Development of an HPV Genotype Detection Platform Based on Aggregation-Induced Emission (AIE) and Flow-Through Hybridization Technologies.

Genetic mutations can cause life-threatening diseases such as cancers and sickle cell anemia. Gene detection is thus of importance for disease-risk prediction or early diagnosis and treatment. Apart from genetic defects, gene detection techniques can also be applied to gene-related diseases with high risk to human health such as human papillomavirus (HPV) infection. HPV infection has been strongly linked to cervical cancer. To achieve a high-throughput HPV gene detection platform, the flow-through hybridization system appears to be one of the commercialized diagnostic techniques for this purpose. The flow-through hybridization technique is based on a vacuum-guided flow of DNA fragments which is continuously directed toward the oligoprobes that are immobilized on the testing membrane. However, the conventional colorimetric method and signal read-out approach suffers a problem of low sensitivity. On the contrary, fluorescence approaches allow more sensitive detection and broad sensing ranges. In this work, a fluorescent dye HCAP, which possesses aggregation-induced emission (AIE) properties and is responsive to alkaline phosphatase, was developed and applied to the flow-through hybridization platform to achieve HPV genome diagnosis of clinical samples. Also, an automatic membrane reader was constructed based on the AIE-based diagnosis platform which can identify the diagnostic result of patient DNA with a total concordance rate of 100% in the clinical trial.

Distribution characteristics of different human papillomavirus genotypes in women in Wuhan, China.

BACKGROUND: Human papillomaviruses (HPVs) are strongly associated with the development of cervical carcinoma, and the distribution of HPV genotypes varies regionally. METHODS: To investigate the distribution characteristics of different genotypes of HPV infection in women in Wuhan, China, a total of 13 775 patients were enrolled over 2 years. RESULTS: Of these, 2436 patients were infected with HPVs, and the total infection rate was 17.68%. The infection rate of high-risk HPV (HR-HPV) was significantly higher (13.96%) than that of single low-risk HPV (LR-HPV; 3.72%). Among the HR-HPV infections, the most common genotype was HPV 52 with an infection rate of 4.23%, followed by HPVs 16, 58, 39, and 51. The most common LR-HPV genotype was HPV 81, followed by HPVs 6, 11, and 44. Patients under the age of 25 years were found to have the highest HPV infection rate (P < .05). After the age range of 51-55 years, a downward trend in total HPVs and HR-HPVs was observed. The HPV infection rate for a single genotype was higher than that for multiple HPVs (P < .01), and the detection rates in summer and winter were significantly higher than those in spring and autumn. CONCLUSIONS: The results demonstrate that the distribution characteristics of various HPV genotype infections are associated with region and age and may be related to season. These data could be the basis for further epidemiological analysis into the control and prevention of HPV infection in this region.

Analysis of epidemiological trends in human papillomavirus infection among gynaecological outpatients in Hangzhou, China, 2011-2015.

BACKGROUND: HPV infection is the major pathogenic factor underlying cervical cancer and precancerous lesions. The cervical HPV infection rates in gynaecological outpatients from Hangzhou, China, were studied in the period from January 2011 to December 2015. METHODS: Exfoliated cervical cells were harvested from gynaecological outpatients in Hangzhou from January 2011 to December 2015. Twenty-one HPV subtypes were detected using flow-through hybridization. The HPV infection rates in various disease groups were compared using the Chi-square test. The infection rates of different HPV subtypes in different calendar years and in different age groups were analysed using the linear-by-linear association test and gamma value. RESULTS: A total of 43,804 patients were recruited, of whom 9752 (22.3%) were infected with HPV. The top five among the 21 HPV subtypes detected in terms of infection rates were HPV-16, -52, -58, -53 and -18. No significant differences (linear-by-linear association test) were found in the HPV infection rates when compared over the studied years (P > 0.05). However, the 15-24-year-old age group showed the highest HPV infection rate, and significant differences (linear-by-linear association test) were detected among the different age groups (P < 0.05). The HPV infection rates exhibited an upward trend in the 15-24-year-old and >24-34-year-old groups over the past five years. There were significant differences in the HPV infection rates among the disease groups (P < 0.05). CONCLUSIONS: HPV-16, -52 and -58 were the major HPV infection subtypes in Hangzhou, China. The 15-24-year-old age group had a relatively high HPV infection rate with an upward trend over the past five years and thus represented a population susceptible to HPV infection.

Prevalence of Chlamydia trachomatis, Ureaplasma urealyticum, and Neisseria gonorrhoeae in Asymptomatic Women from Urban-Peripheral and Rural Populations of Cuenca, Ecuador.

BACKGROUND: Sexually transmitted diseases (STDs) are a serious public health issue due to their high prevalence and a substantial percentage of women being asymptomatic. The present study aimed to determine the prevalence of three STD-causative pathogens in asymptomatic women from Southern Ecuador, with the ultimate purpose of updating the epidemiological data and obtaining a timely diagnosis, which can prevent further complications. METHODS: This cross-sectional study included 102 asymptomatic women from Cuenca, Ecuador, who underwent a cervical cytology examination. They met all the inclusion criteria and signed the consent form. Nucleic acids were extracted from each sample, and PCR and flow-through hybridization were performed to detect the pathogens responsible for three STDs. Descriptive and inferential statistics were used to define and describe the study population, obtain the frequency data, and measure central tendencies to determine possible associations among the variables. RESULTS: We found that 49.02% of the participants were infected with at least one of the three microorganisms, with 48.04% and 2.94% carrying Ureaplasma urealyticum (UU) and Chlamydia trachomatis (CT), respectively. Neisseria gonorrhoeae (NG) infection was not observed. Among the participants, 1.96% presented co-infections with CT and UU. Approximately half of the participants presented with asymptomatic infections caused by at least one microorganism. CONCLUSIONS: This study demonstrates the importance of conducting regular STD screening programs for high-risk asymptomatic women.

Analytical validation of viral CNS Flow Chip kit for detection of acute meningitis and encephalitis.

A new molecular assay (Viral CNS Flow Chip kit, Master Diagnóstica, Spain) has been developed for the detection of eight viruses causing acute meningitis and encephalitis, i.e. herpes simplex viruses 1-2, varicella zoster virus, human enterovirus, human parechovirus, Toscana virus, human cytomegalovirus and Epstein Barr virus. The new assay is a multiplex one-step RT-PCR followed by automatic flow-through hybridization, colorimetric detection and image analysis. The limit of detection was 50 copies/reaction, and 10 copies/reaction for human enterovirus and the other seven viruses, respectively. The analytical validation was performed with nucleic acids extracted from 268 cerebrospinal fluid samples and the results were compared with routine molecular assays. An excellent coefficient of agreement was observed between V-CNS and routine assays [kappa index: 0.948 (95%CI: 0.928-0.968)]. The overall sensitivity and specificity was 95.9% (95%CI: 91.2-98.3%) and 99.9% (95%CI: 99.6-100%), respectively. Viral CNS Flow Chip kit is an efficient multiplex platform for the detection of the main viruses involved in acute meningitis and encephalitis. The inclusion of a TOSV genome target may improve the laboratory diagnosis of viral neurological infections in endemic areas.

Rapid identification of Candida spp. frequently involved in invasive mycoses by using flow-through hybridization and Gene Chip (FHGC) technology.

The incidence of invasive fungal infections in immunocompromised patients has increased in recent decades. Rapid and accurate identification of these pathogenic fungi is crucial for initiating a timely, safe, and effective antifungal therapy. Here we developed a microarray based on flow-through hybridization gene chip technology. The microarray was tested for its specificity using a panel of reference and blinded clinical isolates. The results proved that this microarray was highly discriminative, leading to the unequivocal identification of each species, including Candida famata and the highly related species Candida parapsilosis, Candida orthopsilosis, and Candida metapsilosis. This new system represents a reliable method that is of potential use in clinical laboratories for the simultaneous detection and identification of the most common pathogenic fungi.

Distribution of 37 human papillomavirus types in parotid gland tumor tissues.

Human papillomavirus (HPV) infection has been shown to be associated with human tumorigenesis. The aim of the present study was to demonstrate the association between HPV infection and parotid gland tumors. Paraffin-embedded tissue sections from 59 cases of parotid gland tumors and 20 normal oral mucosa were subjected to DNA extraction and flow-through hybridization and gene chip technology to detect infection of 37 HPV types. The HPV-positive rate was 57.6% in parotid gland tumor paraffin-embedded tissue specimens, whereas, the normal control group was negative for HPV. The HPV-positive rate was 59.6% in parotid gland benign tumor tissues and 42.9% in parotid malignant tissues. HPV infection in parotid gland tumors was dominated by the high-risk subtypes (80.7%), which mainly consisted of HPV 16, 18 and 52 (61.4%). In addition, parotid gland tumor tissues were found to be infected by multiple or single types of HPV, but were predominantly infected by mixed HPV types. In this study, we found that the occurrence of parotid gland tumor is correlated with HPV infection.

Comparison of the DiagCor GenoFlow Human Papillomavirus Array Test and Roche Linear Array HPV Genotyping Test.

Persistent infection of high-risk (HR) human papillomavirus (HPV) infection has been widely associated with cervical cancer. Monitoring HPV infection is therefore an important step against cervical cancer development. The DiagCor GenoFlow Human Papillomavirus Array Test (GenoFlow) is a novel HPV test based on PCR and "Flow-through" hybridization that can identify 33 HPV subtypes in 3 hours. In the present study, the GenoFlow Test was evaluated by comparing the genotyping results of 100 samples with Roche Linear Array HPV Genotyping Test (LA). The tests showed good agreement in detection of HPV-positive samples (concordance rate=95%, Cohen's Kappa=0.896), with good agreement in detection of HR HPVs (Cohen's Kappa=0.876). The GenoFlow Test showed high sensitivity (95%), high specificity (95%), low false positive rate (3.33%) and low false negative rate (7.50%). In conclusion, the novel GenoFlow Test showed comparable clinical performance to LA test, and offers advantages of reduction in turnaround time and manpower.