIC) index. This synergistic effect was shown by 8-fold reduction in the minimum inhibitory concentration of vancomycin. The chimeric CHAP-amidase displayed strong antibacterial activity against S. aureus, S. epidermidis, and enterococcus. However, it did not indicate any significant antibacterial activity against E. coli and Lactococcus lactis. Taken together, these findings suggest that our chimeric CHAP-amidase might represent potential to be used for the development of efficient antibacterial therapies targeting MRSA and certain Gram-positive bacteria.

Comparing Apoptosis and Necrosis Effects of Arctium Lappa Root Extract and Doxorubicin on MCF7 and MDA-MB-231 Cell Lines

Objective: Breast cancer is a heterogeneous disease and very common malignancy in women worldwide. The efficacy of chemotherapy as an important part of breast cancer treatment is limited due to its side effects. While pharmaceutical companies are looking for better chemicals, research on traditional medicines that generally have fewer side effects is quite interesting. In this study, apoptosis and necrosis effect of Arctium lappa and doxorubicin was compared in MCF7, and MDA-MB-231 cell lines. Materials and Methods: MCF7 and MDA-MB-231 cells were cultured in RPMI 1640 containing 10% FBS and 100 U/ml penicillin/streptomycin. MTT assay and an annexin V/propidium iodide (AV/PI) kit were used respectively to compare the survival rate and apoptotic effects of different concentrations of doxorubicin and Arctium lappa root extract on MDA-MB-231 and MCF7 cells. Results: Arctium lappa root extract was able to reduce cell viability of the two cell lines in a dose and time dependent manner similar to doxorubicin. Flow cytometry results showed that similar to doxorubicin, Arctium Lappa root extract had a dose and time dependent apoptosis effect on both cell lines. 10μg/mL of Arctium lappa root extract and 5 μM of doxorubicin showed the highest anti-proliferative and apoptosis effect in MCF7 and MDA231 cells. Conclusion: The MCF7 (ER/PR-) and MDA-MB-231 (ER/PR+) cell lines represent two major breast cancer subtypes. The similar anti-proliferative and apoptotic effects of Arctium lappa root extract and doxorubicin (which is a conventional chemotherapy drug) on two different breast cancer cell lines strongly suggests its anticancer effects and further studies.

Correlation between Epstein-Barr Virus Infection and Disease Activity of Systemic Lupus Erythematosus: a Cross-Sectional Study

Background:

Systemic lupus erythematosus (SLE) is an autoimmune disease for whose pathogenesis viral infections are important. The Epstein-Barr virus (EBV) is the main infectious etiological agent. This study aimed to quantitative evaluation of EBV in SLE patients.

Materials and Methods:

In this cross-sectional study, 40 patients with SLE diagnosed based on American College of Rheumatology criteria were selected using purposive sampling. All were included in the study after obtaining informed consent for participation. Whole blood samples were taken and buffy coat preparations were isolated to determine viral load using the real-time polymerase chain reaction method and assessment with the SLE disease activity index (SLE-DAI).

Results:

From a total of 40 patients, 37 cases (92.5%) were women. The EBV test was positive in 67.5% and mean viral load was 5396 ± 1891.9 copy/ml. Twenty of forty patients had active and 50% inactive disease, mean EBV viral loads being 6798 and 28.25 copy/ml, respectively (P-value = 0.003). In terms of the severity of disease activity, 17.5 % of female patients had mild to moderate activity, whilst 32.5% of them had severe activity, with respective viral loads of 5,803.3 and 29.73 copy/ml (P-value = 0.003).

Conclusion:

The Epstein-Barr viral load in SLE patients with active disease was found to be markedly higher than in inactive cases. Thus, EBV may have an important role in the pathogenesis and activity of SLE.

Diagnostic Value of Neuron-Specific Enolase (NSE) and Cancer Antigen 15-3 (CA 15-3) in the Diagnosis of Pleural Effusions

Introduction: Pleural effusion diagnosis plays an important role in determining treatment strategies. The aim of this study was to determine the diagnostic capacity of tumor markers CA 15-3 and NSE solely or in combination in differentiating the nature of pleural fluid. Methods and Materials: In this cross-sectional study we evaluated 93 patients with pleural effusions (44 malignant and 49 benign). NSE and CA 15-3 serum and pleural levels were measured simultaneously using immunoenzyme assay kits. Diagnosis was established on the basis of cytological study. Results: Sensitivity and specificity of CA 15-3 serum and pleural level measurement were 70.4%, 49.0%, and 79.5% and 49.0%, respectively. Serum NSE levels had 75.0% sensitivity and 69.4% specificity while the respective pleural figures were 75.0% and 73.5%. The combination of NSE and CA 15-3 serum and pleural levels had the highest sensitivity (93.2%), although combined serum levels had the lowest sensitivity (47.7%). With an accuracy of 74.2%, pleural levels of NSE had the highest diagnostic potential. Conclusion: Measuring NSE and CA 15-3 tumor markers is a suitable approach to distinguish the nature of pleural effusions, with NSE pleural levels demonstrating the highest diagnostic accuracy.