Solid lipid nanoparticles and their application in the treatment of bacterial infectious diseases

Nano pharmacology is considered an effective, safe, and applicable approach for drug delivery applications. Solid lipid nanoparticle (SLNs) colloids contain biocompatible lipids which are capable of encapsulating and maintaining hydrophilic or hydrophobic drugs in the solid matrix followed by releasing the drug in a sustained manner in the target site. SLNs have more promising potential than other drug delivery systems for various purposes. Nowadays, the SLNs are used as a carrier for antibiotics, chemotherapeutic drugs, nucleic acids, herbal compounds, etc. The SLNs have been widely applied in biomedicine because of their non-toxicity, biocompatibility, and simple production procedures. In this review, the complications related to the optimization, preparation process, routes of transplantation, uptake and delivery system, and release of the loaded drug along with the advantages of SLNs as therapeutic agents were discussed.

Characterization of recombinant phytase of Klebsiella sp. and the influence of novel 3-phytase on mineral solubility in broiler diets under an in vitro digestion assay

Phytate (inositol hexaphosphate) is the major storage form of phosphorus (P) in nature, and phytases catalyze the hydrolysis of P from phytate and the formation of inositol phosphate isomers. In this study, a bacterium that produces phytase was isolated in a phytase screening medium. The bacterium was identified as Klebsiella sp. using phenotypic and molecular techniques. The PhyK phytase gene was successfully amplified from the genome, inserted into the pET-21a (+) vector, and expressed as a recombinant protein in E. Coli BL21. The efficiency of a laboratory phytase (Lab-Ph, PhyK phytase) was determined and compared with a commercial phytase (Com-Ph, Quantum Blue 40P phytase, AB Vista) under an in vitro digestion assay. The native signal peptide effectively facilitated the translocation of the protein to the periplasmic space of E. Coli BL21, resulting in the proper folding of the protein and the manifestation of desirable enzyme activity. The Lab-Ph displayed the temperature and pH optima at 50 °C and 5 respectively. In addition, the Lab-Ph was inactivated at 80 °C. Under an in vitro digestion assay condition, Lab-Ph improved the P solubility coefficient in broiler diets. In comparison, the Com-Ph significantly increased the P solubility coefficient even when compared with the Lab-Ph. In summary, this study has shown that Lab-Ph possesses the necessary biochemical properties to be used in various industrial applications. However, Lab-Ph is extremely sensitive to heat treatment. The Lab-Ph and Com-Ph under an in vitro digestion assay improved the solubility coefficient of P in the broiler diet.

Approaches to determine the efficiency of novel 3-phytase from Klebsiella pneumoniae and commercial phytase in broilers from 1 to 14 d of age

This study aimed to evaluate the effects of a laboratory 3-phytase (the expression of the phyK gene, Lab-Phy) and a commercial 6-phytase (Quantum Blue 40 P, Com-Phy) alone and in combination (corn-soy-based diets) in broilers. A total of 400, day-old Ross 308 male broilers were randomly assigned to 5 treatments with 10 replicate cages (8 chicks/cage) for a 14-day trial. Experimental treatments included the positive control (0.95% Ca and 0.48% nonphytate phosphorus (nPP), PC), negative control (0.90% Ca and 0.22% nPP, NC), and NC which was supplemented with Lab-Phy 250 FTU/kg and Com-Phy 250 FTU/kg alone or in combination of Lab-Phy 125 FTU/kg and Com-Phy 125 FTU/kg. The inclusion of Lab-Phy in the NC diet significantly improved the P and Ca content in the tibia compared to the NC group. Moreover, the inclusion of Com-Phy alone and in combination with Lab-Phy in the NC diet significantly increased the P and Ca content in the tibia compared to the Lab-Phy. The mRNA expression of NaPi-IIb was upregulated in the duodenum by the reduction of nPP and downregulated by the inclusion of any phytase, whereas other nutrient transporters were not influenced by the reduction of nPP or the addition of phytase in the small intestine mucosa. Broilers receiving the NC diet obtained the lowest body weight (BW) and body weight gain (BWG) at 8 to 14 and 1 to 14 d of age. The NC group showed the lowest villi height and surface area, Newcastle disease (ND) antibody titer, and digestibility of nutrients compared to the PC group at 14 d of age. Supplementing the NC diet with the Lab-Phy and Com-Phy individually, or in combination tended to improve BW, BWG, tibia characteristics, villi characteristics, ND, and retained CP and P, and apparent ileal digestibility of CP, P, methionine, and threonine. The present research indicated that the studied traits by the combination of phytases were slightly better than the average of the 2 individually, suggesting there might be some value in combining the laboratory and commercial phytases.

Prognostic biomarkers and molecular pathways mediating Helicobacter pylori–induced gastric cancer: a network-biology approach

Cancer of the stomach is the second most frequent cancer-related death worldwide. The survival rate of patients with gastric cancer (GC) remains fragile. There is a requirement to discover biomarkers for prognosis approaches. Helicobacter pylori in the stomach is closely associated with the progression of GC. We identified the genes associated with poor/favorable prognosis in H. pylori–induced GC. Multivariate statistical analysis was applied on the Gene Expression Omnibus (GEO) dataset GSE54397 to identify differentially expressed miRNAs (DEMs) in gastric tissues with H. pylori–induced cancer compared with the H. pylori–positive with non-cancerous tissue. A protein interaction map (PIM) was built and subjected to DEMs targets. The enriched pathways and biological processes within the PIM were identified based on substantial clusters. Thereafter, the most critical genes in the PIM were illustrated, and their prognostic impact in GC was investigated. Considering p-value less than 0.01 and |Log2 fold change| as >1, five microRNAs demonstrated significant changes among the two groups. Gene functional analysis revealed that the ubiquitination system, neddylation pathway, and ciliary process are primarily involved in H. pylori–induced GC. Survival analysis illustrated that the overexpression of DOCK4, GNAS, CTGF, TGF-b1, ESR1, SELE, TIMP3, SMARCE1, and TXNIP was associated with poor prognosis, while increased MRPS5 expression was related to a favorable prognosis in GC patients. DOCK4, GNAS, CTGF, TGF-b1, ESR1, SELE, TIMP3, SMARCE1, TXNIP, and MRPS5 may be considered prognostic biomarkers for H. pylori–induced GC. However, experimental validation is necessary in the future.

The Effect of Helicobacter pylori Infection on Overweight: A Systematic Review and Meta-Analysis

Background

The association between Helicobacter pylori infection and overweight, as one of the most common health issues, remains controversial. In this study, we systematically reviewed the effect of H. pylori infection and overweight to get a reliable answer.

Methods

We used the Preferred Reporting Items for the Systematic Review and Meta-Analysis statement. We searched the association between H. pylori and overweight infection in international databases including Medline, Web of knowledge and Scopus, without any limitations of language, publication type, and publication status in search step of this systematic review from 2000 to 2020. We surveyed the title, abstract and full text of each research studies, and we used Newcastle-Ottawa quality for assessing the quality of each paper. A random effects model was used to calculate the pooled odd ratio with 95% confidence intervals.

Results

Fifteen papers were eligible for this review. The selected studies reported different Odd Ratio between overweight and H. pylori infection but Odds Ratio (95% confidence interval) in our systematic and meta-analysis study was estimated at 1.42 (95% CI; 1.12, 1.81) and it was statistically significant (P: 0.003).

Conclusion

H. pylori infection is significantly associated with overweight, therefore, the eradication of H. pylori infection is suggested because this infectious might be resulted in overweight.

Antibacterial effects of natural compounds on biofilm formation of Streptococcus mutans

Streptococcus mutans is the main cariogenic pathogen in the oral cavity, considered to contribute toward oral diseases. S. mutans is predominantly entrapped in plaque biofilms.

OBJECTIVES

In this study, we surveyed the antibacterial activity of natural compounds in terms of the biofilm production of S. mutans.

MATERIAL AND METHODS

We extracted the studies related to natural compounds affected on S. mutans biofilm from different databases.

RESULTS

Disruption of S. mutans viability in biofilms by a potent new pharmacological factor could inhibit and remove cavities. Various antibacterial agents are needed to destroy biofilms that remove both pathogens and commensal bacteria, and also exert inhibitory effects on many bacterial species.

CONCLUSIONS

An effective therapeutic agent for dental caries has to be capable of removing pathogens and their biofilms. Specific virulence attributes of S. mutans exist; hence, natural compounds that have excellent properties to combat such pathogens need to be selected.

Evaluation of L-arginine supplement on the growth rate, biofilm formation, and antibiotic susceptibility in Streptococcus mutans

Introduction

Bacteria associated with dental caries have a high ability to produce organic acids from dietary carbohydrates during growth and metabolism under acidic conditions. In contrast, many symbiotic bacteria produce ammonia through the arginine deiminase (ADS) system, which modulates the pH of the oral cavity. l-Arginine metabolism by ADS is a significant inhibitor in the progression of tooth decay. This study aimed to investigate the effect of l-arginine on growth, biofilm formation, and antibiotic susceptibility in Streptococcus mutans.

Methods

In this study, the effect of l-arginine in different concentrations on the growth rate, antibiotic susceptibility, and inhibition of biofilm formation in S. mutans was investigated.

Results

The bacterial exponential growth rate was enhanced by 100 μM l-arginine (P > 0.05). The growth inhibition zone diameter of CAZ, CTR, AMP, and AMC-Clav antibiotics was reduced after 24 h of exposure in the presence of various concentrations of l-arginine specifically at 100 μM. l-Arginine also enhanced biofilm development at 5 and 10 μM concentrations, but reduced it at 50 and 100 μM concentrations.

Conclusion

According to the results of the present study, optimization of l-arginine concentration and its use as an adjunctive therapy or in combination with mouthwash or varnish is recommended to prevent oral caries.

The effects of combination therapy by solid lipid nanoparticle and dental stem cells on different degenerative diseases

Stem cells have multiple therapeutic applications, as well as solid lipid nanoparticles. Solid lipid nanoparticle has appeared as a field of nano lipid technology with various potential applications in drug delivery, clinical medicine and research. Besides, the stem cells have a high proliferation rate and could differentiate into a variety of tissues. Stem cells derived from human dental pulp tissue differ from other sources of mesenchymal stem cells due to their embryonic neural crest source and neurotrophic potential. These consist of both dental pulp stem cells from dental pulp tissues of human permanent teeth and stem cells from human exfoliated deciduous teeth. With the emergence of stem cell banks, stem cells are considering for tissue engineering with respect to therapies attitude and regenerative medicine. The present study aimed to evaluate the advantages and disadvantages of the solid lipid nanoparticle and stem cells combination therapy in different therapeutic applications. The solid lipid nanoparticles have anticancer activity against tumors, induce neural differentiation in pluripotent stem cells, and regulate the mesenchymal stem cells. They also have immunomodulatory effects on human mesenchymal stem cells, the gene transfection efficiency, osteogenic differentiation and bone regeneration. But, the crucial health hazards related to stem cell transplantation such as immune rejection reactions and the interaction with other tissues and the effect of solid lipid nanoparticles must not be neglected. Overall, more experiments need to approve the synergism and antagonism effects of the stem cells and solid lipid nanoparticle combination therapy on different degenerative diseases.

The therapeutic effects of stem cells from human exfoliated deciduous teeth on clinical diseases: a narrative review study

INTRODUCTION

Stem cells isolated from human dental pulp tissue are different from other sources of Mesenchymal stem cells because of their embryonic neural crest sources and neuro-trophic potential. These stem cells consist of dental pulp stem cells from human permanent teeth and stem cells from human exfoliated deciduous teeth.

AIM

In this study, we survey the advantages and disadvantages of these stem cells with therapies attitude.

MAIN TEXT

Stem cells from human exfoliated deciduous teeth with a high proliferation rate could distinguish into a wide types of cells. After stem cell banking appearance, stem cells from human exfoliated deciduous teeth can preserve and use for treatment, especially in regenerative medicine. But the crucial health hazards related to stem cell transplantation, such as immune rejection reactions and the interaction with other tissues, should not be neglected.

CONCLUSION

Further experiments are required to approve the impact of these stem cells on different human disorders.

Characterization of Staphylococcus aureus isolates from pastry samples by rep-PCR and phage typing

Background and Objectives:

Staphylococcus aureus is one of the most common causes of food poisoning. This study aimed to identify S. aureus isolated from pastries, the virulence factors, antimicrobial resistance patterns, biofilm formation, and then classification based on SCCmec types, phage types, and also Rep types.

Materials and Methods:

In this study, 370 creamy and dried pastry samples have been randomly collected from different confectioneries in Hamadan city. The S. aureus isolates were identified by conventional microbiological methods and nuc gene amplification. The virulence factors and prophage genes were detected. After that, the biofilm production and antibiotic susceptibility assay of S. aureus isolates were examined. Finally, the isolates were classified by rep-PCR typing.

Results:

Among 370 samples, 97 creamy (34.64%) and 3 dried (3.33%) pastry samples were contaminated with S. aureus. Antibiotic sensitivity results showed the highest resistance to penicillin (90%) but none of them were MRSA. According to biofilm formation assay, 14 strains (45%) were strongly adhesive. The dominant phage among isolates was SGF, especially SGFa subgroup. About half of the isolates carried SCCmec Types I and III. Analysis of the genetic linkage between isolates by rep-PCR showed ≥80% genetic similarity and also different rep-types of S. aureus isolates.

Conclusion:

The presence of different prophage encoded virulence factors and antibiotic resistance enable S. aureus strains to produce a broad range of diseases. Thus, consumption of creamy pastries increases the risk of infection with S. aureus and it is a serious warning to the health system.

Designing a novel ELISA method based on CagA, NapA recombinant antigens to increase sensitivity and specificity of Helicobacter pylori whole cell antigen detection

AIM

In this research, we designed a direct Enzyme Linked Immunoassay method to detect Helicobacter pylori antigens in stool specimens.

BACKGROUND

Helicobacter pylori infection as the worldwide problem is related to many gastrointestinal disorders such as gastritis, gastric cancer, non-ulcer disease, peptic ulcer disease and duodenal ulcer.

METHODS

We produced and purified recombinant CagA and NapA antigens in Escherichia coli and extracted their antibodies from a panel of positive sera specimens. We designed a novel enzyme linked immunoassay direct method in combination with the whole cell for the qualitative and quantitative detection of Helicobacter pylori antigens in human stool. Assay performance was evaluated by histopathology staining and urease activity.

RESULTS

The sensitivity and specificity of assay was determined as 91.7 [95% confidence interval: 89.3-95.6%] and 93.1% [95% CI: 91.2-96.4%], respectively. Novel ELISA exhibits enhanced sensitivity and specificity of Helicobacter pylori detection in comparison with another commercially available kit.

CONCLUSION

Combination of the recombinant antigens and whole cell of Helicobacter pylori in immunoassay designing is a new approach about early diagnosis, treatment and fallowing up of the Helicobacter pylori infected patients, especially in peptic cancer cases.

Prevalence of the Most Common Virulence-Associated Genes among Brucella Melitensis Isolates from Human Blood Cultures in Hamadan Province, West of Iran

Brucellosis is a widespread zoonotic disease causing considerable economic and public health problems. Despite animal vaccination, brucellosis remains endemic in some areas such as Iran, especially in the western Iranian province of Hamadan. We sought to detect some of the most common virulence-associated genes in Brucella isolated from human blood cultures to determine the prevalence of some virulence genes among Brucella isolates. Fifty-seven isolates were studied from patients with a clinical diagnosis of brucellosis who referred to the Infectious Diseases Ward of Sina Hospital in Hamadan Province, Iran, between April 2013 and July 2014. Blood samples were collected for the diagnosis of brucellosis using the BACTEC blood culture system. All of these isolates were confirmed by the bcsp31 Brucella-specific gene. We detected 11 virulence-associated genes of Brucella, namely cβg, virB, znuA, ure, bvfA, omp25, omp31, wbkA, mviN, manA, and manB, which are important for the pathogenesis of this bacterium in the intracellular environment by multiplex PCR. Totally, 149 patients with a clinical diagnosis of brucellosis were enrolled in this study. Fifty-seven (38.3%) patients had positive blood cultures. On biochemical and molecular testing, all of the isolates were Brucella melitensis. Ten of the virulence genes were detected among all of the 57 isolates, but the bvf gene was detected in 53 (93%) isolates. The high prevalence of virulence-associated genes among the Brucella isolates detected in Hamadan Province, Iran, underscores the pathogenicity of this bacterium in this region.