The potential of circulating cell free RNA as a biomarker in cancer

Introduction: It is now clear that circulating cell-free ribonucleic acids (ccfRNAs), including messenger RNA (mRNA) and miRNA, are potential cancer biomarkers. As ccfmiRNA is relatively more stable than ccfmRNA, research should concentrate on developing novel methods to preserve the stability of ccfmRNA and standardization of the protocol which includes extraction, detection, and multicenter validation.

Areas covered: This literature review concentrates on the potential of ccfRNA being used as a biomarker in cancer, with special focus on mRNAs and microRNAs (miRNAs).

Expert opinion: With the advancement of high-throughput technologies such as RNA sequencing, a panel of biomarkers will be used for the diagnosis, prognosis and therapeutic monitoring of cancer patients. In order to achieve this important target, bioinformatics education to pathologists, scientists, and technologists in molecular diagnostic laboratories is essential. Moreover, the panel of these new ccfRNAs biomarkers has to obtain approval or clearance from an authority such as the US Food and Drug Administration (FDA), and the standard of utilizing these new protocols has to be recognized via accreditation exercise. Therefore, there is still a long way to go before an extensively use of ccfRNA biomarkers in cancer patients can be realized.     

Tonsillar Syphilis: an Unusual Site of Infection Detected by Treponema pallidum PCR

With the reemergence of syphilis, it is important that both clinical and public health practitioners recognize the various clinical manifestations of this disease (formerly known as “the great imitator”) and become familiar with the newer diagnostic tests. Here we report the first case of tonsillar syphilis diagnosed by PCR.     

Occurrence and distribution of antibiotics in surface water

Ecotoxicology - The concentrations, distribution, and ecological risks of 24 typical antibiotics in Hong Kong rivers and seawater were investigated using high-performance liquid chromatography...     

The Amsterdam Sexual Abuse Case: What Scars did it Leave? Long-Term Course of Psychological Problems for Children Who have been Sexually Abused at a Very Young Age,and their Parents

Child Psychiatry & Human Development - Longitudinal research of CSA in infancy and early childhood is scarce. The current study examined the long-term course of psychological outcomes (PTSD,...     

Identification of cultivable microorganisms from primary endodontic infections with exposed and unexposed pulp space

This study was aimed at comparing the cultivable microorganisms in canals with periapical radiolucencies with exposed and unexposed pulp space. Microbiological samples were taken and analyzed from 45 canals with exposed pulp space, and 43 canals with unexposed pulp space. The canal contents were analyzed by aerobic/anaerobic culture, and conventional identification techniques. There were 211 isolates of bacteria belonging to 28 genera and 55 species recovered from exposed canals. In the unexposed group, 185 isolates of bacteria were recovered, of which 54 species of 28 genera were identified. Among the four most common genera, Prevotella was significantly more common in the exposed group (51/211 in the exposed group versus 30/185 in the unexposed group) (p = 0.049), while there were no differences in prevalence of Actinomyces, Peptostreptococcus, and Campylobacter between two groups of canals. In addition, Fusobacterium nucleatum and Propionibacterium acne were significantly more common in the unexposed canals (p = 0.047 and p = 0.0051, respectively). Similarity in bacterial species in these two groups suggests that pulp space exposure may not be a significant factor in determining the type of bacteria present in infected canals.     

Heterogeneity in antifungal susceptibility of clones of Candida albicans isolated on single and sequential visits from a HIV-infected southern Chinese cohort

The increased frequency and severity of candidal infections in human immunodeficiency virus (HIV)-infected individuals has prompted the wide use of antifungals, such as amphotericin B, ketoconazole, and fluconazole, resulting in the emergence of drug-resistant strains of Candida albicans. To study this phenomenon in an ethnic Chinese cohort, we isolated multiple colonies of Candida from the oral cavities of 16 HIV-infected patients on single and subsequent sequential visits over a period of 12 months. Ten of the 16 patients had sporadic episodes of oropharyngeal candidiasis (Group A), while the remainder were asymptomatic with respect to this condition (Group B). Oral rinses were collected and immediately processed in the laboratory for the isolation of C. albicans in a standard manner. A total of 433 C. albicans isolates were tested for their susceptibility to amphotericin B, ketoconazole and fluconazole by an agar diffusion method using the commercially available E-test. All tested isolates demonstrated variable susceptibility to amphotericin B, ketoconazole and fluconazole. The minimum inhibitory concentration (MIC) of the isolates for amphotericin B, ketoconazole and fluconazole ranged from <0.002-1.5 microg/ml, <0.002-4.0 microg/ml and <0.016-32 microg/ml, respectively. Sequential isolates of a few patients demonstrated variable susceptibility to all the antifungals, and no discernible MIC pattern emerged either in group A or B over time. Interestingly, significant variation in antifungal susceptibility was also noted in isolates obtained from the same patient on a single visit. Sequential yeast isolates in 9 of 16 patients (56%) demonstrated significant differences in MIC within and between visits for both amphotericin B and ketoconazole, while a lower percentage--44%(7/16)--exhibited this trait for fluconazole. Our study demonstrates the diversity in antifungal susceptibility in either commensal or "infective" oral strains of C. albicans in HIV disease, and shows the need for vigilance for the emergence of resistant strains, and for frequent antifungal susceptibility studies.     

Dental caries and chemical warfare within the mouth

To date, it appears that the dentists' war against dental caries has no end in sight due to the fact that dentists lack any genuine offensive firepower. Make no mistake, the defense has drastically improved as dentists have shifted the focus more toward the preventive aspects of dental care. But defense by itself cannot defeat the enemy; at best, it can maintain the status quo. In order to defeat the enemy, one must study and understand the enemy, to know its strengths and weaknesses, and to strike at those points of vulnerability. The aim of this research is to identify and characterize genes that are responsible for observed virulence factors in Streptococcus mutans, which is the primary pathogen involved in the development of dental caries. Once there is a more defined understanding of the many virulence factors of S. mutans, there will be a much more valuable insight into its role in the ecology of the oral cavity. Eventually, this knowledge could enable dentists to convert the bacterial "weaponry" into its own arsenal, which could then be innovatively employed as preventive, diagnostic, and therapeutic agents to treat oral bacterial-related diseases.     

Comparison of cephalometric analysis using a non-radiographic sonic digitizer (DigiGraph Workstation) with conventional radiography

Cephalometric analysis conventionally requires radiographic exposure which may not be compatible with the growing concern over radiation hazards. Recently, the Dolphin Workstation Imaging System introduced to the dental profession a non-radiographic system, called the DigiGraph Workstation which may be an alternative to cephalometric radiography. The aims of this study were to compare the validity and reproducibility of cephalometric measurements obtained from the DigiGraph Workstation with conventional cephalometric radiographs. The sample consisted of 30 human dry skulls. Two replicated sets of lateral cephalograms were obtained with steel ball markers placed at the majority of the cephalometric landmarks. Duplicate tracings prepared from each radiograph were digitized to obtain cephalometric measurements using the computer software, Dentofacial Planner. For the DigiGraph Workstation, double sonic digitizations were repeated twice for each skull, on two occasions. Fifteen angular and one linear measurements were obtained from both methods and these findings compared using ANOVA, paired t-tests and F-tests. All, except one, cephalometric measurement showed significant differences between the two methods (P < 0.0001). The DigiGraph Workstation consistently produced higher values in 11 measurements (mean differences +0.5 to +15.7 degrees or mm) and lower values in four measurements (mean differences -0.2 to -3.5 degrees). The standard deviations of the differences between readings of both methods were large (0.4-5.8 degrees or mm). The reproducibility of the DigiGraph Workstation measurements was lower than that of the radiographic measurements. The method error of the DigiGraph Workstation ranged from 7 to 70 per cent, while that of radiographic tracings was less than 2 per cent. It was concluded that measurements obtained with the DigiGraph Workstation should be interpreted with caution.     

Antifungal susceptibility of <Emphasis Type="Italic">Candida albicans</Emphasis> biofilms on titanium discs with different surface roughness

Although it is well known that fungal biofilms have increased resistance to antimicrobial agents, limited information is available on the formation of candidal biofilms on implant surfaces with different surface roughness and their resistance to conventional antifungal therapy. In the current study, the effect of increasing the surface roughness of titanium discs on the susceptibility of Candida albicans biofilms to amphotericin B was determined. Grade I commercially pure titanium discs were sandblasted with 99.6% aluminium oxide of different grit sizes, producing surface roughness of 0.90, 1.88 and 3.82 μm (Groups A, B and C), respectively (P < 0.001). The antifungal susceptibility of C. albicans biofilm grown on different Ti discs was determined using XTT assay. The 50% reduction in metabolic activity (50% RMA) of planktonic C. albicans (0.5 μg/mL) was much lower than those from Groups A, B and C (2, 16, 2 μg/mL, respectively), while the 50% RMA from Group B was three-fold higher than those from Groups A and C. In conclusion, difference in titanium surface roughness was associated with variations in the antifungal resistance of the candidal biofilm. Group C appeared to have an optimum surface roughness for biofilm resistance.