Colorimetric bacteria sensing of Pseudomonas aeruginosa using gold nanoparticle probes.

BACKGROUND: Due to the advantages of molecular methods over biochemical methods, the use of molecular methods for diagnosing nosocomial infections such as Pseudomonas can be an appropriate and rapid way to choose the right diagnosis and treatment of infection and prevent further complications caused by the infection. The present article provides a description of the development of a nanoparticle-based detection technique for sensitive and specific deoxyribonucleic acid-based diagnostic of Pseudomonas aeruginosa. Specific thiolated oligonucleotide probes for one of the hypervariable regions of the 16S rDNA gene were designed and applied for colorimetric detection of the bacteria. RESULTS: The results of gold nanoprobe-nucleic sequence amplification indicated the probe attached to gold nanoparticles in the presence of the target deoxyribonucleic acid. It caused aggregation of gold nanoparticles in the form of connected networks resulting in color change and indicating the presence of the target molecule in the sample, which could be observed by the naked eye. In addition, the wavelength of gold nanoparticles changed from 524 to 558 nm. Multiplex polymerase chain reactions were performed using four specific genes of Pseudomonas aeruginosa (oprL, oprI, toxA, and 16S rDNA). The sensitivity and specificity of the two techniques were assessed. According to the observations, the specificity of both techniques was 100%, and the sensitivity was 0.5 ng/µL and 0.01 ng/µL of genomic deoxyribonucleic acid for multiplex polymerase chain reaction and colorimetric assay, respectively. CONCLUSIONS: The sensitivity of colorimetric detection was about 50 times higher than the polymerase chain reaction using the 16SrDNA gene. The results of our study proved to be highly specific with potential use for early detection of Pseudomonas aeruginosa.

Matrixyl Patch vs Matrixyl Cream: A Comparative In Vivo Investigation of Matrixyl (MTI) Effect on Wound Healing.

Wound healing is one of the most complex biological processes. Studies show that Matrixyl (MTI), known as a cosmetic peptide, can lead to a faster healing process. The contribution of MTI to collagen formation during wound healing also depends on its mode of delivery and its release over time. Here, we investigate two modes of MTI-delivery system, the influence of MTI patch for wound healing application in comparison with MTI cream. In this study, animals were randomly divided into seven groups and studied for 21 days: patches containing two different concentrations of MTI (P-MTI-0.1 mg and P-MTI-1 mg), a cream containing MTI (C-MTI-1 mg), a patch (P-MTI-0), a cream with no MTI (C-MTI-0), a positive control (Comfeel), and a negative control (sham) group. To study the wound healing process, the change in collagen density, angiogenesis, epitheliogenesis, histopathology, immunohistochemical analysis, and wound area through imaging was monitored and measured. The macroscopic results showed that wound healing was improved from 63.5 up to 81.81% in treatment groups compared to that in the negative control group (P < 0.05 and P < 0.001). In addition, C-MTI-1 and P-MTI-1 had a larger impact on wound healing compared to that in the positive control group (Comfeel, P < 0.05). In hematoxylin and eosin (H&E) staining analysis, the rejuvenation of skin appendage was visible in both groups of cream and patches with MTI. According to the obtained results, the re-epithelialization had a higher range for the patch with MTI in comparison with cream containing MTI and positive control.

The Effect of miR-145-5p, DANCR and NRAS Expression Levels on the Survival Rate of Colorectal Cancer Patients.

BACKGROUND: The prevalence of colorectal cancer (CRC) has been increasing in the world. There are different factors for colorectal cancer, and changes in the levels of gene expression such as miR-145-5p, DANCR and NRAS can be one of the factors. METHODS: The case-control study was performed on 40 CRC specimens and 40 adjacent healthy tissues. Fresh tumor and tumor-free adjacent tissue samples were obtained from patients who underwent the surgical operation as a conventional treatment procedure. After tumor resection, the specimens were immediately frozen in liquid nitrogen and stored at -80°C until further investigation. Cox regression was used to get the hazard ratios. RESULTS: The mean ± SD age of the patients was 62.45± 12.89 years. Of these, 62.5% were males. The risk of death from CRC in patients with low miR-145-5p levels is about 10 times higher than the high expression levels (HR = 10.759, P = 0.009). High expression levels of NRAS can increase the risk of CRC death up to 4 times (HR = 4.12, P = 0.045). The study did not show a relationship between DANCR expression levels and death risk from CRC (HR = 1.582, P = 0.439). CONCLUSION: These expression levels revealed that miRNA-145-5p and NRAS can be utilized as diagnostic biomarkers in colorectal cancer death. This may also introduce the microRNAs as colorectal cancer therapeutic targets.

Assessment of lncRNA DANCR, miR-145-5p and NRAS axis as biomarkers for the diagnosis of colorectal cancer.

Recent evidence reveals that miRNA sponges neutralize miRNAs activity by binding to miRNAs and sequester them from their relevant targets to regulate expression. The detailed mechanisms of sponge RNAs in colorectal cancer remain to be exactly determined. In this study DANCR, miR-145-5p, NRAS axis was evaluated and the diagnostic value of these targets was assessed in colorectal cancer patients. A case-control study was carried out on 40 samples of tumor tissues and 40 adjacent tissues. Total RNA was extracted, and then, the expression level of DANCR, miR-145-5p and NRAS was evaluated using qRT-PCR. In addition, the sensitivity and specificity of these markers were evaluated by receiver operating characteristic (ROC) curve analysis. Our results revealed that the expression level of DANCR was significantly upregulated in colorectal cancer tissues (p < 0.001). It was demonstrated that DANCR could regulate NRAS expression by sponging miR-145-5 in colorectal cancer patients. Furthermore, the mean expression of miR-145-5p (p < 0.001) and NRAS (p < 0.001) was significantly different between tumor and normal tissue. A significant correlation was observed between DANCR and miR-145-5p (p = 0.001), and also between miR-145-5p and NRAS (p < 0.001). Sensitivity and specificity value for DANCR, miR-145-5p and NRAS were (0.875 and 0.725), (0.875 and 0.745), and (0.877 and 0.694), respectively. According to the values of sensitivities and specificity of DANCR, miR-145-5p and NRAS, confirmed with ROC curve analysis, these biomarkers may be useful in the screening and differentiating between tumor and control sample in colorectal neoplasm.